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.

Gymnolaemate bryozoans are common encrusters on bivalve shells from the early to middle Albian parts of the Glen Rose and Walnut formations of southcentral and northcentral Texas. Here, we report for the first time the presence of seven gymnolaemate bryozoans, all of which represent new species. They include the bioimmured ctenostome Simplicidium jontoddi n. sp., and the cheilostomes Rhammatopora glenrosa n. sp., Iyarispora ikaanakiteeh n. gen. n. sp., Iyarispora chiass n. gen. n. sp., Charixa bispinata n. sp., Charixa sexspinata n. sp., and Charixa emanuelae n. sp. The Glen Rose bryozoans slightly antedate the commencement of an explosive bryozoan radiation and the first appearance of neocheilostomes in the late Albian. Although the diversity of cheilostomes in the Glen Rose and Walnut formations is similar to that of cyclostomes, cheilostomes are more abundant and produced larger colonies. These formations therefore yield the oldest known bryozoan assemblage dominated in terms of biomass by cheilostomes. The genus concept of Charixa is discussed and amended.

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Multivariate morphometric analysis was applied for differentiation of closely related species and evaluation of intra- and interspecific variation in Manipora from the Selkirk Member, Red River Formation, in southern Manitoba. Seven morphological characters were quantified in transverse thin sections of 46 coralla and statistically tested for selecting effective characters in discriminating species. Cluster analysis was performed on a raw data matrix coordinated with 46 coralla by three selected characters. Two major clusters on the resulting dendrogram were regarded as morphospecies, following comparative examination of the coralla using serial sections. Cluster analyses were also conducted on principal component score matrices obtained from the raw data set coordinated with 46 coralla by all seven characters, and from an experimental data set including the 46 coralla plus two replicates of each and six of the characters. the results agree closely with the first cluster analysis, but discrimination of morphospecies was slightly degraded. the validity of two morphospecies recognized in the first cluster analysis was verified by discriminant analyses, descriptive statistics, and bivariate plots. the results show that tabularium area is the most meaningful character for distinguishing these morphospecies; ranges of variations of the other six characters overlap between morphospecies.

Another cluster analysis like the first was performed, but with the addition of 11 type specimens and reference coralla of Manipora species from the Upper Ordovician of southern and northern Manitoba and Texas. Based on this analysis, together with comparative examination of thin sections, the two morphospecies are identified as valid species: M. amicarum Sinclair, 1955 and M. manitoba (Sokolov, 1955). Manipora magna Flower, 1961 is considered to be a synonym of M. amicarum, while M. trapezoidalis Flower, 1961 and M. garsonensis Caramanica, 1992 are considered to be synonyms of M. manitoba, and the hypotypes of M. amicarum of Nelson (1963) are assigned to M. manitoba.

Re-evaluation of teeth referred to the Late Cretaceous shark Ptychodus polygyrus from North America are hereby determined to be synonymous with another species having similar tooth morphology, Ptychodus marginalis Agassiz. Ptychodus marginalis differs from P. polygyrus by having an elevated and rounded tooth crown with transverse ridges restricted centrally on the apex of the crown with a clearly defined marginal area. The type specimen of P. marginalis was described from Middle Cenomanian to Middle Turonian deposits in the English Chalk, and teeth possessing identical tooth morphologies are found within contemporary units in North America, whereas teeth having the typical P. polygyrus morphology are restricted to Late Santonian-Early Campanian deposits.

The middle Campanian Wolfe City Sand in northeastern Texas yields a distinctive ammonite and inoceramid fauna with Patagiosites sp., Placenticeras sp., Hoplitoplacenticeras (Hoplitoplacenticeras) minor n. sp., Baculites mclearni Landes, 1940, Trachyscaphites spiniger (Schlüter, 1872) porchi (Adkins, 1929), Inoceramus (Cordiceramus) azerbaidjanensis Aliev, 1939, and I. (Endocostea) balticus Boehm, 1907. The last-named four species allow a direct correlation with the Baculites mclearni zone of the Western Interior of the United States. The base of this zone has been dated at 79.9 ± 3.2/79.2 ± 1.6 Ma on the basis of K/Ar determinations on biotite from a bentonite. Inoceramus azerbaidjanensis is also known from the Campanian of the U.S.S.R. in Azerbaidjan (where the species was first described), western Turkemenia, Georgia, the northern Caucasus, the Crimea, and Donbass.

