Review and revision of the Olivoidea (Neogastropoda) from the Paleocene and Eocene of the U.S. Gulf Coastal Plain

Abstract

Numerous species of “oliviform” gastropods have been recognized in the Paleogene of the U.S. Gulf Coastal Plain, many of which have previously been allied to the “Bullia group” in the family Nassariidae, and placed in a variety of poorly defined genera. We review these species, revise their generic and familial placement, and present a phylogenetic analysis. Of 19 species considered valid, all are assigned to Olivoidea, six to Olividae—one to Oliva, five to Agaronia—and the rest to Ancillariidae. The highly variable species Ancillaria altile Conrad is referred in the genus Ancillopsis and appears to have evolved anagenetically over an interval of perhaps 20 million years. Ancillaria tenera Conrad and Ancillaria scamba Conrad are placed in the new genus Palmoliva. Monoptygma Lea is demonstrated to belong to Ancillariidae, and to contain only a single species. Specimens assigned to Lisbonia expansa Palmer are split into adults assigned to Ancillopsis altilis and juveniles (together with several other species) in the long-lived species Anbullina elliptica (Whitfield). Coastal Plain ancillariids may have evolved from one or more species of the Cretaceous–Paleocene genus Eoancilla. We agree with previous authors who have suggested that the late Eocene species Oliva mississippiensis Conrad is the earliest known representative of this genus and the subfamily Oliviinae, perhaps derived from a species of Agaronia. The oldest Agaronia is lower Eocene (Ypresian).

UUID: http://zoobank.org/b7d9f79b-c68b-4385-aba3-bb07c6d6dc87

Introduction

Neogastropods known as “olive shells” and their relatives (Superfamily Olivoidea, sensu Kantor et al., 2017) have been common components in many shallow marine communities for much of the past 50 million years. They include the families Olividae Latreille, 1825 (including the subfamilies Olivinae Latreille, 1825, Olivellinae Troschel, 1869, and Agaroniinae Olsson, 1956), Pseudolividae de Gregorio, 1890, Ancillariidae Swainson, 1840, Bellolividae Kantor et al., 2017, and Benthobiidae Kantor et al., 2017 (Fig. 1). Olivoidea includes ~460 extant species (WoRMS, 2021). Ancillariidae, which is of particular interest in this paper, includes at least 100 extant species and subspecies (Kilburn, 1981).

Figure 1. Phylogenetic relationships among living families of olivoid gastropods (based on Kantor et al., 2017).

The earliest known members of Olivoidea appear to have been ancillariids, which may include the stem group of the larger clade (Riedel, 2000; Vermeij, 2001, p. 507). The oldest ancillariids date to no later than the Late Cretaceous (Maastrichtian) (Sohl, 1964, p. 247–248; Kilburn, 1981; Tracey et al., 1993, p. 152). Kilburn (1981, p. 356) suggested that, based on poorly preserved material from the Cretaceous of Burma, Ancilla (Sparellina) poenitens Vredenburg (1923, p. 251, pl. 14, figs 5a, b) “was either an Ancilla or an Ancillarina”. Voskuil et al. (2011) mentioned four other species of likely Cretaceous Ancillariidae: Tanimasanoria japonica (Kase, 1990), Upper Cretaceous (lower Maastrichtian), Azenotani Mudstone Member, near Osaka, Japan; Eoancilla acutula Stephenson, 1941, Upper Cretaceous (Maastrichtian), Owl Creek Formation, Mississippi and Kemp Clay, Texas; Tanimasanoria sp. (Basse, 1932), Upper Cretaceous, Manja, Madagascar; and Oliva vetusta Forbes, 1846, Arriyalur Group, Upper Cretaceous (Maastrichtian), Pondicherry, India. Garvie (2013, p. 61) indicated that a Lower Cretaceous (Albian) fauna from Texas described by McCall et al. (2008) contains “a species that appears to be an ancestral Ancilla,” potentially extending the history of the group still further.

Numerous ancillariid species have been reported from the Paleocene and Eocene of Europe. Schnetler and Nielsen (2018, pl. 7, fig. 2) reported Ancilla from the Selandian of Denmark, and other European Paleogene species are discussed by Lozouet (1992), Pacaud et al. (2013), and Pacaud (2014). Eocene species from New Zealand are discussed by Olson (1956), Michaux (1987, 1991), and Beu and Maxwell (1990). Kilburn (1981, p. 356) suggested that the “earliest-known true Ancilla is probably A. boettgeri Martin (1914, p. 133, pl. 2, fig. 67) of the upper Eocene Nanggoelan beds of Java.” The genus Ancillarina Bellardi, 1882 (Selandian–Bartonian; type species Ancilla canalifera Lamarck, 1803) is also present in these beds; it includes “Ancilla-like species with a similarly divided fasciolar band but a total lack of callus on the spire whorls and sutures” (Kilburn, 1981, p. 356).

Numerous species of “oliviform” gastropods (sensu Kantor, 1991) have been recognized in the Paleogene of the U.S. Gulf Coastal Plain over almost 200 years, many of which previously have been allied to the “Bullia group” in the family Nassariidae, and placed in a variety of poorly defined genera. Previous work (Allmon, 1990) argued that these forms were not, in fact, related to Bullia s. s., but did not assign them to any other group. Here we review these forms and revise their generic and familial placement (Table 1). We place most of them in Olivoidea and present a phylogenetic analysis. Figure 2 shows the geological context and stratigraphic ranges of the species discussed here. We also discuss one species from the Eocene of France and the U.K., which we conclude is closely related to Coastal Plain species previously assigned to “Bullia.” The expanded calluses on the shells of some of the species discussed here make them almost spherical, and recently have been analyzed as examples of homoplasy (convergence and parallelism); the phylogenetic analysis presented here supports those conclusions (Pietsch et al., 2021).

Figure 2. Paleocene and Eocene stratigraphic units in the U.S. Gulf Coastal Plain (based on Garvie, 2013; Dockery and Thompson, 2016; Garvie et al., 2020) and stratigraphic ranges of the species discussed in this paper.

Table 1. Species of olivoid gastropods from the Paleocene and Eocene of the Gulf Coastal Plain (and U.K. and France) discussed in this paper.

Biology, shell morphology, and systematic characters

Living olivoids in general, and ancillariids in particular, are burrowing, sand-dwelling carnivores and scavengers (Kilburn, 1981; Cyrus et al., 2012; Kantor et al., 2017, p. 495; Robinson and Peters, 2018). The animal usually has a large foot with multiple folds that frequently extend far outside of, and may completely cover, the shell (Fig. 3) (Kilburn, 1981; Kantor et al., 2017, p. 519–522). Some species use the foot to swim or “surf” in turbulent water (Wilson, 1969).

Figure 3. Live ancillariid gastropod showing large foot covering the entire shell. Amalda australis collected from New Zealand (illustration from https://en.wikipedia.org/wiki/Amalda_australis#/media/File:Amalda_australis1.jpg).

The shell of Olivoidea (Fig. 4) is callused to different degrees, the functional significance and mode of formation of which remain poorly understood (Kantor et al., 2017, p. 519; Pietsch et al., 2021), and this has been described in numerous ways. Sometimes the callus is limited to the inner (parietal) wall of the aperture, but often it extends adapically, sometimes reaching or covering most or all of the spire, leaving only the protoconch and a part of the body whorl exposed. In many cases, the callus overlays or is associated with the sutures, which therefore may not be clearly visible externally. The callus may be uniform or consist of multiple layers, and these may vary throughout ontogeny. Kilburn (1977) and Kantor et al. (2017) have distinguished “primary” from “secondary” callus, with the primary usually forming a band around the anterior portion of each spire whorl, parallel to the suture, and the secondary callus located on the parietal wall of the aperture (ventral side of the shell), sometimes extending onto the spire, where it can cover primary callus. The primary callus, in this terminology, is therefore the secondary callus of earlier ontogenetic stages. Here we use a slightly different terminology, distinguishing spire callus from body whorl callus (Fig. 4.2), with the former forming a band on the anterior (abapical) part of each spire whorl, causing callusing associated with the sutures. For the body whorl callus, we distinguish the lateral extent (over the body whorl) from the posterior extent (extending posteriorly from the aperture toward the spire, sometimes covering the suture). Posterior body whorl callus will become spire callus as a subsequent whorl is added. Extensive posterior body whorl callus on subsequent whorls may then overlie spire callus of previous whorls. “Extreme parietal callus” (EPC) refers to the condition in which callus covers >50% of the ventral surface of the body whorl, which occurs on both olivoid and non-olivoid gastropods (Pietsch et al., 2021).

Figure 4. Shell morphological terminology used in this paper. (1) Modified from Kilburn (1981). (2) Terminology of the callus; lighter shading is spire callus (spc); darker shading is body whorl callus (bwc); bwc (lat) = body whorl callus, lateral; bwc (pos) = body whorl callus, posterior; (sc) = secondary callus; (pc) = primary callus; sc and pc are the terminology of Kantor et al. (2017); bwc (sc) means that the terms “body whorl callus” and “spire callus” are synonymous; spc (pc) means that the terms “spire callus” and “primary callus” are synonymous. See text for further discussion.

The anterior end of the olivoid shell bears a complex structure commonly referred to as the fasciole, formed by successive accretions of the anterior siphonal notch, which surrounds the anterior canal and its associated callus (Tursch and Greifeneder, 2001, p. 114–115; Kantor et al., 2017, p. 513–519). In all olivoids, the fasciole includes several more or less discrete zones or bands, which have been variously named in the literature (e.g., Kilburn, 1981; López et al., 1988; Tursch and Greifeneder, 2001; Pacaud et al., 2013). Here we use the terminology proposed by Kantor et al. (2017) (Fig. 4.1). The structure of the fasciole is important in discriminating olivoid shells from those of other neogastropods. For example, all representatives of the family Nassariidae lack the olivoid and anterior bands and show at least a slight terminal fold on the end of the fasciole (Allmon, 1990; Galindo et al., 2016).

Species of Ancillariidae can be distinguished conchologically from other olivoids by characters of callusing on the shell (Kantor et al., 2017, p. 535). Ancillariids are generally more strongly callused than other Olivoidea (but see Tursch and Greifeneder, 2001, p. 107–110), especially on the body whorl, and the suture between the spire and body whorl is usually overlaid with callus to varying degrees.

In this paper, we use the conception of fossil species advocated by Allmon (2016), which includes reference to morphological differences between extant species of a clade. The value of shell characters for recognition of species and genera in living olivoids remains unclear and is likely variable across the group. A number of modern olivid genera are distinguished only by non-shell characters. For example, some species of Oliva can be distinguished from species of Agaronia and Ancilla only by the radula (Zeigler and Porreca, 1969, p. 21). Kantor and Bouchet (2007, p. 27) described a new genus of Recent olivids, Calyptoliva, noting that it differs from the very similar Belloliva mainly “by the absence of a mantle filament and the presence of a mantle lobe.” Tursch and Greifeneder (2001) argued that morphospecies of Oliva are highly variable but frequently recognizable. Michaux (1987) showed that species of Amalda distinguished by electrophoresis also were distinguishable morphologically, but Kantor et al. (2016) found that several molecularly distinct species of Ancilla were morphologically cryptic. Thus, it is possible that morphospecies recognized here based solely on fossils include more than a single biological species.

Phylogenetic analysis

Methods

Our preliminary phylogenetic analysis included 19 Paleocene–Eocene species representing three genera of Olividae and seven genera of Ancillariidae. We also included the Recent species Agaronia testacea (Lamarck, 1811) and Oliva sericea (Röding, 1798) for comparison. We used type and figured material to code each species for the following discrete character suites: (1) suture; (2) callus; (3) bands (including the olivoid, anterior, subsutural, and body whorl bands); (4) columella and plications; (5) ornamentation and texture; and (6) shell shape. In instances where museum specimens were unavailable, taxa were coded using primary taxonomic figures and literature. Species were coded for 27 discrete characters (10 binary and 17 multistate) (Table 2) that were selected to capture morphological variation among the clades and are inferred to represent homologous structures among sampled taxa. Eoancilla was designated as the outgroup because the genus is a putative ancestor of the other ancillariids (Garvie, 2013).

Table 2. Characters scored for phylogenetic analysis (see Figure 4 for shell terminology).

A parsimony analysis was conducted in PAUP* v. 4.0a147 (Swofford, 2003) using a heuristic search with 10,000 random addition sequences. TBR (tree bisection reconnection) was used for the branch-swapping algorithm with no reconnection limit and collapsing all branches with a maximum branch length of zero. All characters were left unordered and equally weighted. Nexus files utilized are provided as Supplement 1. Values for consistency index (CI) and retention index (RI) were recorded for recovered trees, and bootstrap values and Bremer support were calculated using PAUP*.

Results

The parsimony analysis recovered 82 most parsimonious trees with tree lengths of 111 steps (CI 0.485, RI 0.541). Strict and semi-strict consensus of the most parsimonious trees resulted in a tree topology with poor resolution (Fig. 5.1). The 50% majority rule consensus tree (Fig. 5.2) gives better resolution and was plotted against the observed stratigraphic ranges of sampled genera to produce a time-scaled phylogeny (Fig. 20).

Figure 5. Phylogenetic relationships among the fossil species discussed in this paper. Numbers on branches are the number of trees with that arrangement. (1) Strict consensus of 82 equally parsimonious trees. (2) 50% majority-rule consensus of 82 equally parsimonious trees. Sister taxa are relatively well supported with four of the six pairs appearing in all of the most parsimonious trees, although support was lowest for the Palmoliva n. gen. pair. As the only representatives of their genera, M. alibamasiana and B. weisbordi support their genus’ distinction from the other genera (Agaronia, Oliva, Anbullina, Monoptygma, and Palmoliva n. gen.) in their larger clade. See text for further discussion.

Material

Repositories and institutional abbreviations

Academy of Natural Sciences of Drexel University, Philadelphia, PA, USA (ANSP); Alabama Museum of Natural History, Tuscaloosa, AL, USA (ALMNH); Bureau of Economic Geology, Austin, TX, USA (BEG; collections now referred to as NPL); Florida Geological Survey, Tallahassee, FL, USA (FGS; collection now at Florida Museum of Natural History, Gainesville); Field Museum, Chicago, IL, USA (FMNH); Geological Survey of Alabama (Type Cabinet), Tuscaloosa, AL, USA (GSA (GSATC)); Museum of Geosciences, Louisiana State University, Baton Rouge, LA, USA (LSU); Department of Invertebrate Paleontology, Museum of Comparative Zoology, Harvard University, Cambridge, MA, USA (MCZIP); Mississippi Geological Survey collection, Jackson, MS, USA (MGS); Muséum National d'Histoire Naturelle, collection de Paléontologie, Paris, France (MNHN); Paleontological Research Institution, Ithaca, NY, USA (PRI); Non-Vertebrate Paleontological Laboratory, University of Texas, Austin, TX, USA (NPL = NVPL of some previous authors); Texas Memorial Museum, Austin, TX, USA (TMM; collections now referred to as NPL); Université Claude Bernard, Lyon, France (UCBL); Florida Museum of Natural History, University of Florida, Gainesville, FL, USA (UF); National Museum of Natural History, Smithsonian Institution, Washington, DC, USA (USNM).

