Colonial metazoans that lived symbiotically with hermit-crabs create striking and distinctive fossils. Examples of such fossils recorded (Schindler and Portell, 1993) from Cenozoic deposits in Florida include the scleractinian coral Septastrea marylandica (Conrad, 1841) (see Darrell and Taylor, 1989), the hydrozoan Cystactinia ocalana Brooks, 1964, and the bryozoan Hippoporidra edax (Busk, 1859) [recorded as H. calcarea (Smitt) by Scolaro, 1970]. In all of these fossils, the symbiotic colony covers the entire external surface of a gastropod shell with a thick encrustation. Growth of the colony outwards from the shell aperture in the form of a helicospiral tube greatly extends the size of the chamber available for the hermit-crab occupant. In no known fossil examples of symbioses are the hermit-crabs preserved in situ. However, modern analogues, along with functional morphological considerations, provide good criteria for inferring that this peculiar colonial growth pattern occurred in response to the presence of a symbiotic hermit-crab, at least for examples within the Lower Jurassic-Recent range known for fossil hermit-crabs (see Walker, 1992; Taylor, 1994).

A rare occcurrence of what is believed to be a quasillitacean ostracode has been found in Ohio. The occurrence of the family Quasillitidae in the Pennsylvanian was questioned by Sohn and Stover (1961, p. Q374). This included the genera Quasillites Coryell and Malkin, 1936, and Graphiadactyllis Roth, 1929. The latter genus is common in Chesterian strata in the United States. Recently a single occurrence of a new genus and species, Simulatus adornatus, has been found in Pennsylvanian (Desmoinesian) strata.

Examples of the “hydrozoan” Radiotrabeculopora reticulata Fan, Rigby, and Zhang, 1991 have been recently recovered from Lower Permian rocks in the Inyo Mountains, Owens Valley area, of east-central California by G. Linder and C. Stevens. That genus and species were originally described from the Middle Permian (Leonardian-Lower Guadalupian) Maokou Formation from western Hubei, China, by Fan et al. (1991). This the first report of the genus and species from North America.

The lower Cretaceous strata of the Neuquén Basin of Argentina are richly fossiliferous and characterized by diverse, primarily normal marine, molluscan-dominated faunas containing many interesting taxa. Among these, in the Lower Hauterivian part of the Agrio Formation at Cerro Mesa (Fig. 1), are diverse, coarsely ornate trigoniid bivalves of the genus Steinmanella Crickmay, 1930, and a new genus and species of ornate Mytilidae (Nodomytilus trigonimimus). The new taxon appears to be convergent in its surface sculpture on the Austral Gondwanian trigoniid Steinmanella transitoria (Steinmann, 1881). This may represent a rare case of convergence, or even mimicry, in the fossil record. The trigoniids have relatively low predation levels among bivalves (Kauffman, personal observation on fossil and recent populations). Convergence on the trigoniid morphotype could have been an adaptive advantage to frequently predated Mytilidae. The new taxon is described herein and compared to co-occurring Steinmanella.

Gastropods belonging to the extinct family Cirridae Cossmann, 1916 are relatively rare elements of Mesozoic marine communities. The unusual change in shell coiling from dextral to sinistral during their ontogeny represents a character which makes their recognition in the fossil record easy. This shell feature is also known from members of the Paleozoic family Porcelliidae Koken in Zittel, 1895, uniting the planispirally coiled Porcelliinae with the sinistrally coiled Agnesiinae Knight, 1956. This heterostrophy is not homologous with that of the Heterobranchia (Frýda and Blodgett, 2001). Shells of Porcelliinae and Agnesiinae bear an apertural slit, in contrast to the Mesozoic Cirridae. According to Bandel (1993a), slit-bearing members of the Porcelliidae evolved into the Cirridae without slit during the Triassic. Therefore Bandel (1993a) united both families into one natural group, the Cirroidea. That name has now been changed into Porcellioidea, according to the older family name (see discussion in Bandel and Frýda, in press). The oldest representatives of the Porcelliidae were reported from Silurian strata (Frýda, 1997). The youngest Cirridae are known from Late Cretaceous strata (Kiel and Bandel, 2002). Frýda and Blodgett (1998) described an Emsian (Early Devonian) porcellioid—Alaskacirrus bandeli—without slit as in the Mesozoic Cirridea, and pointed out that phylogenetic relationships of the Paleozoic Porcelliidae and Mesozoic Cirridae are still uncertain. The placement of the Porcellioidea within the Archaeogastropoda is based on the discovery of an archaeogastropod-type protoconch in the Paleozoic Porcelliidae (Yoo, 1994) as well as in the Mesozoic Cirridae (Bandel, 1993a). In addition, Bandel (1993a) mentioned the presence of a nacreous inner layer in a Mesozoic cirrid. This observation was from an unpublished master's thesis (Hänsel, 1992) supervised by him. Hänsel (1992) demonstrated that nacre is present in shells of the Late Cretaceous cirrid Sensuitrochus ferreri Quintero and Revilla, 1966 (Fig. 1.1), using peels of polished and etched shells to determine the shell structure. Although this observation is important for the interpretation of the higher taxonomic position of the Cirridae, it was never published. The aim of the present study is to document the presence of nacreous shell in the Mesozoic cirrid Sensuitrochus ferreri, using scanning electron microscopy.

