Well-preserved Ordovician conodonts are described from a micritic limestone sequence exposed in the Satun area of southern peninsular Thailand. the faunas represented by these conodonts have North Atlantic Realm affinities and are identical to those reported from North Atlantic Middle to Upper Ordovician successions. Representative conodonts of some of these faunas have also been reported from South China. in ascending order, three conodont zones are discriminated in the Satun sequence: the Pygodus anserinus range Zone, the Baltoniodus sp. cf. B. variabilis range Zone, and the Hamarodus europaeus range Zone. Strata between the B. sp. cf. B. variabilis and H. europaeus zones are not zoned. the conodont-bearing limestone is thought to have been deposited on the continental margin of northeastern Gondwana. Sixteen species belonging to 12 conodont genera, and two unidentified coniform elements, are systematically investigated.

The Chattanooga Shale of the southern Appalachian Basin contains a diverse conodont fauna of the high Givetian, Frasnian, and Famennian. The predominantly fine-grained strata were deposited in an offshore setting where depositional packages are separated by unconformities. Conodonts allow regional and global correlation of these strata, recognition of the Frasnian-Famennian boundary, and narrow biostratigraphic constraint of two Frasnian ash beds, MN Zone 8 for the Belpre Ash and upper MN Zone 13 for the Center Hill Ash. Three new Frasnian palmatolepid conodonts are described in open nomenclature, and the holotype of Palmatolepis regularis Cooper is reillustrated.

The skeleton of a newly discovered, exceptionally preserved specimen of Saniwa ensidens is described in detail. the fossil consists of a complete articulated skeleton exposed in dorsal view. It adds important additional information to our knowledge of the anatomy of this fossil varanoid taxon, including a detailed description of the dermatocranium in dorsal view, complete vertebral counts, and a detailed account of the appendicular skeleton. Cartilage preservation allows the identification of treacheal rings, sternum, inscriptional ribs, epicoracoid and suprascapula. Patches of skin are preserved on dermal skull bones, and scattered scales surround the entire skeleton. Incomplete ossification of carpal and tarsal elements, as well as of epiphyses, indicate that the specimen is not fully mature.

Epipunctae, a new type of shell perforation, are well developed in typical taxa of the family Plaesiomyidae, a group of common orthide brachiopods from Laurentia and some other tropically located tectonic plates of Late Ordovician age. These minute, prominently elongate, tubular structures are similar to endopunctae in size and density, but differ in being oblique, intersecting the shell surface at a relatively low angle, and being confined largely to the outer portion of the shell wall. the tubules are similar in orientation to aditicules within the same shells but are much smaller and denser, usually aligned along fine growth lines and arranged in crude longitudinal columns. Exceptionally preserved phosphatic molds of bundled setal canals inside epipunctae and aditicules, described for the first time in this paper, are direct evidence that these two types of tubular structures of different sizes had the same function of housing sensory setae along the shell margin, but both the setae and the tubules became abandoned in the outer portion of the shell wall through burial by the secondary shell layer when the shell margin migrated forward. Epipunctae have been found so far only in plaesiomyid shells, but aditicules are common in many groups of the order Orthida. the taxonomic value of epipunctae is shown by a reassessment of Pionorthis Schuchert and Cooper, 1932. the hypotype previously regarded widely, but erroneously, as the archetype of ‘Orthis sola’ Billings, 1866, the type species of Pionorthis, is allied to Plaesiomys Hall and Clarke, 1892. It bears the characteristic epipunctae. the holotype of Orthis sola is a dalmanelloid shell with true punctae, assignable to Mendacella Cooper, 1930. This warrants rejection of the genus Pionorthis.