Systematic paleontology

In the species accounts below, morphological terminology follows Figure 4. Specimen measurements for all species are given in Table 3.

Table 3. Measurements for representative specimens.

Phylum Mollusca Linnaeus, 1758
Class Gastropoda Cuvier, 1797
Family Olividae Latreille, 1825
Subfamily Olivinae Latreille, 1825
Genus Oliva Bruguière, 1789

Type species

Voluta oliva Linnaeus, 1758; subsequent monotypy by Lamarck, 1799.

Remarks

Conchologically, the genus Oliva is distinguished by having a “[p]lication plate subdivided into parietal plate, shoe and belt. Filament channel well defined, eventually overlaid by primary spire callus on upper spire whorls, but free at least on last whorl” (Kantor et al., 2017, p. 526). Tursch and Griefender (2001) recognized 74 extant morphospecies.

Oliva mississippiensis Conrad, 1848
Figure 6.1, 6.2

1848a

Oliva mississippiensis Conrad, p. 289.

1848b

Oliva mississippiensis Conrad, p. 119, pl. 3, figs. 6, 38.

1865a

Lamprodoma Mississippiensis; Conrad, p. 22.

1866

Lamprodoma Mississippiensis; Conrad, p. 30.

1903

Oliva mississippiensis; Casey, p. 281.

1945

Oliva mississippiensis; Gardner, p. 216.

1947

Agaronia mississippiensis; Harris and Palmer, p. 410, pl. 63, figs. 17–19.

1966

Agaronia mississippiensis; Palmer and Brann, p. 487.

1977

Agaronia mississippiensis; Dockery, p. 79, pl. 11, fig. 3A, B.

1981

Strephonella mississippiensis; Drez, p. 105.

1984

Oliva (Strephonella) mississippiensis; MacNeil and Dockery, p. 157, pl. 33, figs. 17, 18, pl. 56, figs. 13, 14.

Figure 6. Oliva, Bulovia, and Agaronia. (1, 2) Oliva mississippiensis lectotype ANSP 13450; height 27.1 mm. (3, 4) Agaronia bombylis (Oliva bombylis lectotype ANSP 14627); height 22.3 mm. (5, 6) Bulovia weisbordi holotype PRI 3048; height 22.2 mm. (7–14) Agaronia alabamensis: (7, 8) Oliva alabamensis lectotype ANSP 14649; height 41 mm. (9, 10) Oliva greenoughi holotype ANSP 5916; height 42 mm. (11, 12) Oliva gracilis holotype ANSP 5914. (13, 14) Oliva dubia holotype ANSP 5920; height 39 mm. (15–17) Agaronia media: (15) lectotype GSA-I17375; height 7 mm. (16) hypotype MGS 2074; height 19.5 mm. (17) hypotype (Harris and Palmer, 1947) PRI 20009; height 9 mm. (18–21) Agaronia inglisia: (18, 19) holotype UF 108756; height 29.4 mm. (20) UF 5455; height 38 mm. (21) UF 66680 silicone cast of mold in limestone. Cast measures 40 × 50 mm.

Type material

Lectotype ANSP 13450; hypotypes (Harris and Palmer, 1947, pl. 63) PRI 20010, 20011, 20012.

Occurrence

Louisiana: upper Eocene (Bartonian–Priabonian), Moodys Branch and Yazoo formations (Loc. LA-GR-1); Mississippi: lower Oligocene (Rupelian), Mint Springs Formation (Loc. MS-WA-23).

Remarks

Drez (1981) and Petuch and Sargeant (1986, p. 10–11) identified this species as the earliest olivid; Drez placed it in the genus Strephonella, and Petuch and Sargeant in Oliva. MacNeil and Dockery (1984, p. 157) placed Strephonella as a subgenus of Oliva, and recognized a second similar species, O. (Strephonella) affluens Casey, 1903, in the Moodys Branch Formation. Both of these forms appear to be closer to Oliva than to Agaronia, due to their inflated body whorl, wide and complex plication plate bearing sharp plications, and presence of a parietal plate posterior of the plication plate (see Tursch and Greifeneder, 2001, p. 112). Given its similarity to Agaronia, it is possible that this species (and therefore the clade Olivinae) is derived from a species of that genus (see further discussion below).

Subfamily Agaroninae Olsson, 1956
Genus Agaronia Gray, 1839

Type species

Voluta hiatula Gmelin, 1791, by monotypy.

Remarks

Conchologically, the genus Agaronia is distinguished by having a “[p]lication plate not distinctly subdivided, with distinct spiral plicae. Olivoid groove present, shallow. Olivoid band differing or not in color from cloak of last whorl. Filament channel well defined, free on most spire whorls” (Kantor et al., 2017, p. 526). The shell is less glossy than in Oliva, with a taller, more acuminate spire and slightly flaring outer apertural lip. López et al. (1988, p. 296) suggested that the “count of lirae [on the inner lip of the aperture]” and the “height and shape of the spire” provide useful specific characters in Agaronia.

Agaronia was originally described by Gray (1839) as a subgenus of Olivancillaria, which was accepted by some later authors. It was elevated to a separate genus by Olsson (1931), and this has been more widely accepted. Agaronia is most often placed in a monotypic subfamily, Agaroniinae (Olsson, 1956; Ponder and Warén, 1988; Sterba, 2003; Kantor et al., 2017), although Bouchet and Rocroi (2005) and Cilia (2012) placed it in Olivinae. The majority of the ~20 described extant species occur on low-latitude coasts of west Africa, western Central America, and the eastern Indian Ocean (see López et al., 1988; Cilia, 2012). The oldest recognized species is Agaronia bombylis (Conrad, 1833) from the Lower Eocene (Ypresian) (see below).

We recognize four species of Agaronia in the Paleogene of the Coastal Plain and Florida: A. alabamensis (Conrad, 1833), A. bombylis (Conrad, 1833), A. media (Meyer, 1885), and A. inglisia (Palmer in Richards and Palmer, 1953). We follow Garvie (2021) in placing the species A. mediavia (Harris, 1896) in the genus Eoancilla Stephenson, 1941.

Our phylogenetic analysis (see below) indicates that Agaronia is paraphyletic and includes the ancestry of Oliva mississippiensis. Since a thorough phylogenetic analysis of all fossil and extant Agaronia is beyond the scope of this paper, we use the name Agaronia sensu lato to include all Coastal Plain Paleogene species.

Agaronia alabamensis (Conrad, 1833)
Figure 6.7–6.14

non 1829

Oliva gracilis; Broderip and Sowerby, p. 379.

1833

Oliva alabamensis Conrad, p. 32.

1833

Oliva Greenoughi Lea, p. 183, pl. 6, fig. 197.

1833

Oliva dubia Lea, p. 183, pl. 6, fig. 198.

1833

Oliva Phillipsii Lea, p. 184, pl. 6, fig. 199.

1833

Oliva gracilis Lea, p. 182 [in part], pl. 6, fig. 196.

1834b

Oliva Phillipsii; Conrad, p. 5.

1834b

Oliva alabamensis; Conrad, p. 5.

1835

Oliva alabamensis; Conrad, p. 41, pl. 16, fig. 3.

non 1835

Ancillaria dubia; Deshayes, p. 734.

non 1835

Oliva nitidula Deshayes, p. 741.

1835

Oliva alabamiensis [sic]; Duclos, pl. 18, figs. 13, 14.

1844

Oliva alabamiensis [sic]; Duclos, p. 11, pl. 20, figs. 13, 14.

1846

Oliva alabamensis; Conrad, p. 220.

1849

Oliva alabamensis; Lea, p. 103.

1849

Oliva Greenoughi; Lea, p. 103.

1849

Oliva dubia; Lea, p. 103.

1849

Oliva Phillipsii; Lea, p. 103.

1849

Oliva gracilis; Lea, 1849, p. 103.

1850

Oliva Phillipsii; d'Orbigny, p. 351.

1850

Oliva alabamensis; d'Orbigny, p. 351.

1858

Oliva alabamensis; Tuomey, p. 266.

1865a

Lamprodoma alabamiensis [sic]; Conrad, p. 22.

1865a

Lamprodoma gracilis; Conrad, p. 22.

1865a

Lamprodoma Phillipsii; Conrad, p. 22.

1866

Lamprodoma alabamiensis [sic]; Conrad, p. 17.

1866

Lamprodoma gracilis; Conrad, p. 17.

1866

Lamprodoma Phillipsii; Conrad, p. 17.

1890

Oliva Phillipsii; de Gregorio, p. 53, pl. 3, fig. 66 [copied Lea, 1833].

1890

Oliva gracilis; de Gregorio, p. 52, pl. 3, fig. 50, 51 [copied Lea, 1833].

1890

Oliva nitidula; de Gregorio, p. 51, pl. 3, figs. 36–42.

1890

Oliva mitreola Lamarck; de Gregorio, p. 51, pl. 3, fig. 47, 48 [not Lamarck, 1803, p. 391].

1890

Oliva antelucana; de Gregorio, p. 54, pl. 3, figs. 58–61.

1890

Oliva pinaculica; de Gregorio, p. 54, pl. 3, figs. 63–65.

1891

Oliva gracilis; Heilprin, p. 397.

1893

Olivella alabamiensis [sic]; Cossmann, p. 40.

1893

Olivella Phillipsi; Cossmann, p. 40.

1895b

Oliva alabamensis; Harris, p. 3.

1899

Olivancillaria (Agaronia) alabamiensis [sic]; Cossmann, p. 51.

non 1899

Oliva parisiensis; Cossmann, p. 178.

1926a

Oliva alabamensis; Cooke, pl. 95, fig. 5.

1935

Olivancillaria (Agaronia) alabamiensis [sic]; Davies, p. 306.

1937

Agaronia alabamensis; Palmer, p. 431, pl. 68, figs. 14–16, 18–22, pl. 89, fig. 5.

non 1937

Oliva parnensis; Palmer, p. 431.

1944

Olivella (Agaronia) alabamensis; Shimer and Shrock, p. 511, pl. 210, fig. 13 [copied Conrad, 1935a].

1947

Agaronia alabamensis; Harris and Palmer, p. 408.

1960

Agaronia alabamensis; Brann and Kent, p. 29.

1960

Olivancillaria (Agaronia) alabamiensis [sic]; Glibert, p. 19.

1966

Agaronia alabamensis; Palmer and Brann, p. 484.

Type material

Lectotype + 8 specimens ANSP 14649; holotype Oliva greenoughi ANSP 5916; holotype Oliva dubia ANSP 5920; holotype Oliva phillipsii ANSP 5926; holotype Oliva gracilis ANSP 5914; hypotypes Agaronia alabamensis (Palmer, 1937) PRI 3288, 3289, 3290, 3291, 3292, 3293.

Occurrence

Alabama: middle Eocene (Lutetian–Bartonian), Lisbon Formation, Gosport Sand (Locs. AL-CL-1, AL-MO-2a, b); South Carolina: middle Eocene (Bartonian), McBean Formation (Loc. SC-OR-1); Texas, Louisiana, Mississippi: middle Eocene (Lutetian–Bartonian), Cook Mountain Formation (see Palmer, 1937, p. 434).

Revised description

Shell large. Protoconch of one and a half or two smooth whorls, and the sutures are indistinct, not channeled as on teleoconch whorls. Spire up to ~0.25 total height in adults, shorter in juveniles. Sutures channeled. Shell smooth. Callus extends only slightly laterally out of aperture over body whorl and posteriorly toward spire, creating narrow callus band, often of lighter color, above sutures. Aperture ~0.6 total height, narrowing posteriorly into a sharp channel and widening anteriorly to a broad channel. Olivoid band distinct and continuing on dorsal side, with sharp posterior margin. Another band often present posterior to olivoid band, consisting of smooth stripe or slight concavity on body whorl, bounded posteriorly by slight rounded ridge. Anterior band distinct, separated from olivoid band by faint line. Plication plate distinct, slightly inflated, bearing multiple plications, separated from anterior band by deep groove.

Other material examined

MCZIP 29246 (5 specimens); PRI 14142 (172 specimens); PRI 104503 (2 specimens); PRI 104693 (2 specimens).

Remarks

This species is one of the most common large gastropods in the upper middle Eocene Gosport Sand of Alabama (CoBabe and Allmon, 1994; Pietsch et al., 2016). Kelley and Swan (1988) noted that Agaronia alabamensis shows a single pigmented spiral band parallel to the suture. Gosport specimens are larger than those from other stratigraphic units (Haveles and Ivany, 2010).

Agaronia bombylis (Conrad, 1833)
Figure 6.3, 6.4

non 1829

Oliva gracilis; Broderip and Sowerby, p. 379 [fide Palmer and Brann, 1966, p. 486].

1833

Oliva bombylis Conrad, p. 32.

1833

Oliva constricta Lea, p. 182, pl. 6, fig. 195.

1833

Oliva gracilis; Lea, p. 182 (part).

1835

Oliva bombylis; Conrad, p. 42, pl. 16, fig. 4.

1835

Oliva bombylis; Duclos, pl. 18, figs. 7, 8.

1846

Oliva bombylis; Conrad, p. 220.

1849

Oliva bombylis; Lea, p. 103.

1849

Oliva constricta; Lea, p.103.

1850

Oliva bombylis; d'Orbigny, p. 351.

1865a

Lamprodoma bombylis; Conrad, p. 22.

1866

Lamprodoma bombylis; Conrad, p. 17.

1879

Oliva bombylis; Heilprin, p. 223.

non 1886

Oliva bombylis; Aldrich, p. 53 [fide Palmer and Brann, 1966, p. 485].

non 1886

Oliva gracilis; Aldrich, p. 56 [fide Palmer and Brann, 1966, p. 486].

1890

Oliva bombylis; de Gregorio, p. 52, pl. 3, fig. 49, [copied Conrad, 1835], fig. 52 [copied Oliva constricta Lea, 1833].

1893

Olivella bombylis; Cossmann, p. 40.

1895b

Oliva bombylis; Harris, p. 8.

1899

Olivella bombylis; Cossmann, p. 54.

1937

Agaronia bombylis; Palmer, p. 434, pl. 68, figs. 12, 13.

1960

Olivancillaria (Agaronia) bombylis; Glibert, p. 19.

1966

Agaronia bombylis; Palmer and Brann, p. 485.

Type material

Lectotype ANSP 14627; holotype Oliva constricta ANSP 5911; hypotypes (Palmer, 1937) PRI 3286, 3287.