Cyriacotheriidae are a family of unusual small-bodied pantodonts known from the Paleocene of the Western Interior of North America. Cyriacotheriids possess a suite of dental characters similar to that of pantodonts (e.g., molar dilambdodonty, lingual molar hypoconulids), as well as several divergent features (e.g., molarized premolars, strong molar conules) that have been interpreted as “dermopteran-like.” the unusual combination of pantodont and dermopteran-like characters, combined with a limited fossil record, has made attempts at understanding the broader relationships of Cyriacotheriidae difficult. This paper reports on a new genus and two new species of cyriacotheriids from the Paleocene of Alberta, Canada, with both species significantly older than those of the only previously described cyriacotheriid, Cyriacotherium. Collectively, the dentitions of these new taxa exhibit derived characters seen in Cyriacotherium (e.g., robust molar conules, strong molar dilambdodonty) in addition to a number of plesiomorphies seen in more basal pantodonts (e.g., conspicuous molar entoconids, deep premolar ectoflexus) and, importantly, posterior premolars that are weakly molariform and non-dilambdodont. A phylogenetic analysis of the new cyriacotheriid, basal pantodonts, dermopterans, and dermopteran-like eutherians resulted in Cyriacotheriidae nesting within a monophyletic Pantodonta. the results strengthen previous hypotheses regarding the pantodont affinities of the family, and suggest that the dermopteran-like features seen in the more derived Cyriacotherium were acquired convergently. Although the discovery of new cyriacotheriids sheds light on the evolutionary history of the family, it cannot resolve the ongoing questions of pantodont origins; nonetheless, their discovery in strata of early Paleocene age indicates that significant parts of the evolutionary history of Cyriacotheriidae, and North American pantodonts more generally, have yet to be discovered.

The Oligocene strata of the Qom Formation from the Tajar-Kuh section, Central Iran, are rich in various Larger Benthic Foraminifera (LBF). Morphometric studies of the internal features of the LBF tests were carried out based on matrix-free specimens from seven samples. The LBF assemblage studied in 24 populations mainly contains representatives of two nummulitid (the reticulate Nummulites bormidiensis Tellini, 1888, only in the lower three samples, and the radiate Nummulites kecskemetii Less, 1991 in all samples) and of two lepidocyclinid lineages. Of the latter, Nephrolepidina praemarginata (R. Douvillé, 1908) occurs in all the samples, whereas Eulepidina formosoides H. Douvillé, 1925 is present in the lower six samples. In the upper sample, the slightly more advanced Eulepidina ex. interc. formosoides H. Douvillé, 1925 et dilatata (Michelotti, 1861) is recorded. Due to the very similar taxonomic composition of the Tajar-Kuh section with their coeval faunas of the Mediterranean, the age was evaluated in the frame of the Western Tethyan Oligo-Miocene shallow benthic zonation (SBZ). Although the presence of E. formosoides suggests late Rupelian (SBZ 22A Zone) age, the occurrence of Heterostegina assilinoides, N. kecskemetii, N. bormidiensis, and Planolinderina sp. preferably represents the SBZ 22B Zone of the early Chattian. Based on the obtained results, at least the lower six samples can indicate the very basal part of the Chattian. More advanced Eulepidina from the uppermost sample suggests a slightly younger but still early Chattian age.

Clusters of associated colony fragments discovered weathering out of bedding planes in the Upper Ordovician of the Cincinnati, Ohio, region provide a rare opportunity to quantify intracolony variation in ramose stenolaemate bryozoans. Sixteen colonies were reassembled as completely as possible from 198 fragments, and the following colony-level characters were measured: colony dimensions, branch link length and diameter, and branch order. Results indicate that branch link length and diameter systematically decrease as colonies grow via branch bifurcation. Branching ratio (i.e., the number of distal first-order branches divided by the number of immediately proximal second-order branches) appears to be more genetically than environmentally controlled and to be consistent among orders of stenolaemates and perhaps across the phylum. Colonies with endozones mined out by endoskeletozoans result in broken branches as opposed to pristine growing tips. This varies stratigraphically, perhaps in response to the distribution of the boring animals. The rarity of borers and the systematic proximal increase in branch diameter in these colonies suggest the zooids in the proximal portions of the colonies were alive at the time of colony death. If the time and effort can be invested in reassembling colonies, these morphometric data can then be applied to taxonomic, phylogenetic, and paleoenvironmental studies.