The morphology of Tuzoia is reinterpreted in the light of abundant new specimens from the Middle Cambrian Burgess Shale (British Columbia, Canada) and Kaili (Guizhou, China) Lagerstätten. Tuzoia was a very large (up to 180 mm long) bivalved arthropod with a nonmineralized domelike carapace strengthened by prominent pointed features and often flanked by a lateral ridge bearing a spiny frill. The reticulate pattern of Tuzoia is comparable with that of present-day crustaceans (e.g., myodocope ostracods) and is interpreted as a structural compromise between exoskeletal lightness and high resistance to mechanical stress. Tuzoia had a pair of large, stalked, spherical, possibly compound eyes facing forward. Flagella-like antennae protruded through the anterior notch. No other appendages are known except possible filamentous setae underlying the carapace. Tuzoia typically occurs as laterally (lc) or dorsoventrally (dvc) compacted carapaces or single valves. Each type (lc or dvc) emphasizes particular aspects of the morphology (e.g., spiny lateral ridge, ventral margin) that were often interpreted as specific differences by previous authors. A revision of Tuzoia validates only 7 of the 23 named species. Tuzoia is placed tentatively within a group of large bivalved arthropods along with Isoxys and the possible ancestors of Thylacocephala (Lower Cambrian–Upper Cretaceous). In the Middle Cambrian, Tuzoia occurs across Laurentia, South and North China, and the Perigondwanan area (Bohemia) within a relatively narrow subtropical belt, indicating a high dispersal capability and possible latitudinal control on its distribution. Functional morphology, taphonomy, and the distributional pattern indicate that Tuzoia was a free-swimming arthropod.

The Lower Cambrian brachiopod Heliomedusa orienta Sun and Hou, 1987a, first identified as a jellyfish, was later described as a craniopsoid brachiopod. A new sample of 1,150 individuals of this brachiopod, measuring 3.1–22.0 mm long, from two new sites of the Lower Cambrian Yuanshan Formation was examined. the sample includes several with exceptional preservation of nonmineralized skeletons that reveal previously unknown features and fill a gap in our knowledge of the detailed anatomy of fossil discinids. It is here reinterpreted as a discinid brachiopod on the basis of its many distinctive, discinid anatomical features, such as a longitudinally oval pedicle foramen in the anterior region of the posterior sector of the ventral valve; inferred, short, but large pedicle descending ventrally from the ventral valve; inferred, paired rectus muscles in the large pedicle canal; elongate scars of paired anterior adductors; and a median septum connected to a U-shaped ridge on the ventral interior. the two growing zones of its exceptionally preserved, unique lophophore extend posteriorly instead of anteriorly as in all Recent inarticulate brachiopods. Its recognition as the first and earliest discinoidean extends its stratigraphic range from the Ordovician to the Lower Cambrian. This reassignment implies that the organophosphatic, pediculate lingulids and discinids evolved before the carbonate, nonpediculate craniopsids and craniids. Its occurrence at chronological proximity to the Cambrian explosion of small metazoans sheds light on the early morphological diversification and the adaptive radiation of the Lower Cambrian brachiopods into the available niches.

The Upper Dharmaram Formation (Lower Jurassic, Sinemurian) of India has yielded three sauropodomorph dinosaurs, two new taxa and an indeterminate one. Lamplughsaura dharmaramensis n. gen. and sp., represented by several partial skeletons, is a heavily built quadrupedal form (body length ~10 m). Autapomorphies include teeth with strongly emarginated distal edge; caudal cervical neural spines bearing a vertically oriented ligamentous furrow on cranial and caudal surfaces and a transversely expanded spine table; caudal neural spines bearing a craniodorsally directed spur (proximal caudal vertebrae) or a large process (midcaudal vertebrae); caudal neural spines shorter than transverse processes so former lost first in passing along tail; and a plesiomorphy that is the nontrenchant form of manual ungual I. The Indian dinosaurs were coded for two recent datamatrices for basal sauropodomorphs. The results of this preliminary analysis indicate that Lamplughsaura is either a basal Sauropoda or, less likely, based on Templeton's test, a stem sauropodomorph. The second large form, represented by the proximal half of a femur, is a sauropodomorph that is more derived than Saturnalia (Brazil) and Thecodontosaurus (Great Britain) from the Upper Triassic. This is also true for the smaller (body length ~4 m as adult) Pradhania gracilis n. gen. and sp. which lies outside of the Sauropoda + Plateosauria clade, so it is definitely a stem sauropodomorph. Pradhania is known from fragmentary material; an autapomorphy is the very prominent medial longitudinal ridge on the maxilla.