Occurrence

Texas: middle Eocene (Ypresian–Bartonian), Weches Formation, Stone City Formation, Cook Mountain Formation (Locs. TX-BA-1); Alabama: middle Eocene (Lutetian–Bartonian), Upper Lisbon Formation, Gosport Sand (Locs. AL-MO-2a, AL-MO-5); South Carolina: middle Eocene (Bartonian), McBean Formation (Loc. SC-OR-1).

Revised description

Shell small and elongate. Protoconch of one and one-half or two whorls. Spire 0.2–0.25 total height. Sutures channeled. Callus extends only slightly laterally out of aperture over body whorl and posteriorly toward spire, creating wide callus band, usually of lighter color, above sutures. Shell smooth. Aperture 0.5–0.6 total height. Aperture narrow, pinching to sharp channel posteriorly and wider anteriorly. Olivoid band distinct, bounded posteriorly by a sharp line or groove. Anterior band distinct, bounded posteriorly by rounded ridge. Plication plate distinct with multiple plications. Columellar terminus pointed.

Other material examined

PRI 56684 (1 specimen), PRI 56028 (35 specimens).

Remarks

As noted by Palmer (1937, p. 434–435), juvenile A. alabamensis and A. bombylis may be confused with each other, but are distinguishable by overall shell shape, with A. bombylis being consistently more slender in its bodywhorl. In A. bombylis, the callus band above the suture is also relatively wider and more conspicuous. Agaronia bombylis does not attain the size or abundance of A. alabamensis. Kelley and Swan (1988) noted that Agaronia bombylis shows a single pigmented spiral band parallel to the suture. Palmer (1937, p. 435; Palmer and Brann, 1966, p. 486) stated that it occurs in the Weches and Stone City formations of Texas, but we have not been able to locate these specimens in the PRI collection. These reported occurrences are important because they considerably extend the stratigraphic range of the species downward (see Fig. 2).

Agaronia inglisia Palmer in Richards and Palmer, 1953
Figure 6.18–6.21

1953

Agaronia inglisia Palmer in Richards and Palmer, p. 31, pl. 6, figs. 5, 8, 13.

1966

Agaronia inglisia; Palmer and Brann, p. 486.

Type material

Holotype FGS I-7604 (UF 108756); paratypes FGS I-7605 (UF 108760), FGS I-7606 (UF 108764).

Occurrence

Florida: upper Eocene (Bartonian–Priabonian), Inglis Formation (Loc. FL-LE-1).

Revised description

Shell medium-sized. Protoconch bulbous, of ~1.5 whorls. Spire <0.2 total height. Sutures deeply grooved. Callus extends posteriorly from aperture about half-way to suture. Body whorl smooth, unsculptured. Aperture narrow, ~0.6 total height. Olivoid and anterior bands marked by strong grooves. Plication plate relatively wide.

Other material examined

UF 5396 (1 specimen), UF 5448 (2 specimens), UF 5455 (2 specimens), UF 6794 (2 specimens), UF 12753 (1 specimen), UF 19132 (2 specimens), UF 66680 (1 specimen), UF 106738 (1 specimen), UF 107439 (1 specimen).

Remarks

This is the only species of Agaronia known from the Eocene of Florida.

Agaronia media (Meyer, 1885)
Figure 6.15–6.17

1885

Oliva media Meyer, p. 465.

1926b

Olivella jacksonensis Cooke, p. 134, fig. 5.

1947

Agaronia jacksonensis; Harris and Palmer, pl. 63, fig. 10.

1947

Agaronia media; Harris and Palmer, p. 407, pl. 63, figs. 7, 9, 11–13.

1966

Agaronia media; Palmer and Brann, p. 486.

1977

Agaronia media; Dockery, p. 79, pl. 11, figs. 1A, B, 2A, B.

Type material

Syntypes and lectotype GSA-I17375 (includes “holotype” listed in Palmer and Brann, 1966, p. 486, as GSATC 78); hypotypes (Harris and Palmer, 1947) PRI 20009, (Dockery, 1977) MGS 2073, 2074.

Occurrence

Mississippi: upper Eocene (Bartonian–Priabonian), Moodys Branch Formation (Locs. MS-CL-2, MS-HI-3, MS-HI-4); Arkansas, Louisiana, Texas: (see Palmer and Brann, 1966, p. 486).

Revised description

Shell small. Protoconch spherical. Spire ~0.25 total height. Suture strongly channeled. Callus minimal. Shell smooth, shiny, unsculptured. Aperture narrow, ~0.5 total height. Olivoid and anterior bands well marked. Plication plate narrow.

Remarks

Meyer (1885) did not figure the species when he described it, nor did he designate a type specimen. According to Palmer (in Harris and Palmer, 1947, p. 408), the collection in the Alabama Museum of Natural History included eight specimens labeled as “types,” probably by Alabama State Paleontologist Winnie McGlamery. From among these, Palmer selected one as a lectotype. Unfortunately, this specimen was not kept separate and was recombined with 52 others in a single vial, all being given the number GSATC 78; they have since been given the new number GSA-I17375 (T.L. Harrell, personal communication, October 21, 2021). From these, one specimen was identified by T.L. Harrell as the most likely to have been Palmer's lectotype, and it is figured here (Fig. 6.15). Harris and Palmer (1947, p. 407) reported this species to be “very common” in the Moodys Branch Formation at Jackson, MS.

Genus Bulovia Palmer, 1937

Type species

Bulovia weisbordi Palmer, 1937, by original designation.

Remarks

The shell is very distinctive, which led Palmer to put it in a new monotypic genus. It resembles species of Agaronia in its strong olivoid and anterior bands, aperture shape, and strongly channeled suture, and we have been tempted to place it in Agaronia. In our phylogenetic analyses (Fig. 5), however, Bulovia weisbordi consistently falls outside of Agaronia because of the unique shape of the anterior end of the shell, especially the deep groove separating the plication plate and anterior band. Despite it being represented by a single specimen, we therefore retain it in Palmer's monotypic genus Bulovia.

Bulovia weisbordi Palmer, 1937
Figure 6.5, 6.6

1937

Bulovia weisbordi Palmer, p. 293, pl. 40, figs. 10, 11.

1943

Bulovia weisbordi; Wenz, p. 1226, fig. 3489 [copied Palmer, 1937, pl. 40, fig. 10].

1960

Bulovia weisbordi; Brann and Kent, p. 140.

1966

Bulovia weisbordi; Palmer and Brann, p. 546.

1982

Bullia (Bulovia) weisbordi; Cernohorsky, p. 17.

1990

Bulovia weisbordi; Allmon, p. 60, pl. 9, fig. 5.

Type material

Holotype PRI 3048.

Revised description

Shell small and slender. Protoconch unknown. Spire ~0.2 total height. Sutures are callused, with a prominent sutural band and the last suture deeply channeled. Callus extends posteriorly from aperture almost to suture, and laterally over more than half of body whorl. Growth lines have prominent relief on spire and body whorl beneath a prominent smooth subsutural band. Aperture wide, just over half total height, with a wide anterior canal. Olivoid and anterior bands very prominent. Plication plate narrow and smooth, separated from anterior band by a very deep groove, almost a pseudoumbilicus.

Occurrence

Texas: middle Eocene (Ypresian), Weches Formation (Loc. TX-BA-1).

Remarks

Bulovia weisbordi is known only from its holotype specimen, from the now-inaccessible Smithville outcrop of the Weches Formation in Texas.

Family Ancillariidae Swainson, 1840
(= Ancillinae Adams and Adams, 1853)

Diagnosis

(Kantor et al., 2017, p. 530) “Shell glossy or mat, lacking periostracum, fusiform to narrowly fusiform, with high last whorl, and medium broad-to-narrow aperture tapering adapically. Siphonal canal absent, anterior end of shell distinctly notched. Anterior shell end with well-defined anterior band, raised above the shell cloak and often strongly shagreened. Olivoid groove present (at least in some species) in all genera. Plication plate limited to columella, usually with spiral plicae. Primary spire callus well defined, covering most of, or even completely, the shell. Secondary spire callus from poorly defined to very strong. Suture always overlaid by the callus.”

Genus Ancillopsis Conrad, 1865

Type species

Ancillopsis altilis Conrad, 1865a, by subsequent designation (Cossmann, 1899, p. 45).

Diagnosis

Shell medium to very large. Spire in juveniles one-fourth or less of total height; spire in adults may be only a tiny point above the expanded callus, which may make shell subspherical. Aperture one-half to two-thirds total height. Sutures simple in juveniles, heavily callused on adults. Shell in juveniles lanceolate in overall shape; in adults shell is oval to almost circular and may be dorso-laterally flattened. Olivoid band and anterior bands pronounced. Plication plate narrow and simple and usually callused. Anterior end of columella a simple point.

Remarks

When he first introduced the name Ancillopsis, Conrad (1865a, p. 22) did not provide a description (he also erroneously gave the date of its introduction as 1864), but listed four species (altile, scamba, subglobosa, and tenera) (he had earlier [Conrad, 1832, 1834a] placed these in Ancillaria, but this name was already preoccupied by Ancillaria Lamarck, 1799). These species were allied with Nassariidae by Cossmann (1893), who placed them in the genus Buccinanops. Palmer (1937) agreed with this familial placement but moved them all into the nassariid genus Bullia. Gardner (1945, p. 199) rejected Palmer's judgement, suggesting that the “much smaller protoconch and the banding of the body by the change in direction of the growth lines are probably significant characters in separating Ancillopsis from Bullia.” Allmon (1990) similarly argued that Ancillopsis and associated forms were not closely related to Bullia, but did not assign them to another group. Pacaud and Cazes (2014) reiterated the case for an assignment of altilis and similar forms to Bullia. Dockery (1980) figured a small specimen with axial ribs on early whorls from the Cook Mountain Formation of Mississippi, referring it to “Bullia sp.”, which may belong to the species A. altilis.

Species assigned here to Ancillopsis have in common with other species of Ancillariidae the presence of olivoid and anterior bands, which are not present in Recent species of Bullia (Fig. 7). Furthermore, the form of the anterior end of the columella is different between Ancillopsis altilis and extant Bullia species (Fig. 7): in A. altilis, the end comes to an acute point, while in Bullia, it is terminated by a fold. For these reasons, altilis and related forms can be placed in the genus Ancillopsis in the family Ancillariidae.

Figure 7. Comparison of the anterior ends of the shell in three living species of Bullia and specimens of Ancillopsis, which have been placed by other authors in Bullia. The Bullia specimens (1–3) all show a terminal columellar fold (arrows), whereas the specimens of Ancillopsis (4, 5) do not. (1) Bullia vittata (Linnaeus, 1767), Sri Lanka, PRI 104508. (2) Bullia laevissima (Gmelin, 1791), South Africa, PRI 104509. (3) Bullia annulata (Lamarck, 1816), South Africa, PRI 104507. (4) Ancillopsis altilis, Gosport Sand, Alabama (Loc. AL-MO-2a), PRI 83941. (5) Ancillopsis patula, Eocene, Ducy, France (Loc. FR-1), PRI 83935. All scale bars = 1 cm.

Pacaud and Cazes (2014) reported preserved color patterns on specimens of the two species here included in this genus (A. altilis and A. patula).

Ancillopsis altilis (Conrad, 1832)
 Figures 8.1–8.21, 9.1, 9.10, 9.13, 9.14, 9.16, 9.17, 10

1832

Ancillaria altile Conrad, p. 24, pl. 10, fig. 2.

1832

Ancillaria subglobosa Conrad, p. 25, pl. 10, fig. 3.

1833

Anolax gigantea Lea, p. 180, pl. 6, fig. 193.

1849

Ancillaria subglobosa; Lea, p. 96.

1850

Ancyllaria subglobosa; d'Orbigny, p. 352.

1862

Tritia altilis; Conrad, p. 562.

1865a

Ancillopsis subglobosa; Conrad, p. 22.

1866

Ancillopsis subglobosa; Conrad, p. 17.

1867

Ptychosalpinx altilis; Gill, p. 154.

1880

Ancillaria (Ancillopsis) subglobosa; Heilprin, p. 364.

1886

cf. Ancillaria subglobosa; Aldrich, p. 50, 51, 58.

1886

Expleritoma prima; Aldrich, p. 29, pl. 5, fig. 1.

non 1886

Ancillaria expansa; Aldrich, p. 28, pl. 5, fig. 11.

1890

Ancilla altilis; de Gregorio, p. 55, pl. 3, figs. 21, 22, 57, 62, 67.

1890

Ancilla subglobosa; de Gregorio, p. 56, pl. 4, figs. 3,4,19,20.

1890

Expleritoma prima; de Gregorio, p. 108, pl. 8, figs. 26, 27.

non 1890

Ancilla expansa; de Gregorio, p. 55, pl. 4, fig. 1 [copied Aldrich, 1886].

1893

Buccinanops altile; Cossmann, p. 33.

1893

Buccinanops subglobosum; Cossmann, p. 33.

1895b

Ancillaria subglobosa; Harris, p. 43.

1899

Buccinanops altile; Cossmann, p. 45.

1901b

Buccinanops (Brachysphingus) subglobosa; Cossmann, p. 221, pl. 9, fig. 14 [captions for figs 14 and 23 reversed].

1911

cf.? Buccinanops altile; Veatch and Stephenson, p. 295.

1921

Ancillopsis Tuomoyi [sic]; Aldrich, p. 12, pl. 1, figs. 23, 24.

1928

Bullia altile harrisi Palmer in Price and Palmer, p. 29, pl. 7, figs. 7, 11, 12, 15.

1928

Bullia altile; Palmer in Price and Palmer, p. 28, pl. 6, figs. 13, 14, 16.

1928

Bullia altile (B. subglobosum form); Palmer in Price and Palmer, p. 29, pl. 7, figs. 13, 14, 16.

1937

Bullia altilis; Palmer, p. 287, pl. 39, figs. 7–9.

1937

Bullia altilis subglobosa; Palmer, p. 289, pl. 39, figs. 1, 4, 5, 6, 11, 12, pl. 40, figs. 1–3, 5.

1937

Bullia altilis harrisi; Palmer, p. 290, pl. 39, figs. 2, 3, 10, 13.

1937

Lisbonia expansa Palmer [in part], p. 295, pl. 40, figs. 8, 12, 13.

1943

Lisbonia expansa; Wenz, p. 1227, fig. 3491 [copied Palmer, 1937].

1945

Ancillopsis subglobosa; Gardner, p. 199, pl. 22, figs. 20, 21.

1945

Ancillopsis harrisi; Gardner, p. 200, pl. 22, figs. 22, 23.

1947

cf. Bullia altilis; Harris and Palmer, p. 347, pl. 45, figs. 22, 23.

1947

cf. Bullia altilis subglobosa; Harris and Palmer, p. 348, pl. 45, fig. 24.