The bivalves of early late Anisian (Middle Triassic) age from Leidapo (also Bangtoupo) in the northeastern vicinity of Qingyan in the south-central part of Guizhou Province, southwestern China (Fig. 1), are highly diverse and fairly well studied (e.g., Chen et al., 1974; Yin, 1974; Nanjing Institute of Geology and Palaeontology, 1976; Gan and Yin, 1978; also Stiller, 2001). The study of these Anisian fossil assemblages began with Koken (1900) and Hsu and Chen (1943). The renewed study of this site and its fossil assemblages by Stiller (1997, 2001) and Chen et al. (2001) yielded a bivalve taxon with unusual and, for an early Mesozoic species, unexpected hinge features. The new taxon is fairly common at Leidapo/Bangtoupo; nevertheless it was only recently recognized (Stiller, 2001) and has not heretofore been described.

The earwigs comprise an order (Dermaptera) of polyneopterous insects allied to the Dictyoptera and Grylloblattodea (Giles, 1963; Hennig, 1969; Boudreaux, 1979). Dermaptera have at times in the past been allied with the Phasmida, Embiodea, and Plecoptera (e.g., Blacklith and Blacklith, 1968; Jamieson, 1987) but these relationships do not seem to be congruent with the overall body of data for Polyneoptera phylogeny and the monophyly of a Grylloblattodea + Dermaptera + Dictyoptera clade currently has perhaps more evidence than competing hypotheses (e.g., Carpenter and Wheeler, 1999; Wheeler et al., 2001). However, revised morphological and paleontological evidence may suggest that Dermaptera are basal within Anartioptera—a clade consisting of Plecopterida, Orthopterida, Grylloblattodea, and Mantophasmatodea, as well as the earwigs (e.g., Engel and Grimaldi, 2004). The earwigs are certainly autapomorphic, like many polyneopterous insects, and their definitive placement remains elusive.

New millipede specimens from the Paleozoic of Scotland are described, including Archidesmus macnicoli Peach, 1882, from the Lower Devonian (Lochkovian) Tillywhandland Quarry SSSI and three new taxa—Albadesmus almondi, Pneumodesmus newmani, and Cowiedesmus eroticopodus—from the mid Silurian (late Wenlock—early Ludlow) Cowie Formation at Cowie Harbour. Cowiedesmus eroticopodus new species is placed within the new Cowiedesmidae within the new order Cowiedesmida. Kampecaris tuberculata Brade-Birks from the Lower Devonian (Siegenian) of the Lanark Basin near Dunure is shown not to be a kampecarid myriapod, redescribed as Palaeodesmus tuberculata and placed order incertae sedis within Archipolypoda. Anthracodesmus macconochiei Peach is also redescribed and tentatively placed order incertae sedis within Archipolypoda. Archidesmus macnicoli, Albadesmus almondi, and Palaeodesmus tuberculata are each demonstrated to have broad sternites with laterally placed coxal sockets and paramedian pores containing paired valves. These pores are interpreted as having housed eversible vesicles. Some specimens of Archidesmus macnicoli and Cowiedesmus eroticopodus are male and have a pair of modified legs on trunk segment 8, identified as leg pairs 10 and 11, respectively. The presence of modified anterior legs restricted to segment 8 increases the range of variability known in modified appendage location in male millipedes and compounds existing uncertainty about using the presence of gonopods on trunk segment 7 as a synapomorphy of Helminthomorpha. An affinity between Archidesmida and Cowiedesmida is suggested based on possession of modified legs on segment 8 and Archidesmida + Cowiedesmida is placed along with Euphoberiida in Archipolypoda based on possession of free, broad sternites with bivalved paramedian pores and fused pleurotergites. The oldest known evidence of spiracles is demonstrated in Pneumodesmus newmani, proving that the oldest known millipedes were fully terrestrial.