Biostratigraphically significant finds of two important species of Nemagraptus in the Middle and Upper Ordovician carbonate sections of Baltoscandia are reviewed. Nemagraptus subtilis is found in the lower part of the Uhaku Regional Stage, which is correlated with the Hustedograptus teretiusculus graptolite zone. Nemagraptus gracilis is restricted to the upper part of the Kukruse Stage in the Central and South Estonian and western Latvian sections. This level correlates with the Nemagraptus gracilis graptolite Zone. the vertical distribution of these taxa is similar to, although less complete than, their ranges in the classic black shale succession in Scania, southern Sweden. the first three-dimensionally preserved specimens of N. subtilis are illustrated and described. Nemagraptus subtilis can be differentiated from N. gracilis by its lack of cladial branches, more slender stipes, shorter sicula, and upward orientation of the first two thecae.

The Tribes Hill Formation (upper Skullrockian) of New York records the earliest Ordovician diversification of cephalopods, in particular ellesmerocerids, on the east Laurentian, shallow carbonate platform. Revision of this cephalopod fauna on the basis of approximately 430 specimens collected across eastern New York has led to new information on inter- and intraspecific variation of the taxa and extensive synonymization of species-level taxa. The Ellesmeroceratidae and Protocycloceratidae, Ellesmeroceras, and Eremoceras are emended, Eorudolfoceras n. gen. and Dakeoceras champlainense n. sp. are erected. A rank abundance plot of the 342 specimens at a locality in the Lake Champlain lowlands provides information on the community structure of the nautiloid fauna, where small orthoconic taxa are shown to dominate strongly. The small orthocone Ectenolites was the most common genus in terms of total occurrences, was the most paleogeographically widespread genus, and was the only genus to cross the Cambrian-Ordovician boundary.

New rhynchonelliformean brachiopods are documented from Upper Cambrian and Tremadoc beds of the Cordillera Oriental and Puna regions, which are representative of the initial radiation of Plectorthoidea on the Andean (South American) shelves of Gondwana. Protorthisina n. gen., so far the oldest known representative of the family Euorthisinidae, and Lesserorthis n. gen. (Euorthisinidae?) are described, as well as the new species Euorthisina? nazarenensis, Kvania mergli, Kvania lariensis, Kvania azulpampensis (with two subspecies), Kvania? primigenia, and Nanorthis calderensis (with two subspecies). Protorthisina, Kvania, and Nanorthis form a stratigraphically continuous series of species displaying well-defined evolutionary trends involving size, shell ornament, and internal features. in the cardinalia, a transition from a V-shaped septalium (typical of Protorthisina) through almost parallel brachiophore plates (typical of Kvania) to the orthoid notothyrial platform of Nanorthis is documented. the species Nanorthis purmamarcaensis Benedetto and “Nanorthis” grandis (Harrington) are considered as the end members of the lineage. the heterochronic (peramorphic) origin of this trend is supported by ontogenetic evidence from species of Kvania and Nanorthis calderensis. the origin of the ‘plectorthoid’ cardinalia of Kvania from a euorthisinid configuration present in the stem group, followed by the appearance of a orthoidlike configuration in Nanorthis, pose an intricate systematic problem. the preliminary phylogenetic analysis of the northwestern basin taxa shows that the Upper Cambrian Protorthisina simplex n. gen. and sp. is the stem group of both the nanorthid and euorthisinid clades. On the basis of the new evidence, the genus Nanorthis is removed from the Orthoidea to the Plectorthoidea, and the diagnosis of the families Euorthisinidae and Nanorthidae are revised.

An abundant and diverse Late Griesbachian (Early Induan) Wordieoceras-dominated cephalopod fauna occurs in the lower part of the Daye Formation at the Wenjiangsi section, Guiding County, Guizhou Province, South China. The cephalopod fauna consists of 17 species belonging to 10 genera, including two nautiloid species and 15 ammonoid species representing the families Ophiceratidae, Proptychitidae, Meekoceratidae, and Khangsariidae. One genus and five species are new: Vishnuites wenjiangsiensis, Pseudovishnuites guidingensis, Wordieoceras guizhouensis, Gyrophiceras subplicatum, and Hubeitoceras? Wangi.