1953

Bulla [sic] altilis subglobosa; Wilbert, p. 99.

1960

Bullia altilis harrisi; Brann and Kent, p. 139.

1960

cf. Bullia altilis subglobosa; Brann and Kent, p. 139.

1960

Lisbonia expansa [in part]; Brann and Kent, p. 500.

1966

Bullia altilis harrisi; Palmer and Brann, p. 543.

1966

Bullia altilis subglobosa; Palmer and Brann, p. 543.

1966

Bullia tuomeyi; Palmer and Brann, p. 545.

1966

Lisbonia expansa [in part]; Palmer and Brann, p. 740.

1977

Bullia altilis; Dockery, p. 73, pl. 14, figs. 8, 9.

1977

Bullia altilis; Toulmin, p. 276, pl. 45, fig. 9.

1977

Bullia altilis subglobosa; Toulmin, p. 205.

1980

Bullia calluspira Dockery, p. 109, pl. 3, figs. 4–7.

1990

“Bullia” altilis; Allmon, p. 56, pl. 9, fig. 10.

1990

“Bullia” tuomeyi; Allmon, p. 59, pl. 9, fig. 13.

1996

Bullia altilis harrisi; Garvie, p. 74, pl. 15, figs. 1, 2.

2014

Bullia altilis subglobosa; Pacaud and Cazes, p. 18, pl. 1, figs. 4, 5, pl. 2, figs. 10, 11.

Figure 8. Ancillopsis. (1–20) Ancillopsis altilis: (1, 2) Ancillaria altile lectotype ANSP 14644; height 37.7 mm. (3, 4) Bullia altilis subglobosa hypotype PRI 3044; height 20.0 mm. (5, 6) Bullia altilis subglobosa hypotype PRI 3043; height 31.0 mm. (7, 8) Bullia calluspira holotype PRI 30022; height 27.0 mm. (9, 10) Bullia altilis hypotype PRI 3040; height 44.7 mm. (11–13) Expleritoma prima holotype USNM 638776: (11, 12) drawings from Aldrich (1886); (13) photo of broken specimen; height 36.0 mm. (14) Ancillopsis altilis (juvenile) PRI 4659; height 15.2 mm. (15, 16) Ancillopsis altilis ALMNH 15246; height 69.2 mm. (17, 18) Lisbonia expansa hypotype PRI 3047; height 78.4 mm. (19, 20) Bullia altilis subglobosa hypotype PRI 3037; height 26.6 mm. (21) Bullia altilis (juvenile) hypotype PRI 3039; height 27.0 mm. (22, 23) Ancillopsis patula (Bullia patula lectotype UCBL EM30549; height 28.0 mm; from Pacaud and Cazes, 2014).

Figure 9. Ancillopsis altilis (continued) and Ancillaria expansa. (1–10, 13, 14, 16, 17) Ancillopsis altilis: (1) Bullia altilis harrisi holotype PRI 360; height 15.3 mm. (2) Bullia altilis harrisi paratype PRI 356; height 16.8 mm. (3) Bullia altilis harrisi paratype PRI 357; height 20 mm. (4, 5) Ancillopsis altilis from Hatchetigbee Bluff, Alabama (Loc. AL-WA-1) PRI 104694; height 27.2 mm. (6–8) Ancillopsis tuomeyi holotype GSA-I17344; height 28 mm. (9, 10) Ancillopsis tuomeyi cotype GSA-I17579; height 23.2 mm. (11, 12) Ancillaria expansa holotype USNM 638775; height 51.4 mm. (13) Scanning electron micrograph of shell apex, Bullia altilis (juvenile) hypotype PRI 3039; height 27.0 mm. (14, 17) Scanning electron micrographs of shell apex, Ancillopsis altilis (juvenile) PRI 4659. (15) Scanning electron micrograph of shell apex, Ancillopsis patula PRI 83935. (16) Scanning electron micrograph of shell apex, Ancillopsis altilis PRI 83944.

Figure 10. Ancillopsis altilis (continued), Moodys Branch Formation, Mississippi (Loc. MS-YA-1). (1) MGS 2103 Height 25.0 mm. (2, 4, 5) MGS 2104 Height 29.0 mm. (3, 6, 7) MGS 2386 Height 36.0 mm. Photos provided by David Dockery.

Type material

Lectotype (plus 8 specimens) Ancillaria altile (selected by Palmer, 1937, p. 289 [fide Moore, 1962, p. 36]) ANSP 14644; holotype Anolax gigantea Lea, 1833, ANSP 5909 (lost; J. Sessa, personal communication, 11/12/21); holotype B. altilis harrisi PRI 360; paratypes PRI 356, 357; hypotype (Garvie, 1996) PRI 33127; holotype B. calluspira PRI 30022; hypotypes Lisbonia expansa (Palmer, 1937) PRI 3046, 3047; hypotypes B. altilis (Palmer, 1937) PRI 3038, 3040, 3042, juvenile specimen 3039; juvenile specimen (Harris and Palmer, 1947) PRI 4659; hypotypes B. altilis subglobosa (Harris and Palmer, 1947) PRI 4660; (Palmer, 1937) PRI 3037, 3038, 3043; holotype Ancillopsis tuomeyi GSA-I17344, cotype GSA-I17579; holotype Expleritoma prima Aldrich, 1886, USNM 638776.

Occurrence

Alabama: upper Paleocene (Thanetian), Nanafalia Formation, Bells Landing Marl, (AL-MO-3), lower Eocene (Ypresian), Bashi Marl, Hatchetigbee Formation (Locs. AL-CH-1, AL-CL-2, AL-CL-6, AL-WA-1), middle Eocene (Lutetian–Bartonian), Lisbon Formation, Gosport Sand (Locs. AL-CL-1, AL-CH-4, AL-MO-2, AL-MO-5, AL-PA-1); Mississippi: lower Eocene (Ypresian), Bashi Marl (Locs. MS-LA-1, MS-LA-2), upper Eocene (Bartonian–Priabonian), Moodys Branch Formation (Loc. MS-YA-1); Texas: middle Eocene (Lutetian–Bartonian), Cook Mountain, Reklaw, Weches formations (Locs. TX-BA-4, TX-MI-1); Arkansas: upper Eocene (Priabonian), White Bluff Formation (Loc. AR-ST-1). Mexico: middle Eocene (Bartonian), Laredo Formation (Loc. MX-NL-1), upper Eocene (Priabonian), Jackson Formation (MX-TA-1).

Revised description

Adult shell small to very large. Protoconch of 2–3 smooth whorls. Shell lanceolate with acute spire as juvenile, becoming rounded with lower spire with age. Spire in juveniles up to 0.25 total height, sometimes with faint axial ribs. In mature individuals, almost the entire ventral surface of shell covered by callus, with the early spire whorls sometimes barely or not at all protruding, producing a subspheroidal shape. Aperture lanceolate, 0.5–0.7 total shell height and ~0.5 maximum width. Posterior canal usually conspicuous. Shell smooth except for growth lines. Anterior and olivoid bands covered by callus near aperture, well developed on dorsal side of body whorl, with pronounced ridge between them. Growth lines prominent, straight, and sharply angled in olivoid band, deeply curved concavely toward the anterior notch in the anterior band. Plication plate covered by callus and not visible. Anterior tip of columella simple and pointed. Some large individuals show slight shouldering on posterior of body whorl.

Other material examined

PRI 64338 (1 specimen); PRI 83922 (10 specimens); PRI 83923 (1 specimen); PRI 83924 (1 specimen); PRI 83925 (4 specimens); PRI 83926 (2 specimens); PRI 83928 (1 specimen); PRI 83929 (1 specimen); PRI 83930 (1 specimen); PRI 83931 (15 specimens); PRI 83932 (3 specimens); PRI 83933 (1 specimen); PRI 83934 (16 specimens); PRI 83938 (4 specimens); PRI 83939 (1 specimen); PRI 83940 (1 specimen); PRI 83941 (1 specimen); PRI 83942 (1 specimen); PRI 83943 (2 specimens); PRI 83944 (1 specimen); PRI 83945 (1 specimen); PRI 83946 (12 specimens); PRI 104694 (1 specimen); ALMNH 15245 (27 specimens); ALMNH 15246 (1 specimen); MCZIP 24244 (53 specimens); MCZIP 29243 (21 specimens); MCZIP 29245 (1 specimen).

Morphometrics

We measured 10 variables on a total of 211 specimens from localities in Alabama, Mississippi, and France (Fig. 11; Supplement 2). Measurements were taken with digital calipers. Data were analyzed by factor analysis, using the 4M program in the BMDP statistical package (Dixon, 1993). The first three factors reported explained 91.6% of the total variation in the dataset. The results (Fig. 12) indicate that the specimens cannot be clearly separated morphologically, and therefore reasonably can be included in a single species-level taxon. The specimens measured included the type specimen of Bullia calluspira Dockery, 1980 (from the Bashi Formation), and the European species Buccinum patulum Deshayes, 1835 (see below), both of which are morphometrically clustered among the other specimens.

Figure 11. Measurements taken on specimens of Ancillopsis altilis for morphometric analysis. 1. Maximum height. 2. Maximum width in apertural view. 3. Width at posterior end of aperture. 4. Aperture length. 5. Height from posteriormost point of parietal callus. 6. Maximum height minus aperture length. 7. Maximum width of callus on ventral side. 8. Maximum width of aperture. 9. Width of anterior canal. 10. Maximum width from left side.

Figure 12. Results of factor analysis of morphometric data (Fig. 11; formations as indicated in Fig. 2; see Supplement 2 for data) from 211 specimens of Ancillopsis altilis. (1) Plot of scores on Factor 2 vs. Factor 3. (2) Plot of scores on Factor 1 vs. Factor 2.

Specimens from early in the history of the lineage (from the Tuscahoma, Bashi, and Hatchetigbee formations) do, however, differ in size and shape from those in the later Gosport Sand and Moodys Branch formations. Older specimens are smaller, and Gosport/Moodys specimens are larger (similar to the pattern reported in Agaronia alabamensis and other taxa; see Haveles and Ivany, 2010) (Figs. 13, 14). Price and Palmer (1928) described harrisi as a subspecies of altilis from the Queen City Formation at Smithville, Bastrop County, TX (Loc. TX-BA-4) (see Molineaux et al., 2013, about this locality), and Garvie (1996) reported it from the Reklaw Formation in Texas. Specimens of this form are especially small.

Figure 13. Anagenetic change in Ancillopsis altilis through time (formations as indicated in Fig. 2). (1) Shell height vs. shell width; (2) shell height vs. callus width; (3) shell height vs. aperture length. Measurements are in mm. See text for further discussion.

Figure 14. Height of Ancillopsis altilis through time (mean and +/− one standard deviation). Formations as indicated in Figure 2.

Shell shape and degree of callus lateral expansion over the body whorl also vary with time (Fig. 12). Specimens from the Bashi and Gosport are more inflated and have callus covering about half to three-fourths of the ventral side, while those from the Hatchetigbee are flatter and have callus on the entire ventral side and lapping over onto the dorsal side. Specimens from the Bashi, Hatchetigbee, and Queen City/Reklaw formations have low spires even as juveniles. The earliest known specimens, from the Greggs Landing bed of the Tuscahoma Formation (described as Ancillopsis tuomeyi Aldrich, 1921), are also distinctive in being dorso-ventrally flattened (Fig. 9.6–9.10).

Remarks

This is one of the most distinctive gastropods in the Eocene of the Gulf Coastal Plain. It has received a large number of names, which has unfortunately obscured rather than clarified its manifest morphological variability and disparity through its extended stratigraphic range. Significantly, the numerous named forms do not overlap with each other in time, suggesting a single variable lineage showing considerable anagenetic change through time rather than multiple separate taxa (Figs. 13, 14).

One of the most conspicuous characteristics of these forms is the greatly expanded parietal callus on adult individuals, frequently extending over the apex giving the shells an almost spherical overall shape (see Pietsch et al., 2021) (e.g., Figs. 8, 9). Juveniles, in contrast, have attenuated spires and only narrow extent of callus on the body whorl and spire (Fig. 8.14, 8.21). A series of specimens from the Moodys Branch Formation shows this ontogenetic transition particularly well (Fig. 10).

Several specimens from the Gosport Sand also show enormously thickened shell inside the last whorl ending at the aperture. This includes the type specimen of Explerotoma prima (USNM 638776; Fig. 8.11–8.13), which is now unfortunately badly damaged, and a specimen that Palmer assigned to Bullia altilis subglobosa (PRI 3037; Fig. 8.19, 8.20). Palmer (1937, p. 289) described these specimens as “injured or diseased” individuals of B. altilis subglobosa.

Palmer (1937) named the genus Lisbonia for Ancillaria expansa Aldrich, 1886. She stated that young specimens had axial ribs on their early whorls and were relatively uncallused, but that adult specimens, “rivalling in size B. altilis” were heavily callused. Indeed, a large specimen assigned to L. expansa by Palmer (1937; Fig. 8.16, 8.17) is almost identical to large specimens of altilis. Palmer noted that such ribbing did not occur on early whorls of altilis, and that “[t]he life histories of the two species are different and show that the two belong to two different genera” (Palmer, 1937, p. 295). She stated that the holotype of expansa (Fig. 9.11, 9.12) “has longitudinal nodes and fine, spiral lines on the apical whorls” (Palmer, 1937, p. 295). This is true, but these nodes are not the same as the longer longitudinal ribs present in other specimens, which are herein assigned to Anbullina elliptica (Whitfield, 1865) (see below). The holotype of Ancillaria expansa Aldrich (Fig. 9.11, 9.12), furthermore, has a very different overall shell shape compared to specimens assigned here to Ancillopsis altilis. The former has a very prominent and sharp rear edge of the anterior band, and no olivoid band. The widest part of the body whorl is just beneath the spire, rather than adjacent to the aperture. It is clearly not Ancillaria (see discussion below), and is more similar to Pseudoliva, except that it does not have the “pseudolivid groove” (see Vermeij, 1998), and may belong in the family Pseudolividae.

Ancillopsis patula (Deshayes, 1835)
Figures 8.22, 8.23, 9.15

non 1758

Buccinum patulum Linnaeus, 1758 (see Pacaud and Cazes, 2014, p. 17).

1835

Buccinum patulum; Deshayes, p. 646, pl. 88, figs. 5, 6.

1844

Buccinum patulum; Deshayes and Milne Edwards, p. 211, n. 10.

1850

Buccinanops palulum [sic]; d'Orbigny, p. 420, n. 1556.

1850

Pseudoliva ovalis Sowerby, p. 106, pl. 7, fig. 13.

1854

Pseudoliva ovalis; Morris, p. 274.

1854

Pseudoliva ovalis; Edwards, p. 451.

1855

Buccinum patulum; Pictet, p. 44, pl. 67, fig. 4.