The stephanid wasps are of great phylogenetic and biological significance among parasitic Hymenoptera, itself one of the major radiations of insects and of critical ecological and agricultural importance. The family, the only one of its superfamily (e.g., Gauld and Bolton, 1988; Goulet and Huber, 1993: although Rasnitsyn, 1988, 2000 includes the traditional Trigonalyoidea, Megalyroidea, Ceraphronoidea, and some extinct lineages in the Stephanoidea), is hypothesized by some authors to be basal within the diverse parasitoid lineage Apocrita (Rasnitsyn, 1975, 2000; Königsmann, 1978; Rohdendorf and Rasnitsyn, 1980; Whitfield, 1992, 1998; Vilhelmsen, 1996, 2001). Such a phylogenetic placement makes the stephanids an interesting link between the principally xylophagous wood wasps (i.e., the paraphyletic suborder Symphyta), the sole parasitic symphytan family Orussidae, and the remainder of the Apocrita (Orussidae + Apocrita = Euhymenoptera). Thus, stephanids may represent one of the earliest families of parasitoid wasps exhibiting the characteristic “wasp waist,” allowing for more control and flexibility during oviposition. Tantalizingly, the stephanids are morphologically similar to orussids in that both exhibit a characteristic series of tubercles on the head (presumably an adaptation for allowing them to move through burrows in wood after eclosion). These similarities, however, may be convergent adaptations of parasitizing wood-boring insects (a plesiomorphic biological trait across the Apocrita) and stephanids may belong to a clade of evaniomorphous wasps, albeit still relatively basal within that lineage (e.g., Rasnitsyn, 1988; Ronquist et al., 1999). In either case, Stephanidae figure prominently in cladistic studies of the Hymenoptera and are of presumably ancient origin based on their phylogenetic position (e.g., Rasnitsyn, 2000). Fossils of the family, however, are rare and until now have been restricted to Tertiary deposits.

The specimen studied here represents the first fossil Euzygoptera Bechly, 1996 described in South America. The lack of fossil damselflies from this subcontinent is probably an artifact related to the scarcity of fossil insect collections. Differences in the world fossil record of these insects (as many others) could be correlated to the level of activity of researchers in the different continents. Thus the fossil Lestinoidea Calvert, 1901 (sensu Bechly, 1996) are mainly known from Europe (Nel and Paicheler, 1994) where a long history of paleoentomology (and paleontology of Odonata) took place. From North America there is only one record in the Eocene of the USA (Cockerell, 1940), despite an ancient and long activity in this field. From Asia the group is known from the Oligo-Miocene of Turkey (Nel and Paicheler, 1994) and from the Miocene of Japan (Fujiyama, 1985). What does not fit in this hypothesis is the curious lack of records from Asia, despite the high number of paleoentomologists of the Russian school. The possible explanation of this could be that Russian researchers have preferred historically to study Paleozoic and Mesozoic rather than Cenozoic insects. Thus, due to the recent increasing number of paleoentomologists, new discoveries similar to the present one shall probably modify the present fragmentary fossil record of Lestinoidea.

A Lower Pennsylvanian (Morrowan) silicified ostracode fauna occurs just above the conformable Mississippian-Pennsylvanian boundary within the Barnett Formation in Texas. The fauna contains several taxa that were previously restricted to the Upper Mississippian and numerous taxa only known from the Lower Pennsylvanian. New taxa proposed include Amphissites (Amphissites) morrowanensis n. sp., Polytylites subrectus n. sp., Kirkbyella (Berdanella) delicata n. sp., Kindlella proscillata n. sp., Libumella walkerorum n. sp., Moorites tumidus n. sp., Leptoderos arytaina n. gen. and sp., and Cribroconcha prolixa n. sp.