A new species of the Montastraea “annularis” species complex is herein described from Pleistocene coral reefs of the Caribbean Sea. The species, Montastraea nancyi n. sp., had a broad geographic distribution at mainly insular sites 125 Ka. It has a fossil record extending from >600 Ka (thousand years) to 82 Ka, both first and last occurrences exclusively on the island of Barbados. It also had a broad environmental tolerance, occurring in fringing, windward back-reef and reef-crest, leeward reef-crest, and lagoonal patch-reef environments. In every habitat in which it lived, there are examples that it either dominated the coral fauna or shared dominance with Acropora palmata, a dominant shallow water coral in high-energy Pleistocene and modern reefs. The extinction of Montastraea nancyi resulted in evolutionary and ecological change in surviving members of the M. “annularis” species complex.

The recovery of well-preserved silicified immature exuviae allows the first description of the early ontogeny of the phacopid Nephranops incisus incisus from the lower Famennian of Thuringia (central Germany). Evidence is presented that both planktonic and benthic protaspid larval stages were present in phacopid trilobites. Ontogenetic meraspid changes of this species are similar to those of Weyerites and Phacops, supporting the close phyletic relationships between these genera and the ontogenetic homogeneity of the Phacopidae.

A small faunule of silicified hexactinellid sponges and root tufts has been recovered from the upper Guadalupian Reef Trail Member of the Bell Canyon Formation, from the Patterson Hills, in the southwestern part of the Guadalupe Mountains National Park in western Texas. Some demosponges from the type section of the Reef Trail Member, near the mouth of McKittrick Canyon on the front of the Guadalupe Mountains in the park, have also been documented. Included in the faunule from the Patterson Hills localities are the new amphidiscosid hexactinellid pelicasponge Trailospongia reischi n. gen. and sp., the questionable pelicaspongiid Hexirregularia nana n. gen. and sp., and the dictyospongiid hexactinellids Microstaura doliolum Finks, 1960, and Microstaurella minima n. gen. and sp., and Microstaurella parva n. gen. and sp. They are associated with specimens of the lyssacinosid brachiosponges Toomeyospongiella gigantia Rigby and Bell, 2005, Toomeyospongia modica n. sp., and Toomeyospongia minuta n. gen. and sp., and fragments of three different types of root tufts, termed Tufts 1, 3, and 4. Two specimens of the new cylindrical demosponge Mckittrickella pratti n. gen. and sp. are associated with Tuft 2 in the collection from the type section of the Reef Trail Member, and a third specimen was collected from the member in the Patterson Hills. These sponges from Localities 1-7 are the youngest Permian sponges known from the region, and possibly from North America.

The Arco Hills Formation contains abundant lingulate, strophomenate, and rhynchonellate brachiopods, echinoderms, corals, bryozoans, and rare vertebrate and trilobite fossil fragments. Fossils are equally abundant in carbonate and siliciclastic units; however, silicified brachiopods are limited to carbonate lithologies which occasionally have minor amounts of siliciclastic sediment. These silicified brachiopods were extracted for taxonomic, taphonomic, and paleoecologic description. Chesterian brachiopod assemblages of the Cordilleran region are poorly described and this work represents the only systematic treatment of Chesterian macrofossil assemblages in Idaho. Fifteen genera (23 species) of brachiopods are presented from Arco Hills Formation, including two new species: Anthracospirifer arcoensis and Composita idahoensis, described herein.