1865

Buccinum patulum; Deshayes, p. 495, n. 2.

1871

Pseudoliva ovalis; Briart and Cornet, p. 40.

1889

Ancillaria cossmanni Mayer-Eymar, p. 324, n. 88, pl. 14, fig. 1.

1889

Buccinanops (Bullia) palulum [sic]; Cossmann, p. 134.

1890

Ancilla cossmanni; de Gregorio, p. 56.

1891

Pseudoliva ovalis; Newton, p. 167.

1893

Buccinanops (Bullia) palulum [sic]; Cossmann, p. 33.

1900

Buccinum (Buccinanops) palulum [sic]; Dollfus, p. 135.

1901a

Buccinanops (Brachysphingus) patulum; Cossmann, p. 48.

1901b

Buccinanops (Brachysphingus) palulum [sic]; Cossmann, p. 222.

1901b

Buccinanops patulum; Cossmann, p. 222.

1911

Buccinanops (Brachysphingus) palulum [sic]; Cossmann and Pissarro, pl. 36, fig. 175-1.

1937

Bullia patula; Palmer, p. 289.

1945

Ancillopsis patula; Gardner, p. 199.

1963

Bullia patula; Glibert, p. 98.

1990

“Ancillopsis” patula; Allmon, p. 86, pl. 9, fig. 12.

1995

Bullia patula; Le Renard and Pacaud, p. 114.

1995

Bullia patula; Pacaud and Le Renard, p. 167.

1996

Ancillopsis patula; Tracey et al., p. 120.

1997

Ancillopsis patula; Squires, p. 850.

2014

Bullia patula; Pacaud and Cazes, p. 17, text-fig. 1, pl. 1, figs. 1–3; pl. 2, figs. 1–9.

Type material

Lectotype UCBL EM30549.

Occurrence

France: upper Eocene (Auversian); UK: upper Eocene, Bracklesham Beds, Selsey Formation (Loc. UK-WS-1).

Revised description

The shell is medium in size, oval, plump, with rounded curve at the back, dorso-ventrally depressed, with thick test. The spiral is short, pointed, composed of 3–4 very narrow whorls, separated by simple sutures and disturbed by the increments (disrupted by growth lines?). The whole of the teleoconch is devoid of sculpture; we observe only strong and numerous streaks of weakly opisthocyrtic growth lines, strongly sinuous in the peri-sutural adapical region, intersected by very fine barely visible spiral streaks. The body whorl, very large, constituting by itself almost the entire total height, shows a particularly convex profile; it ends without a neck, by a broad, clearly delimited fasciole. The body whorl presents in the abapical region above the fasciole, a wide band, slightly depressed, inducing a wide furrow on the edge of the labrum corresponding to the deviation of the streaks of growth. This band is separated from the fasciole by a space equal in width to the abapical band. The opening is large, ovoid, dilated, broad in front, narrow in the back, and terminated by a short and narrow anal canal. The columella, clearly excavated over the entire height, ends in an acute point; the columella also is cut by a wide and deep siphonal notch. The parietal and columellar calluses are thick, very widely spread laterally. The labrum is thin, smooth on the inside, slightly prosocline (translation of Pacaud and Cazes, 2014, p. 17–18).

Other material examined

PRI 83935 (1 specimen) (Loc. FR-1).

Remarks

As noted by Palmer (1937, p. 289), Allmon (1990, p. 86), and Squires (1997), Ancillopsis patula is almost identical to Ancillopsis altilis from the U.S. Gulf Coast in its subspherical but dorsoventrally flattened shape, minute spire, inflated, unsculptured body whorl, large aperture, expanded callus, and lack of terminal columellar fold; and in our morphometric analysis, it falls among Coastal Plain specimens (Fig. 12). It differs in being smaller than specimens of A. altilis of similar geological age and having a shinier shell (which might be partly an artifact of preservation). The most significant difference between the two species may be their pattern of remnant color on the body whorl; A. patula shows an olivoid band that appears purplish under UV light, whereas A. altilis does not (Pacaud and Cazes, 2014, p. 21).

As noted by Pacaud and Cazes (2014, p. 16), the species also exists in the Bartonian in England where it had been erroneously assigned to the genus Pseudoliva and described as Pseudoliva ovalis (Briart and Cornet, 1871; Newton, 1891). As the only representative of this clade outside of the Gulf Coast, this species has interesting paleobiogeographic implications.

Pacaud and Cazes (2014) argued that patula should be retained in Bullia in Nassariidae. Neither patula nor altilis, however, have terminal columellar folds, which are characteristic of all modern members of Nassariidae (Allmon, 1990; see Fig. 7).

Genus Anbullina Palmer, 1937

Type species

Ancillaria ancillops Heilprin, 1891, by original designation (Palmer, 1937, p. 292).

Diagnosis

Shell oval to lanceolate; spire low but acute. First three or four teleoconch whorls longitudinally ribbed, ribs becoming obsolete on later whorls of spire and body whorl. Spire and body whorls frequently slightly shouldered. Body whorl bears narrow band below suture, which bears sigmoidal growth lines of growth. Plication plate and anterior band faint to pronounced. Parietal callus extends less than halfway across ventral surface of body whorl, and only slightly posterior of aperture. Olivoid band present but faint. Anterior notch moderate to deep.

Remarks

Palmer (1937) named Anbullina for the distinctive species Ancillaria ancillops Heilprin, 1891. This species was allied with the Bullia group in Nassariidae by Cossmann (1901b), who placed it in the genus Buccinanops, and Palmer proposed Anbullina as a subgenus within Bullia Gray, 1834. Its similarities to these genera of Nassariidae, however, consist of little more than overall shape (Allmon, 1990, p. 59). On the other hand, it shares with other ancillariids an (albeit very faint) olivoid band and (well-developed) anterior band. It therefore seems more likely assignable to the ancillariids, but does not agree with any other genus in that family. Recognition of a second species, Anbullina elliptica (Whitfield, 1865), further justifies continued recognition of a separate genus-level taxon.

Anbullina ancillops (Heilprin, 1891)
Figure 15.1, 15.2

1891

Ancillaria ancillops Heilprin, p. 398, pl. 11, fig. 4.

1901b

Buccinanops (Bullia) ancillopsis [sic]; Cossmann, p. 223, pl. 9, fig. 24.

non 1901b

Anaulax ancillopsis; Cossmann, p. 223.

1937

Bullia (Anbullina) ancillops; Palmer, p. 292, pl. 40, figs. 4, 6.

1943

Bullia (Anbullina) ancillops; Wenz, p. 1226, fig. 3488 [copied Palmer, 1937, pl. 40, fig. 6].

1980

Bullia cf. B. (Anbullina) ancillops [misspelled in plate caption as “Bucilla cf. (Anbullina) Ancillops”]; Dockery, p. 110, pl. 17, fig. 4.

1990

“Bullia” (Anbullina) ancillops; Allmon, p. 59, pl. 9, fig. 4.

Figure 15. Anbullina. (1, 2) Anbullina ancillops: Bullia (Anbullina) ancillops hypotype PRI 3045; height 28.8 mm. (3–10, 12, 16–18) Anbullina elliptica: (3) Anbullina elliptica (Buccinanops ellipticum hypotype [Barry and LeBlanc, 1942] LSU 6023; height 27.5 mm). (4, 5) Pseudoliva elliptica, holotype FMNH-UC 24670; height 17 mm. (6) Bullia sp. (from Dockery, 1980, pl. 37, fig. 7), MGS 523; height 11 mm. (7, 8, 18) “Buccinanops” ellipticum reklawensis holotype PRI 30410; height 23.5 mm); (18) scanning electron micrograph of shell apex. (9, 10) Anbullina elliptica (Lisbonia expansa hypotype [Palmer, 1937] PRI 3046; height 25 mm). (11) Bucilla [sic] cf. B. (Anbullina) ancillops (from Dockery, 1980, pl. 17, fig. 4), MGS 110; height 20.7 mm. (12, 16, 17) Anbullina elliptica, specimen from Bells Landing, AL (Loc. AL-MO-3), PRI 83937; height 18.4 mm; (16, 17) scanning electron micrographs of shell apex. (13) Anbullina elliptica? (Pseudoliva ostrarupis pauper holotype NPL 35590); height 18 mm. (14, 15) Anbullina elliptica? (Lisbonia pauper NPL 37825); height 13.2 mm.

Type material

Holotype lost (fide Palmer, 1937, p. 293); hypotype (Palmer, 1937) PRI 3045.

Occurrence

Texas: middle Eocene, Weches Formation (Loc TX-BA-1).

Revised description

Shell lanceolate; spire low but acute. Protoconch of 1.5 whorls, smooth, rounded; first protoconch whorl flatly convex; first three or four teleoconch whorls longitudinally ribbed, the ribs becoming obsolete on the later whorls of the spire and the body whorl, which are smooth. Body whorl with narrow band below suture, which bears sigmoidal growth lines. Plication plate with sharp rear edge forming slight false umbilicus and square anterior edge; anterior notch deep.

Other material examined

PRI 57311 (1 specimen).

Remarks

Anbullina ancillops is known only from one locality, the now-inaccessible Smithville outcrop of the Weches Formation in Texas (Loc. TX-BA-1). Dockery (1980, p. 110, pl. 17, fig. 4) figured a poorly preserved specimen from the Doby's Bluff Tongue (see Fig. 3) in Mississippi and assigned it to “Bullia cf. B. (Anbullina) ancillops.” This specimen (see Figure 15.11), however, has a relatively longer and wider aperture than the type of ancillops, the spire appears to be partially covered with parietal callus, and it lacks the distinctive anterior end of the columella. It somewhat resembles modern and fossil species of Baryspira from New Zealand (see Beu et al., 1990), and resembles no other form in the Coastal Plain. No other similar specimens have been found in the Doby's Bluff (Dockery, personal communication, November 2, 2021). It may represent yet another otherwise unrecorded ancillariid lineage in the region.

Anbullina elliptica (Whitfield, 1865)
 Figure 15.3–15.10, 15.12, 15.16–15.18

1865

Pseudoliva elliptica Whitfield, p. 260.

1886

Pseudoliva elliptica; Aldrich, p. 56.

1887

Pseudoliva elliptica; Aldrich, p. 80 [not “1897” as in Harris, 1899a, and Barry and LeBlanc, 1942].

non 1895a

Pseudoliva ostrarupis pauper Harris, p. 76, pl. 8, fig. 4.

1896

Pseudoliva ostrarupis pauper; Harris, p. 99, pl. 9, fig. 20.

1899a

Buccinanops ellipticum; Harris, p. 30, pl. 3, figs. 14, 15.

1899b

Buccinanops ellipticum; Harris, p. 305, pl. 54, figs. 4, 5.

1923

Pseudoliva ostrarupis pauper; Trowbridge, p. 96.

1933

Pseudoliva ostrarupis pauper; Plummer, p. 581.

1935

Pseudoliva ostrarupis pauper; Gardner, p. 317.

1937

Lisbonia expansa (Aldrich) [in part]; Palmer, p. 295, pl. 40, figs. 8, 12, 13.

1942

Buccinanops ellipticum; Barry and LeBlanc, p. 117, pl. 15, figs. 1, 2.

1945

Pseudoliva elliptica; Gardner, p. 195, pl. 27, figs. 3, 4.

1945

Pseudoliva ostrarupis pauper; Gardner, p. 195.

1960

Buccinanops ellipticum; Brann and Kent, p. 134.

1966

Buccinanops ellipticum; Palmer and Brann, p. 533.

1990

“Buccinanops” ellipticum; Allmon, p. 59, pl. 9, fig. 8.

1996

“Buccinanops” ellipticum reklawensis Garvie, p. 74, pl. 15, figs. 14, 15.

?2013

Lisbonia pauper; Garvie, p. 4, pl. 7, figs. 14, 15.

Type material

Holotype FMNH-UC 24670; hypotype (Barry and LeBlanc, 1942) LSU 6023; holotype “Buccinanops” ellipticum reklawensis, PRI 30410; holotype Pseudoliva ostrarupis pauper TMM BEG 35590; hypotypes (Garvie, 2013) TMM NPL 37825, 37826.

Occurrence

Texas: upper Paleocene (Selandian), Solomon Creek Member, Seguin Formation (Loc.TX-BA-2), upper Paleocene (Thanetian), Pendleton Formation (Loc. TX-SA-1), lower Eocene (Ypresian), Reklaw Formation (Loc. TX-MI-1); Louisiana: upper Paleocene (Selandian), Marthaville Formation (Locs. LA-NA-1, LA-SA-1, LA-SA-2); Alabama: upper Paleocene (Thanetian), Bells Landing Marl (Loc. AL-MO-3); middle Eocene (Lutetian–Bartonian), Lisbon Formation (Loc. AL-MO-5); Mississippi: upper Eocene (Bartonian–Priabonian), Moodys Branch Formation (Loc. MS-NE-1).

Revised description

Shell medium sized, lanceolate to elliptical in shape, with an evenly curved profile attenuated at both apical and anterior ends. Protoconch incompletely known, but probably of 2–3 smooth whorls. Spire relatively low, comprising not more than one-fourth the total height, while the aperture comprises more than one-half the total height. Spire usually bears numerous faint straight axial ribs on early teleoconch whorls. Sculpture on body whorl lacking, other than growth lines. Olivoid band faint to pronounced. In the holotype, this band takes the form of an adapertural angular deflection of the growth lines, forming shallow chevrons. Specimens from the Moodys Branch Formation of Mississippi show a single shallow groove 1–2 mm wide. Body whorl may show minor shouldering beneath spire or be smoothly tapered. Posterior margin of parietal callus usually even with posterior end of aperture, rarely extending to spire. Anterior notch deep.

Other material examined

PRI 83936 (3 specimens); PRI 83937 (1 specimen).

Remarks

Whitfield (1865) stated that his type specimen (Fig. 15.4, 15.5) came from Vicksburg, Mississippi, but Aldrich (1887, p. 80; see Palmer and Brann, 1966, p. 533) argued that it likely came from the Bells Landing Marl Member of the Tuscahoma Formation in Alabama (AL-MO-3) (see Fig. 2), where other very similar specimens have been found (see Fig. 15.12). This variable species includes specimens that have been placed in a variety of taxa, including those identified by Palmer (1937) as juveniles of her Lisbonia expansa (see above, under Ancillopsis altilis).

Adults of Anbullina elliptica are similar to juveniles of Ancillopsis altilis (compare Figs. 8.14, 8.21, 10.1, 10.2 with 15.1–10, 15.12). Our phylogenetic analysis shows that the two species are closely related (Fig. 5).