The fossil site known as Lothagam lies west of the southern end of Lake Turkana (formerly Lake Rudolf) in northern Kenya. The Turkana Basin is famous for its paleontological, paleoanthropological, and archeological records from both east and west of this large lake in the eastern part of the rift system. The Plio-Pleistocene outcrops have been the focus of important research in early hominid taxonomy and evolution, subsistence behavior of early hominids, the tempo and mode of evolution in lacustrine gastropods, vertebrate taphonomy, and mammalian faunal turnover, as well as basic systematic paleontology of terrestrial and aquatic vertebrates. Lothagam is a more restricted area (~60 km2 of outcrop) and its strata are older—late Miocene to early Pliocene, overlain unconformably by Quaternary sands, gravels, and coquinas. Only a handful of African sites document this time period that includes the Messinian salinity crisis and major floral and faunal changes in many parts of the world. Thus, this monograph is a welcome publication for those who work on the later Neogene, and for paleoanthropologists interested in the ecological context of basal hominids.

Kues and Batten (2001, p. 30, fig. 6.17–6.20) described several distinctive, minute, low-spired gastropod specimens from the Desmoinesian (Middle Pennsylvanian) Flechado Formation of north-central New Mexico, assigning them questionably to Lunulazona Sadlick and Nielsen, 1963 because of the strongly developed collabral elements similar to those of that genus. These shells, consisting of three or four inflated whorls, are at most 1 mm in height and the later whorls bear conspicuous, sharp, widely spaced collabral ribs that bend strongly across a wide, slightly flattened band interpreted as a peripheral selenizone. While recognizing these specimens as a distinct, unnamed taxon, Kues and Batten (2001) believed that they likely represent juveniles of an as yet unrecognized larger species of gastropod with a different mature morphology.

Studies of larval development in the calyptraeid gastropod genus Crepidula Lamarck, 1799 have greatly enhanced the ability of systematists to delineate the Recent species in this challenging group. Although the simple, limpetlike growth form and near absence of surface ornamentation in adult Crepidula provide few diagnostic characters, larval developmental strategies (i.e., feeding or planktotrophic vs. nonfeeding or lecithotrophic larvae) appear to be stable within species and evolve rapidly, making them useful taxonomic tools. Molecular phylogenetic analyses of several species previously believed to possess multiple developmental modes—a condition known as poecilogony—found that these “species” are instead clades comprised of multiple cryptic species distinguishable only by larval type (e.g., Gallardo, 1977, 1979; Hoagland, 1977, 1984, 1986; Collin, 2000a, 2001).

Protostegids are Cretaceous marine turtles. Fossil materials assignable to the family Protostegidae range from early Albian to Late Campanian in age and have been described from all continents except Antarctica (Hirayama, 1995). The group includes two gigantic forms, Archelon Wieland and Protostega Cope, that reached maximum carapace lengths in excess of 2 m and rank among the largest turtles that ever lived.

In this paper, we describe two specimens of Protostega gigas Cope housed in the Field Museum of Natural History (FMNH), Chicago, Illinois: FMNH P27452 and FMNH PR58. Both are from the Mooreville Chalk (Upper Santonian to Lower Campanian: Mancini et al., 1995) in Greene County, Alabama, and are noteworthy because they show tooth marks from at least one large shark. One of the specimens also exhibits five embedded teeth of the Late Cretaceous cretoxyrhinid shark Cretoxyrhina mantelli (Agassiz). This note constitutes the first report of protostegid turtles bitten by C. mantelli.

As a scientist who works on the Cretaceous–Tertiary boundary for something less than an assistant professor's salary, I eagerly awaited the arrival of this volume at my university library. Apparently I wasn't the only one. Because although I was ready to pounce and present my card the moment it arrived, the librarian reported The Hell Creek Formation and the Cretaceous–Tertiary Boundary in the Northern Great Plains stolen before I got there.