Giant Middle Coniacian to Lower Campanian Platyceramus Seitz is among the largest Cretaceous bivalves, commonly reaching an axial length of over 1 m, and occasionally over 2–3 m in size. the genus is characterized by its large size, very low convexity, normal inflation limited mostly to the umbonal area, and flattened flanks. It is especially common in moderately deep calcareous shale facies, as well as in chalks and limestones of the Niobrara Formation and equivalents. Preferred facies contain abundant pyrite, elevated total organic carbon (TOC), and very low biotic diversity. the genus maintains its giant size in these facies, and becomes more abundant. It clearly prefers dysoxic facies. As such, it probably is chemosymbiotic; photosymbiosis is almost ruled out because of inferred water depths of 200–350 m. It is also found more sparsely, and of smaller size, in oxygenated facies, including shoreface sandstone. the study area contains over 81 giant-sized Platyceramus platinus (Logan, 1898) on a single bedding plane; there are very few small ones. This allows spacing, orientation, and size analysis to be performed on an adult population.

A new monospecific family of asteroids (Echinodermata) is based on Eukrinaster ibexensis n. gen. and sp. from the Lower Ordovician of Utah and Nevada. Eukrinaster, Arenig in age, is one of the earliest of known asterozoans. The new, relatively well-preserved fossils yield important information on character state distribution that will be useful for the interpretation of phylogenetic relationships among the three asterozoan classes, the Somasteroidea, Ophiufoidea, and Asteroidea. In addition, overall form is suggestive of certain living asteroids: to the extent that form equates with function, similarities suggest ecologic parallels in these only distantly related asteroids inhabiting ecologically distinct worlds.

Study of abundant well-preserved specimens of cyrtospiriferid brachiopods from early Famennian triangularis Zone shelf deposits from South China shows that none of them can be attributed to the genera Cyrtospirifer Nalivkin in Fredericks, 1924, or Tenticospirifer Tien, 1938, as previously assigned. Some of these forms are reassigned to the new genus Plicapustula, with Spirifer (Sinospirifer) gortanioides Grabau, 1931 serving as the type species. Restudy of the Upper Devonian cyrtospiriferids of North America and South China indicates that genera of the subfamily Cyrtospiriferinae all developed a delthyrial covering usually composed of two or more thin plates referred to as a composite pseudodeltidium. the delthyrial covering of Cyrtiopsis Grabau, 1923 and other genera of the subfamily Cyrtiopsinae is a convex pseudodeltidium. the lack of a pedicle foramen penetrating the pseudodeltidia of Frasnian Cyrtospirifer indicates that most species had an atrophied pedicle. the pseudodeltidia of most early Famennian cyrtospiriferids are perforated by a pedicle tube or a central hypothyrid foramen as in Sinospirifer Grabau, 1931, or a hypothyrid-to-submesothyrid foramen as in Lamarckispirifer Gatinaud, 1949 and Plicapustula n. gen. the orientation and concavity of the interarea, used with other shell characteristics, are useful characters in species-level taxonomy of Famennian cyrtospiriferids.

Four major types of radial micro-ornament characterize Late Devonian species of Cyrtospirifer and other genera of the Cyrtospiriferinae. These are 1) the verneuili type, consisting of microspines arising from the shell surface with spine bases extending into the primary shell layer, with radial capillae; 2) the whitneyi-subextensus type with small pustules both in the grooves and on the plications; 3) the subarchiaci type characterized by pustules only on plications; and 4) the hayasakai type with coarse elongated pustules on plications and capillae in grooves. There is a notable increase in complexity of the medial plication patterns of shells of Late Devonian cyrtospiriferinids. Simple sinal plication patterns characterize shells of Frasnian species of Cyrtospirifer and related genera, whereas most early Famennian cyrtospiriferinids developed complex patterns. We have documented three variations in the structure of the cardinal processes of the Late Devonian cyrtospiriferids. These consist of 1) unsupported; 2) supported by callus (secondary shell material) from below; or 3) supported by a median septum.

In Hunan-South China, cyrtospiriferid diversity was low in the late Frasnian, but a postextinction radiation of cyrtospiriferids in the very early Famennian resulted in the evolution of numerous new genera within the interval of the undifferentiated triangularis Zone shortly after the Frasnian–Famennian (F–F) mass extinction. Cyrtospiriferid brachiopods of the subfamilies Cyrtospiriferinae and Cyrtiopsinae are important elements of the early Famennian post-extinction survivor and recovery faunas that migrated and radiated rapidly to occupy niches vacated by extinct clades of late Frasnian brachiopods.