Price and Palmer (1928, p. 23) listed but did not figure “Bullia sp. aff. ellipticum Whitefield” (sic) from Smithville, TX (Loc. TX-BA-1). Garvie (2013, p. 44–45) placed Pseudoliva ostrarupis pauper in the genus Lisbonia, arguing (based on material he said was in his collection but did not figure) that the genus is valid (see discussion of Lisbonia above under Ancillopsis altilis). The hypotype of Lisbonia pauper (NPL 37825) figured by Garvie (2013) shows axial ribs on the early teleoconch whorls, and may belong here, but the holotype of Pseudoliva ostrarupis pauper Harris, 1895a (NPL 35590; Fig. 15.13) lacks axial ribs, and may belong to Pseudoliva.

Genus Eoancilla Stephenson, 1941

Type species

Eoancilla acutula Stephenson, 1941, by original designation.

Diagnosis

From Garvie's (2013, p. 59) diagnosis: “Shell with high, smooth, evenly tapering spire; protoconch smooth, blunt, of 2 ¾ whorls; tip minute, partially immersed; callus band covering approximately lower 70% of spire whorls; columella strongly twisted; fasciolar band with 5–8 oblique narrow lirae, usually posterior ancillid band, and groove; anterior notch deep, internally thickened with callus; small low ridge of callus continuing posteriorly up inside of outer lip for ca. 1/3 of its height; small labral denticle present at end of line or kink in growth lines running from posterior end of aperture.”

Remarks

Stephenson described Eoancilla based on a Late Cretaceous species from Texas. As summarized by Garvie (2013, p. 59–60), Sohl (1964) synonymized Eoancilla with Ancillus Montfort, 1810, the type species of which is A. buccinoides Lamarck, 1803, from the Lutetian of the Paris Basin, “on the basis of the shared glazed whorls, the blunted apex, and apertural features.” Garvie (2013, 2021) argued that Eoancilla was distinct from Ancilla. He also described two additional Paleocene species from Texas and Alabama, assigned the Paleocene species Olivella mediavia Harris, 1896, to Eoancilla, and said that he had “several specimens of Eoancilla, or a close relative thereof, from the middle Claibornian Weches Formation” (Garvie, 2013, p. 61), which he did not figure. He suggested that Eoancilla can “be taken as an ancestral Upper Cretaceous ancillid taxon that by Middle Eocene times had already spread to the Nangulaan Eocene of Java, because A. songoensis Martin, 1914… is remarkably close to A. mediavia” (Garvie, 2013, p. 61).

Eoancilla acutula Stephenson, 1941
Figure 16.1, 16.2

1941

Eoancilla acutula Stephenson, p. 361, pl. 69, figs. 8, 9.

1964

Ancilla (Ancillus) acutula; Sohl, p. 248, pl. 36, figs. 1–7, 10.

Figure 16. Eoancilla. (1, 2) Eoancilla acutula holotype USNM 77126 (from Stephenson, 1941); height 9.3 mm. (3, 4) Eoancilla lapicidina holotype NPL 93694 (from Garvie, 2021); height 11.1 mm. (5) Eoancilla mediavia (Olivella mediavia, drawing from Harris, 1896, of specimen in USNM). (6, 7) Eoancilla mediavia PRI 57647; height 17.4 mm. (8, 9) Eoancilla hordea holotype NPL 37709 (from Garvie, 2013); height 11.5 mm.

Type material

Holotype USNM 77126; paratype USNM 77127; hypotypes (Sohl, 1964) USNM 130465–130467.

Occurrence

Texas: Upper Cretaceous (Maastrictian), Kemp Clay (Loc. TX-TR-1); Mississippi: Upper Cretaceous (Maastrictian), Owl Creek Formation (Locs. MS-TI-1, MS-TI-2); Tennessee: Upper Cretaceous (Maastrictian), Clayton Formation (Owl Creek Formation reworked into base) (Loc. TN-HA-1).

Original description

(Stephenson, 1941, p. 361) “Shell small, polished, with maximum inflation at about the midheight, from which region the surface slopes gently toward each extremity. Protoconch small smooth, trochoid, coiled about twice. Whorls four. Spire acute and a little less than half the total height of the shell; spiral angle about 45 degrees at the tip decreasing to about 40 degrees on the whorls below. Sides of whorls of spire nearly flat; the lower 7/10 of the surface of the penultimate whorl is covered with a smooth, nontumid, closely appressed band of callus, which is separated from the upper edge of the body whorl by a fine, sharp, slightly incised, but not canaliculate, suture; the upper edge of the band is gently undulating, but the band extends with about the same proportional width all the way back to the protoconch. The main surface of the shell is smooth, except for growth lines and an exceedingly faint indication of fine spiral lines, and one fine spiral groove at about the position of the periphery. The growth lines cross the body whorl in a gently sinuous trend, bending sharply backward before they join the suture above, and more gently backward near their junction with a sharply incised groove on the base below. The aperture is lenticular with a narrow, sharply upturned, posterior canal, and widens anteriorly to a short, wide, deeply notched, siphonal canal. Outer lip broadly arcuate and notched at the suture above; inner lip broadly excavated and forming on the parietal wall a band of callus which spreads forward a little and extends upward, becoming thicker in front of the posterior canal; this callus spreads upward across about 7/10 of the surface of the penultimate whorl and is continued backward forming the band of callus on that whorl already described. The columella is flattened anteriorly and is ornamented with a band of 7 or 8 closely spaced, small, narrow oblique ridges which continue forward on the sharply twisted anterior fasciole to the terminus of the shell. The anterior fasciole is bordered on the outer side by a deep, wide, round-bottomed spiral sulcus which is traceable backward until it is covered by the callus of the lip; the anterior edge of the callus of the inner lip follows down the bottom of the sulcus to the terminus of the shell; the sulcus is bordered in front on the base of the shell by a wide, smooth band which is limited both above and below by narrow sharply incised grooves.”

Remarks

This is the only Cretaceous species treated here and may be among the oldest known species of Ancillariidae.

Eoancilla hordea Garvie, 2013
Figure 16.8, 16.9

2013

Eoancilla hordea Garvie, p. 61, pl. 11, figs. 6, 7.

Type material

Holotype TMM NPL 37709; paratype TMM NPL 37710.

Occurrence

Texas: upper Paleocene (Selandian), Seguin Formation (Loc. TX-BA-2).

Original description

(Garvie, 2013, p. 60) “Shell small, subcylindrical, smoothly rounded, barely contracted at suture; protoconch of ca. 2 whorls; tip somewhat oblique, partially immersed, with no demarcation transition to teleoconch whorls; suture defined by impressed line; spire whorls mostly covered with enamel-callus band; aperture slightly larger than ½ shell Height; columella spirally twisted; fasciolar band with 6 oblique narrow lirae; ancillid band wide; groove prominent; anterior notch deep, internally thickened with callus; thin line of callus continuing posteriorly up inside of outer lip; labral denticle small.”

Remarks

This species is known from 23 specimens from the type locality (Garvie, 2013, p. 61).

Eoancilla lapicidina Garvie, 2021
Figure 16.3, 16.4

2021

Eoancilla lapicidina Garvie, p. 138, pl. 14, figs. 11, 12.

Type material

Holotype TMM NPL 93694; paratype TMM NPL 93695.

Occurrence

Texas: lower Paleocene (Danian), Kincaid Formation (Loc. TX-FA-1).

Original description

(Garvie, 2021, p. 139) “Shell small to medium sized, whorls feebly concave on upper half, feebly convex below; whorls covered with a light coating of callus; columella not or only weakly twisted, with 7 spiral ridges margined by a deep sulcus, sulcus forming the anterior part of the lower anterior band, upper anterior band well defined and posteriorly margined by a minute, impressed line, line only visible near the aperture, rapidly becoming obsolete adaperturally; olivid groove and band not visible; secondary callus thick where margining the upper part of the aperture, rapidly thinning and becoming the convex part of the spire, although not easily differentiated; protoconch of 2 whorls, somewhat flattened, and set at a slight angle to the shell axis.”

Remarks

This species is known from 18 specimens from the type locality (Garvie, 2021, p. 139).

Eoancilla mediavia (Harris, 1896)
Figure 16.5–16.7

1896

Olivella mediavia Harris, p. 80, pl. 7, fig. 19.

non 1897

Olivella mediavia; Harris, p. 29, pl. 3, fig. 12 (fide Palmer and Brann, 1966, p. 486).

1899

Ancilla (Sparella) mediavia; Cossmann, p. 62.

1935

Olivella mediavia; Gardner, p. 230.

1966

Agaronia mediavia; Palmer and Brann, p. 486.

2021

Eoancilla mediavia; Garvie, p. 139.

Type material

Holotype lost (fide Palmer and Brann, 1966, p. 487).

Occurrence

Alabama: upper Paleocene (Selandian–Thanetian), Matthews Landing Marl, Bells Landing Marl (Locs. AL-MO-3, AL-SU-3, AL-WI-1, AL-WI-2).

Original description

(Harris, 1896, p. 80) “…whorls about 7; the first extremely small, the second much larger, and the third still greater, producing a blunt appearance; remaining spiral whorls nearly or quite covered by the sutural callosity; body whorl smooth, but the direction of the lines of growth can be traced with a glass; growth lines slightly geniculated about three-fourths of the way from the suture to the anterior folds at a faint depression which produces a faint tooth on the margin of the outer lip; columella well twisted below where it is 7–8 striate; above on the columella there is often a large obtuse fold which marks a former position of the upper margin of the slit for the anterior canal.”

Other material examined

PRI 57647 (Bell's Landing, AL; Loc. AL-MO-3).

Remarks

The type specimen was from Matthews Landing, AL (Loc. AL-WI-2). Gardner (1935, p. 230) said that this species “is widespread and fairly common” and Palmer and Brann (1966) listed it as coming from several other Alabama localities. Garvie (2013, p. 60–61) argued that its multispiral protoconch, callus that covers only a portion of the teleoconch whorls, and the lower inner lip callus support placing it in Eoancilla. Our phylogenetic analysis (see below) indicates that this species may be ancestral to Olivula staminea (Conrad, 1832).

Genus Monoptygma Lea, 1833

Type species

Monoptygma alabamiensis Lea, 1833, by subsequent designation (Cossmann, 1899).

Remarks

The name Monoptygma has a complicated history. It was first proposed by Isaac Lea (1833) for two fossil species from the Eocene of Alabama (M. alabamiensis and M. elegans), which do not especially resemble each other (Fig. 17.7, 17.8). G.B. Sowerby II (1839, p. 66) listed “Monoptygma Lea”, but as including only “M. elegans,” with a copy of Lea's illustration. Four lines later, he listed “Monotigma Gray” with no species name and referenced his figure 371, which shows a very different shell. According to van Aartsen and Hori (2006, p. 3), however, “there is no indication of involvement of Gray in Sowerby's Manual,” and so “one has to consider Sowerby, 1839, as the author of Monotigma.” Gray (1847, p. 140, 159), citing “J. Lea,” distinguished “Monop. alabamiensis, J. Lea” and “?Monoptygma sp. Lea” from “Monotigma or Monotygma, G. Sowerby,” the latter containing “Mon. elegans, Lea,” and assigned the former to Pyramidellidae. Adams (1853, 1854), however, used Monoptygma for several modern species in Pyramidellidae. This was repeated by Smith (1872) and Mörch (1875). van Aartsen (1986) untangled these names, clarifying that Monoptygma Lea is a valid genus, and that Monotygma and Monotigma are both valid and distinct genera of pyramidellids.

Figure 17. Monoptygma lymneoides. (1, 2) Monoptygma leai PRI 3026; height 22 mm. (3, 4) Monoptygma lymneoides PRI 3036; height 35 mm. (5, 6) Monoptygma crassiplica ANSP 13274; height 17 mm. (7) Monoptygma alabamiensis, drawing from Lea (1833). (8) Monoptygma elegans, drawing from Lea (1833) (not Monoptygma). (9) Monoptygma crassiplica, drawing by G.D. Harris (from Palmer, 1937, pl. 38, fig. 4) of USNM specimen. (10) Monoptygma curta holotype ANSP 15618; height 11.6 mm. (11, 12) Monoptygma crassiplica hypotype PRI 3027; height 22.4 mm. (13, 14) Monoptygma alabamiensis paratype ANSP 5930; height 8.2 mm. (15, 16) Monoptygma alabamiensis holotype ANSP 5929; height 12 mm. (17) Monoptygma leai syntype FMNH 24671; height 19 mm. (18) Monoptygma crassiplica, drawing from Gabb (1860).

Although some authors (e.g., Gabb, 1872) placed Monoptygma in Olividae, Palmer (1937, p. 296) allied it with Bullia in Nassariidae, writing that “[t]he columella is smooth as in Bullia.” This was accepted by Glibert (1963). Cernohorsky (1984, p. 27) seemed to be agnostic about the placement in Nassariidae, writing that “Monoptygma lacks any characters which would suggest a relationship with the Dorsaninae” in Nassariidae.

Monoptygma (which means “single fold”) is characterized by a single (very rarely double) fold or plication on the inner apertural lip. All species also show an olivoid band wrapping around the lower part of the body whorl. This combination of characters is unique and makes this taxon somewhat puzzling. Careful examination of all available specimens, however, indicates that the fold is continuous with the plication plate, and is therefore not homologous to the “columellar folds” of other taxa, such as species of Volutidae. We therefore conclude that it is assignable to Olividae.

The genus Monoptygma has been oversplit, and several species are represented by few or poorly known specimens. We synonymize all described forms into one somewhat variable species.

Monoptygma lymneoides (Conrad, 1833)
Figure 17.1–17.7, 17.9–17.18

1833

Ancillaria lymneoides Conrad, p. 44.

1833

Monoptygma alabamiensis Lea, p. 186, pl. 6, fig. 201.

1834b

Ancillaria lymneoides; Conrad, p. 5.

1835

Ancillaria lymneoides; Conrad, p. 42, pl. 16, fig. 6.

1849

Ancillaria lymneoides; Lea, p. 96.

1850

Ancyllaria [sic] lymneoides; d'Orbigny, p. 352.

1854

Ancilla lymneoides; Conrad, p. 30.

1860

Monoptygma crassiplica Conrad in Gabb, p. 384, pl. 67, fig. 37.

1865a

Monoptygma crassiplica; Conrad, p. 22.

1865a

Monoptygma alabamiensis; Conrad, p. 22.

1865a

Monoptygma curta Conrad, p. 22.

1865a

Monoptygma lymneoides; Conrad, p. 23.

1865b

Monoptygma curta; Conrad, p. 143, pl. 11, fig. 8.

1865

Monoptigma [sic] leai Whitfield, p. 261, pl. 27, fig. 7.

1866

Monoptygma curta; Conrad, p. 17.

1866

Monoptygma lymneoides; Conrad, p. 17.

1866

Monoptygma curta; Conrad, p. 17.

1866

Monoptygma alabamiensis; Conrad, p. 17.

1866

Monoptygma crassiplica; Conrad, p. 17.

1883

Monoptygma lymneoides; Tryon, p. 61, pl. 3, fig. 23.

1887

Monoptygma leai; Aldrich, p. 80.

1890

Monoptygma alabamiensis; de Gregorio, p. 58, pl. 4, fig. 10.

1890

Ancilla (Monoptygma) curta; de Gregorio, p. 58, pl. 4, fig. 11 [copied Conrad, 1865b, pl. 11, fig. 8].

1890

Ancilla (Monoptygma) Alabamiensis; de Gregorio, p. 58, pl. 4, fig. 10 [copied Lea, 1833, pl. 6, fig. 201].

1890

Ancilla (Monoptygma) lymneoides; de Gregorio, p. 58, pl. 4, fig. 14 [copied Conrad, 1835, pl. 16, fig. 6].

1890

Monoptygma curta; de Gregorio, p. 58, pl. 4, fig. 11.

1891

Monoptygma crassiplica; Heilprin, p. 398.

1893

Monoptygma limneoides [sic]; Cossmann, p. 41.

1895b

Monoptygma curta; Harris, p. 14.

1895b

Ancillaria lymneoides; Harris, p. 26.

1899

Monoptygma curta; Cossmann, p. 72.

1899

Monoptygma limneoides [sic]; Cossmann, p. 71, pl. 3, figs. 24, 25.

1937

Monoptygma crassiplica; Palmer, p. 298, pl. 38, figs. 3–5.

1937

Monoptygma lymneoidies [sic]; Palmer, p. 296, pl. 38, figs. 19, 20, pl. 85, figs. 3, 7.

1937

Monoptygma curta; Palmer, p. 298, pl. 85, fig. 8.

1937

Monoptygma leai; Palmer, p. 297, pl. 38, figs. 1, 2, 6, 8.

1943

Monoptygma lymneoides; Wenz, p. 1227, fig. 3492 [copied Palmer, 1937, pl. 38, fig. 19].

1945

Monoptygma leai; Gardner, p. 195, pl. 27, figs. 2, 5.

1960

Monoptygma leai; Brann and Kent, p. 567.

1966

Monoptygma leai; Palmer and Brann, p. 779.

1966

Monoptygma curtum; Palmer and Brann, p. 779.

1966

Monoptygma crassiplicum; Palmer and Brann, p. 778.

1990

Monoptygma crassiplicum; Allmon, p. 61.

1990

Monoptygma curtum; Allmon, p. 61.

1990

Monoptygma leai; Allmon, p. 60, pl. 9, fig. 9.

1990

Monoptygma lymneoides; Allmon, p. 60.

Type material

Conrad (1832–1835) apparently did not designate a holotype for M. lymneoides (see Moore, 1962, p. 72); lectotype (ANSP 15619) selected by Palmer (1937, p. 297) with eight other specimens under the same number (all apparently lost; J. Sessa, personal communication, 11/12/21); holotype M. alabamiensis Lea, ANSP 5929; paratype ANSP 5930; hypotype (Palmer, 1937), PRI 3036; holotype M. curta ANSP 15618; syntypes Monoptygma leai FMNH-UC 24671 (5 specimens); hypotype (Palmer, 1937) PRI 3026; Conrad's holotype Monoptygma crassiplica probably lost (fide Palmer, 1937, p. 298; Moore, 1962, p. 51); hypotype (Palmer, 1937) PRI 3027.

Occurrence

Alabama: middle Eocene (Lutetian–Bartonian), Upper Lisbon Formation, Gosport Sand (Locs. AL-MO-2a, AL-MO-5); Texas: middle Eocene (Ypresian–Luettian), Weches Formation, Stone City Beds (Loc. TX-BA-1, TX-RO-1); Louisiana: middle Eocene (Lutetian–Bartonian), Cook Mountain Formation (LA-BI-1, LA-OU-1).

Revised description

Shell lanceolate in shape, with aperture equal to about two-thirds of shell height. Protoconch unknown. Body whorl profile usually grades smoothly into spire profile, but occasionally slightly shouldered. Single distinct columellar fold on the middle of the parietal lip. Spire slightly acuminate, with faint axial ribbing on adapical margins of the whorls. Spire sutures moderately callused. Parietal callus moderately developed, extending about one-half to one-third of the way across the body whorl and about halfway between posterior end of aperture and suture. Faint anterior band, consisting of slight deflection of the growth lines, on body whorl, sometimes with faint ridge on posterior edge. Anterior end of body whorl ends in a simple tapered point.

Other material examined

PRI 56353 (7 specimens); MCZIP 29252 (1 specimen); MCZIP 29247 (1 specimen); ANSP 13274 (1 specimen); PRI 104504 (2 specimens); PRI 83948 (1 specimen); PRI 104514 (2 specimens).

Remarks

Monoptygma lymneoides has been oversplit; the various named forms mostly do not overlap in time and grade into one another, forming a single variable lineage. Monoptygma lymneoides from the upper middle Eocene Gosport Sand is the largest form. Monoptygma curta, also from the Gosport, is known only from the holotype. Palmer (1937, p. 298) said that it “differs from the young of M. lymneoides in being broader and shorter” but also closely resembles some specimens of M. leai from the underlying Cook Mountain/Lisbon formations. Palmer (1937, p. 297) described M. leai as “beautiful and distinct,” but it intergrades with specimens of M. lymneoides (compare Fig. 17.1–17.4). Monoptygma crassiplica occurs in the middle Eocene Weches and Stone City beds in Texas and the Cook Mountain Formation of Louisiana. It also intergrades with M. lymneoides. Palmer (1937, p. 298) mentioned that a specimen of crassiplica “in the U.S. Nat. Museum from Holstein's well, 5 miles southeast of Gibbsland, Bienville Parish, La. was drawn by G.D. Harris for his Texas Eocene MS” and published that figure as her pl. 38, fig. 4. We have not been able to locate Harris’ specimen, and the drawing is reproduced here as Figure 17.19. The specimen ANSP 5929 (Figure 17.15, 17.16) was listed as the holotype of Monoptygma alabamiensis by Palmer (1937, p. 297). A query (“?”) was added to this designation in Palmer and Brann (1966, p. 780). The specimen generally resembles Lea's figure (1833, pl. 6, fig. 201), but the apex may have been damaged.

As explained by Wheeler (1935, p. 103–105), Conrad (1833) was published on August 29, while Lea (1833) was published on December 2, therefore Conrad's name lymneoides has priority.

Genus Olivula Conrad, 1832

Type species

Ancillaria staminea Conrad, 1832, by subsequent designation Cossmann (1899, p. 70).

Remarks

Lamarck (1811) proposed the name Ancillaria, but it is generally synonymized with Ancilla Lamarck, 1799 (e.g., Kilburn, 1981, p. 358). In 1832, Conrad proposed the species Ancillaria staminea from the Claibornian Eocene of Alabama and said that it closely resembled Ancillaria canalifera (Lamarck, 1803), from the Eocene of France. But he then suggested (Conrad, 1832, p. 25) that “[t]hese two species do not correspond entirely with the genus Ancillaria, as the aperture is much longer, the shells are striated, and the suture is somewhat channeled;” he therefore stated that these two species “might constitute a separate genus by the name of Olivula.” Cossmann (1899, p. 70) designated A. staminea Conrad as the type species of Olivula. Wenz (1943, p. 1277) and Glibert (1960, p. 19) also placed it there, as did Tracey et al. (1996) and Garvie (1996, p. 87), who made Olivula a subgenus of Ancilla. Meanwhile, as noted by Palmer (1937, p. 429), Bellardi (1882) had used canalifera as the type species of his genus Ancillarina. Palmer argued that canalifera and staminea differ enough to be separated at “sectional” (i.e., subgeneric) rank, and so retained staminea in Olivula, which she treated as a subgenus of Ancilla.

In his comprehensive review of the genus Ancilla, Kilburn (1981, p. 356) treated Ancillarina as a separate genus (possibly “a sister group” of Olivula) containing “Ancilla-like species with a similarly divided fasciolar band but a total lack of callus on the spire whorls and sutures,” and represented by fossils from the Eocene of Java and possibly the Cretaceous of Burma.

Even though canalifera lacks the callused sutures characteristic of staminea, Garvie (2013, p. 60) assigned both canalifera and staminea to Ancillarina, suggesting that it be given subgeneric rank in Olivula. Garvie (2013, p. 60) also noted a change in the form of the suture callus or “collar band” over time in the three named subspecies of staminea, with punctulifera from the middle Eocene Claibornian and maternae from the lower Eocene showing “a steady decrease in the strength and sagittal angle of the [growth] lines” on the callus.

The marked callusing of the suture in staminea distinguishes it from canalifera, to which it is otherwise quite similar in overall shape, so we do not combine the two species in Ancillarina. It nevertheless seems useful to retain Olivula as a separate genus-level taxon, with a single, somewhat variable, species extending throughout much of the Gulf Coast Eocene.

The cancellate sculpture on the body whorl of O. staminea separates it from all other Coastal Plain olivoids. If, as implied by our phylogenetic analysis (Fig. 5), it is derived from Eoancilla (see Fig. 20), this would make Eoancilla paraphyletic. Further exploration of late Paleocene faunas in the Coastal Plain might further elucidate this relationship.

Olivula staminea (Conrad, 1832)
Figure 19.4–19.10

1832

Ancillaria staminea Conrad, p. 25, pl. 10, fig. 5.

1834b

Ancillaria staminea; Conrad, p. 5.

1835

Oliva staminea; Duclos, pl. 18, figs. 9, 10.

1844

Oliva staminea; Duclos, p. 11, pl. 20, figs. 9, 10.

1846

Ancillaria staminea; Conrad, p. 220.

1849

Ancillaria staminea; Lea, p. 96.

1850

Ancyllaria staminea; d'Orbigny, p. 352.

1858

Ancillaria staminea; Tuomey, p. 264.

1858

Anaulax staminea; Conrad, p. 166.

1860

Agaronia punctulifera Gabb, p. 381, pl. 67, fig. 22.

1865a

Olivula punctulifera; Conrad, p. 22.

1865a

Olivula staminea; Conrad, p. 22.

1866

Olivula staminea; Conrad, p. 17.

1866

Olivula punctulifera; Conrad, p. 17.

1883

Olivula staminea; Tryon, p. 61, pl. 3, figs. 24, 25.

1886

Ancillaria staminea; Aldrich, p. 51.

1890

Agaronia punctulifera; de Gregorio, p. 54.

1890

Ancilla (Olivula) staminea; de Gregorio, p. 57, pl. 4, figs. 5–8, 17, 18 [copied Conrad, 1832, in part].

1891

Olivula punctulifera; Heilprin, p. 398.

1893

Olivula staminea; Cossmann, p. 41.

1895b

Ancillaria staminea; Harris, p. 42.

1899a

Ancilla (Olivula) staminea; Harris, p. 30, pl. 3, fig. 13.

1899

Ancilla (Olivula) staminea; Cossmann, p. 70, pl. 3, figs. 10, 11.

1937

Ancilla staminea; Palmer, p. 428, pl. 68, figs. 7, 9, 11.

1937

Ancilla staminea maternae Palmer, p. 430, pl. 68, figs. 3, 8.

1937

Ancilla staminea punctulifera; Palmer, p. 429, pl. 68, figs. 10, 17.

1943

Ancilla (Olivula) staminea; Wenz, p. 1277, fig. 3635 [copied Cossmann, 1899].

1944

Olivula staminea; Shimer and Shrock, p. 511, pl. 210, fig. 16 [copied Conrad, 1832].

1960

Ancilla staminea; Brann and Kent, p. 44.

1960

Ancilla staminea maternae; Brann and Kent, p. 44.

1960

Ancilla staminea punctulifera; Brann and Kent, p. 44.

1960

Ancilla (Olivula) staminea punctulifera; Glibert, p. 19.

1960

Ancilla (Olivula) staminea; Glibert, p. 19.

1960

Ancilla (Olivula) staminea; Brann and Kent, p. 44.

1966

Ancilla (Olivula) staminea; Palmer and Brann, p. 492.

1966

Ancilla staminea maternae; Palmer and Brann, p. 492.

1966

Ancilla staminea punctulifera; Palmer and Brann, p. 493.

1980

Ancilla staminea punctulifera; Dockery, p. 114, pl. 176, fig. 3.

1996

Ancilla (Olivula) staminea reklawensis Garvie, p. 87, pl. 19, figs. 15, 16.

Type material

Lectotype (Palmer, 1937, p. 429) ANSP 14670; hypotypes (Palmer, 1937) PRI 3284, 3285; holotype Ancilla staminea maternae PRI 3282; holotype Agaronia punctulifera ANSP 30729; hypotype (Palmer, 1937) PRI 3283; holotype Ancilla staminea reklawensis PRI 30425; paratype PRI 30426.

Occurrence

South Carolina: middle Eocene (Bartonian), McBean Formation (Loc. SC-OR-1); Alabama: lower Eocene (Ypresian), Bashi Formation (Loc. AL-CL-2), middle Eocene (Lutetian–Bartonian), Lisbon Formation, Gosport Sand (Locs. AL-MO-2a, AL-MO-5); Mississippi: middle Eocene (Lutetian–Bartonian), Dobys Bluff Tongue, Cook Mountain Formation (Locs. MS-CL-1, MS-NE-1, MS-NE-2, MS-NE-3); Louisiana: middle Eocene (Lutetian–Bartonian), Cook Mountain Formation (Locs. LA-BI-2, LA-OU-2, LA-OU-3, LA-SA-3); Texas: middle Eocene (Ypresian–Lutetian), Stone City Beds, Reklaw Formation, Wheelock Member, Cook Mountain Formation (Locs. TX- RO-1, TX-BA-1).

Revised description

(Revised by Palmer, 1937, p. 428–429) “Nucleus consists of two and a half smooth whorls; whorls of the spire crowded, those of the apex enveloped in the lower whorls; heavy, sutural callus collar extends over the upper margin of the lower whorl and lower margin of the preceding whorl with the suture a groove along the midline of the collar; the callus has deep sagittate longitudinal lines; in most cases the sutural collar covers most of the surface of the whorls of the spire’ shell covered with coarse, longitudinal lines crossed by coarse, spiral lines which give the surface a fine, cancellated appearance.”

Other material examined

PRI 104505 (17 specimens); PRI 56421 (77 specimens).

Remarks

Olivula staminea is a distinctive, abundant, long-lived, and widespread species. From youngest to oldest, in addition to Ancilla staminea s.s. from the Bartonian Gosport Sand, it includes three named temporal subspecies: A. s. punctulifera from the Lutetian Stone City Beds and the Wheelock Member of the Cook Mountain Formation in Texas; A. s. reklawensis from the upper Ypresian Reklaw Formation of Texas; and A. s. maternae from the lower Ypresian Bashi Formation of Alabama (Fig. 20).

Our phylogenetic analysis (see below) suggests that this species may have been derived from a species of Eoancilla, perhaps E. mediavia.

Genus Palmoliva new genus

Type species

Ancillaria tenera Conrad, 1834a, by original designation herein.

Diagnosis

Spire one-third or less of total shell height. Aperture one-half to one-third total shell height. Protoconch incompletely known, but probably of 2–3 smooth whorls. Sutures callused. Spire and body whorl strongly to moderately shouldered, with shoulders bearing faint to moderate axial sculpture. Shell otherwise smooth. Olivoid band moderate to faint, weakening but persisting on dorsal side. Anterior band pronounced, with posterior margin marked by a sharp ridge. Plication plate narrow and simple. Anterior end of columella a simple point.

Etymology

Named in honor of Katherine Palmer, author of many of the taxa discussed in this paper.

Remarks

Palmer (1937) placed two similar species, Ancillaria tenera Conrad, 1834a, and Ancillaria scamba Conrad, 1832, in Bullia, but they do not belong there because, although they both have simple, pointed anterior columellar ends, they both show well-developed olivoid and anterior bands, which are not present in Bullia. These two species share pronounced shouldering on spire and body whorls and faint to moderate axial sculpture on those shoulders, features that are not present together in any other taxa discussed here. We therefore place them both in a new genus, Palmoliva.

Palmoliva scamba (Conrad, 1832) new combination
Figure 18.10–18.13

1832

Ancillaria scamba Conrad, p. 25, pl. 10, fig. 4.

1833

?Anolax plicata Lea, p. 181, pl. 6, fig. 194.

1849

?Anolax plicata; Lea, p. 96.

1854

Ancilla scamba; Conrad, p. 30.

1865a

Ancillopsis scamba; Conrad, p. 22.

1865a

Olivula ? plicata; Conrad, p. 22.

1866

Ancillopsis scamba; Conrad, p. 17.

1866

Olivula ? plicata; Conrad, p. 17.

1883

Ancillaria (Ancillopsis) scamba; Tryon, p. 61, pl. 3, fig. 26.

1890

Ancilla scamba; de Gregorio, p. 55, pl. 4, figs. 12, 13, 15, 16 [copied Conrad, 1832, in part].

1890

Ancilla (Olivula) plicata; de Gregorio, p. 57, pl. 4, fig. 9 [copied Lea, 1833, pl. 6, fig. 194].

1893

Ancillina scamba; Cossmann, p. 40.

1893

Ancillina ? plicata; Cossmann, p. 40.

1895b

?Anolax plicata; Harris, p. 35.

1901b

Ancilla (Olivula) plicata; Cossmann, p. 223.

1901b

Buccinanops (Bullia) scambum; Cossmann, p. 223, pl. 9, fig. 23 [plate captions for figs. 23 and 14 are reversed].

1937

Bullia scamba; Palmer, p. 290, pl. 44, figs. 2, 7.

1960

Bullia scamba; Brann and Kent, p. 140.

1963

Bullia scamba; Glibert, p. 98.

1966

Bullia scamba; Palmer and Brann, p. 544.

1990

“Bullia” scamba; Allmon, p. 58, pl. 9, fig. 2.

Type material

Lectotype (plus 10 specimens) (selected by Palmer, 1937, p. 291 [fide Moore 1962, p. 95]) ANSP 14647; hypotype (Palmer, 1937) PRI 3082.

Occurrence

Alabama: middle Eocene; Gosport Sand (Locs. AL-CL-1; AL-MO-2a).

Revised description

Protoconch unknown. Earliest known whorls smooth. Spire up to one-third of total height. Callus extending adapically of posterior end of aperture, giving sutures a callused form. Spire and body whorl moderately shouldered, with shoulders bearing faint to moderate axial sculpture. Posterior edge marked by ridge. Olivoid band faint and weakens but persists on dorsal side. Anterior band marked by strong growth lines, which are concave anteriorly. Posterior margin of anterior band is a sharp ridge, more pronounced in juvenile specimens. Plication plate narrow and simple. Anterior end of columella a simple point. Aperture height usually about half of total height; aperture usually about half or less of total maximum width.

Other material examined

PRI 57505 (8 specimens); PRI 57499 (2 specimens); PRI 63642 (4 specimens); PRI 104511 (3 specimens); PRI 104512 (1 specimen); PRI 104513 (3 specimens).

Remarks

Palmer (1937) noted that scamba is similar to Monoptygma lymneoides in having a similar overall shell shape and similar anterior notch and callused sutures but differs in lacking the single well-developed plication on the columella. Palmer (1937, p. 291) suggested that Anolax plicata Lea, 1833 (the lectotype of which, ANSP 5910, is lost; J. Sessa, personal communication, 11/12/21) may actually have been a juvenile of tenera.

Palmoliva tenera (Conrad, 1834) new combination
Figure 18.1–18.9

1834a

Ancillaria tenera Conrad, p. 147.

1835

Ancillaria tenera; Conrad, p. 42, pl. 16, fig. 5.

1865a

Ancillopsis tenera; Conrad, p. 22.

1866

Ancillopsis tenera; Conrad, 1866, p. 17.

1890

Ancilla tenera; de Gregorio, p. 56, pl. 4, fig. 2 [copied Conrad, 1835, pl. 16, fig. 5]

1937

Bullia tenera; Palmer, p. 291, pl. 42, figs. 7–13.

1960

Bullia tenera; Brann and Kent, p. 140.

1966

Bullia tenera; Palmer and Brann, p. 54.

1990

“Bullia” tenera; Allmon, p. 58, pl. 9, figs. 1, 3.

Figure 18. Palmoliva n. gen. (1–9) Palmoliva tenera n. comb.: (1, 2) Ancillaria tenera holotype ANSP 14646; height 29.7 mm. (3, 4) Bullia tenera hypotype PRI 3065 (from Palmer, 1937); height 23.3 mm. (5–7) Bullia tenera hypotype PRI 3064; height 26 mm; scale bar on (7) = 500 μm. (8, 9) Bullia tenera hypotype PRI 3066 (from Palmer, 1937); height 41 mm. (10–13) Palmoliva scamba n. comb.: (10, 11) Bullia scamba hypotype PRI 3082; height 35.9 mm. (12, 13) Ancillaria scamba lectotype ANSP 14647; height 36.7 mm.

Type material

Holotype ANSP 14646; hypotypes (Palmer, 1937) PRI 3064 (not “3074” as in Palmer, 1937, p. 634), 3065, 3066.

Occurrence

Alabama: middle Eocene (Bartonian), Gosport Sand (Loc. AL-MO-2a); Texas: middle Eocene (Lutetian), Stone City Beds (Loc. TX-RO-1); Louisiana: middle Eocene (PRI collection, exact localities unknown).

Revised description

Protoconch incompletely known but probably of 2–3 smooth whorls. Spire less than one-fifth of total height. Callus extending adapically of posterior end of aperture, giving sutures a callused form. Spire and body whorl strongly shouldered, with shoulders bearing faint to moderate axial sculpture. Olivoid band more marked in juveniles. Posterior edge marked by ridge, more pronounced on posterior end. Olivoid band weakens on dorsal side but persists as a broad depression with moderately deflected growth lines. Anterior band marked by strong growth lines that are concave anteriorly. Posterior margin of anterior band is a sharp ridge, more pronounced in juvenile specimens. Plication plate narrow and simple. Anterior end of columella a simple point. Aperture width at least half of total maximum width.

Remarks

The ANSP holotype is from the Gosport Sand of Alabama. PRI specimens are from older deposits to the west, including the Stone City Beds of Texas (PRI 3066) and “Louisiana. Exact data lost” (Palmer, 1937, p. 10, 292) (PRI 3064, 3065).

Palmoliva tenera n. comb. differs from P. scamba n. comb. mainly in having a lower spire, wider aperture, and more pronounced shouldering. Palmer (1937) noted that there was considerable variation in form among individuals in this species, but most of this variation appears to be ontogenetic. Younger individuals have lower spire, wider aperture, more pronounced olivoid and anterior bands, and more pronounced shoulders with stronger axial sculpture.

Genus Micrancilla Maxwell, 1992

Type species

By original designation, Amalda (Micrancilla) granum Maxwell, 1992 (Priabonian, New Zealand).

Other included species

Micrancilla alibamasiana Pacaud, Merle, and Pons, 2013 (Bartonian, Alabama); M. antipodarum Pacaud, 2014 (Lutetian, France); M. dilatata (Cossmann, 1886) (Lutetian, France); M. guanensis Pacaud, Merle, and Pons, 2013 (Ypresian, France); M. oesiensis Pacaud, Merle, and Pons, 2013 (Lutetian, France). Maxwell (1992, p. 143) stated that there are also undescribed species from New Zealand that belong to this taxon.

Original diagnosis

(Maxwell, 1992, p. 143) “Shell very small for subfamily, narrowly ovate, spire elevated, apex rather broad, well-rounded. Parietal callus thin, ascending almost vertically from top of columella then bending back sharply, running parallel to and at some distance from base of callus band on posterior portion of whorls. Suture barely hidden by callus. Aperture small, narrowly ovate, columella short, nearly vertical with a few narrow plaits.”

Micrancilla alibamasiana Pacaud, Merle, and Pons, 2013
Figure 19.1–19.3

Figure 19. Micrancilla and Olivula. (1–3) Micrancilla alibamasiana holotype MNHN.F.J13251 (from Pacaud, 2014); height 5 mm. (4–10) Olivula staminea: (4, 5) Ancillaria staminea lectotype ANSP 14670; height 31.8 mm. (6, 7) Ancilla staminea maternae holotype PRI 3282; height 25.3 mm. (8, 9) Ancilla staminea reklawensis holotype PRI 30425; height 15.4 mm. (10) Agaronia punctulifera holotype ANSP 30729; height 6.8 mm.

Type material

Holotype MNHN.F.J13251.

Occurrence

Alabama: middle Eocene (Bartonian); Gosport Sand (Locs. AL-CL-1; AL-MO-2a).

Original description

(Translation from Pacaud et al., 2013.) Small, narrow, elongated shell, cylindrical, thick test, consisting of about 5 whorls which are separated by indistinct suture lines in adulthood. The protoconch, with a pointed “button”, consists of 2 whorls. The apical angle is 35°. The spire, high, is covered by a thick callus which hides the suture on the last turn, and which extends to the adapical part of the final whorl by forming a bead. The parietal callus is thin, rising almost vertically from the top of columella and then bending sharply backwards, runs parallel, at a certain distance from the boundary of the spiral callus, and produces a narrow and unglazed spiral band on the adapical part of the spire. The callus extends over the neck, up to the fasciolar groove. The last whorl is elongated, cylindrical. The unglazed band is wide, well demarcated, strongly marked by the increments (growth lines), separated from the whorl by a clear limit of the spiral callus. The ancilline groove is well developed, narrow, linear, and deep. The ancilline band is very narrow, depressed, marked by the increases (growth lines). The neck is covered by a broad undivided fasciole. The posterior area is provided with a weak median ridge, blunt. Columellar torsion, short, slightly sinuous, not truncated and separated from the fasciole by a wide and deep fasciole groove, is decorated with 5 folds, wide and flat. The aperture, occupying a little less than half of the total height, is olivoid, contracted at its parietal angle. The siphonal notch is sinuous and widely marked. The labrum, beveled, orthoclinically oriented, is thickened in its terminal part. It presents an opisthocyrt outline in its adapical part, above the parietal angle of the opening. Exposure to UV light does not show residual colored pattern.

Remarks

This is the only species of this genus in the Americas. It is apparently rare, as we have not encountered any specimens of it in the Gosport Sand, despite intensive sampling (e.g., CoBabe and Allmon, 1994; Pietsch et al., 2016).

Discussion and conclusions

An evolutionary tree based on the cladogram in Figure 5.2 and the stratigraphic ranges shown in Figure 2 are presented in Figure 20; they suggest that the basal diversification of ancillariids in the Coastal Plain occurred in the early to middle Paleocene. There are several significant ghost ranges, suggesting that the pre-middle Eocene record is less complete than that from the middle Eocene. This species-level diversification is slightly earlier than the Eocene global diversification of olivoid and ancillariid genera (Fig. 21).

Figure 20. Evolutionary tree of the taxa discussed here, based on the cladogram in Figure 5.2 and the stratigraphic ranges in Figure 2.

Figure 21. Global diversity of genera and subgenera since the late Cretaceous of (1) Olivoidea, and (2) only Ancillariidae. Data from Table 4.

Table 4. Described genera/subgenera (n = 84) in the Superfamily Olivoidea (sensu Kantor et al., 2017). References: (1) Kilburn (1981); (2) Sepkoski (2002); (3) Kollman and Peel (1983); (4) Ninomiya (1990); (5) Ninomiya (1988); (6) Kilburn (1977); (7) this paper; (8) Kantor et al. (2017); (9) Petuch and Sargeant (1986); (10) Vermeij (1998); (11) Olsson (1956); (12) Absalão and Pimenta (2003); (13) Watters and Fleming (1972); (14) Pacaud et al. (2000); (15) Tracey et al. (1996); (16) Pacaud et al. (2013); (17) Kantor and Bouchet (2007); (18) Klappenbach (1962); (19) Petuch (1988); (20) Drez (1981); (21) Voskuil (2018).

Olivoids appear to have originated in the Cretaceous in the eastern Tethys, the region that now includes Madagascar, South Asia, and Japan, and soon spread to the Gulf Coast of North America and western Europe. These early olivoids were stem group ancillariids. The genus Micrancilla appears to have been part of this basal ancillariid radiation, perhaps originating in western Europe and spreading to New Zealand and America (Pacaud et al., 2013; Pacaud, 2014). This biogeographic history may explain the absence of Micrancilla in the Coastal Plain prior to the late middle Eocene.

The relative stratigraphic position of the four species of Eoancilla is consistent with them comprising a single ancestor-descendant lineage, perhaps including the ancestors of both Olivula staminea and all of the other species considered here.

The genus Agaronia, as presented here, is paraphyletic, and includes the ancestry of the oldest known species of the genus Oliva. Agaronia is widely distributed beyond the Coastal Plain up to the Recent; its comprehensive phylogenetic analysis is beyond the scope of this paper, so we have not subdivided it at the genus level.

Most of the species treated here have durations of <10 my (7 of 19 are known from a single formation), but three species are relatively long-lived (Anbullina elliptica, ca. 20–23 my; Ancillopsis altilis, ca. 20 my; Olivula staminea, ca. 18 my), and all three appear to show noticeable anagenetic change through these durations.

The Paleogene gastropods of the Coastal Plain are relatively well studied, but our analysis indicates that a significant number of taxonomic assignments should be changed. Nine of the 19 Coastal Plain species listed in Table 1 are here assigned to different genera and nine to different families than they were in the most recent authoritative summary more than 50 years ago (Palmer and Brann, 1966).