Plesiadapiforms represent the first radiation of Primates, appearing near the Cretaceous-Paleogene boundary. Eleven families of plesiadapiforms are recognized, including the Paromomyidae. Four species of paromomyids from the early Eocene have been reported from Europe: Arcius fuscus Russell et al., 1967, Arcius lapparenti Russell et al., 1967, and Arcius rougieri Godinot, 1984 from France and Arcius zbyszewskii Estravís, 2000 from Portugal. Other Arcius specimens from the early Eocene are known from Masia de l’Hereuet (Spain), Abbey Wood (England), and Sotteville-sur-Mer (Normandy, France). A cladistic analysis of the European paromomyids has never previously been published. A total of 53 dental characters were analyzed for the four Arcius species and the specimens from Spain, England, and Normandy. The results of a parsimony analysis using TNT agree with previous conceptions of A. zbyszewskii as the most primitive member of the genus. Consistent with existing hypotheses, Arcius rougieri is positioned as the sister taxon of A. fuscus and A. lapparenti, and the results suggest that the fossil from Normandy is A. zbyszewskii. However, the English fossil pertains to a primitive lineage, rather than grouping with A. lapparenti as had been suggested; as such it is recognized here as a distinct species (Arcius hookeri new species). The Spanish fossils cluster together with the French species but do not show the previously proposed special relationship with A. lapparenti and are sufficiently distinct to be placed in a new species (Arcius ilerdensis). Arcius is recovered as monophyletic, which is consistent with a single migration event from North America to Europe around the earliest Eocene through the Greenland land bridge.

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Universal elemental homology (UEH) underpins recent understanding of peristomial and ambulacral elemental homology of pentaradiate echinoderms by providing a uniform set of terminology to construct phylogenetic characters. Variation in the expression of these elements provides evidence for phylogenetic relationships. Two nonhomologous sets of plates border the peristome and are associated with two nonhomologous sets of floor plates forming the ambulacral food groove. Some edrioasteroid-grade and eocrinoid-grade echinoderms have ambulacral systems formed from oral frame plates and adradial floor plates, whereas most blastozoans and crinoids bear oral plates and abradial floor plates. These plates are expressed in a variety of ways among echinoderms, but nearly all can be reconciled with the underlying model. Arguments against UEH are methodologically flawed and confuse many terms and interpretations.

Hollinacean and kirkbyacean ostracodes are rare to abundant components of the ostracode faunas in the Pennsylvanian marine units of the Appalachian Basin. The diversity of these two groups appears lower in the Appalachian Basin than as reported from the Eastern Interior Basin. Thirty-six taxa, nine hollinelliid and 27 kirkbyiid, are identified. Three new species, Amphissites (Amphikegelites) sohni, Kegelites cooperi, and Kirkbya causa, are proposed.

Kirkbyaceans from the Morrowan–Atokan portion of the section compare favorably with those described from the Eastern Interior Basin. The Shleesha rothi Zone of the Eastern Interior Basin can be recognized in the Appalachian Basin, comprising Morrowan and Atokan units. Desmoinesian units in the Appalachian Basin contain many taxa extending up from the Atokan, but several new forms appear. Of the latter, Kegelites cooperi is the most diagnostic species and is the name bearer for the Kegelites cooperi Zone. Missourian–Virgilian faunas are significantly different from those in the Desmoinesian, but are not separable from each other. These units are grouped together into the Kegelites dattonensis Zone.

New specimens representing species of Cyrtiopsis Grabau, 1923, described by Grabau (1931a) were recovered in samples from the Late Devonian deposits of the Changlongjie Member of the Xikuangshan Formation in central Hunan Province of South China. Associated Famennian age conodonts and morphotypes of the rhynchonellid brachiopod Yunnanellina lineage fix the ranges of species of Cyrtiopsis and related taxa in the Xikuangshan Formation within the interval of the Middle triangularis Zone through the Lower crepida Zone (early Famennian) in central Hunan Province.

Detailed study and comparison of external and internal shell structures of the type species of Cyrtiopsis Grabau, 1923, and related species described in Grabau (1931a) shows that Cyrtiopsis from South China includes the type species, C. davidsoni (embodied by the holotype), and C graciosa. Both of these species are shown to lack a delthyrial plate. Grabau's paratypes of C. davidsoni are considered to belong in Cyrtiopsis intermedia Grabau, 1931. The species C. kayseri Grabau, 1931, and C. shensiensis Grabau, 1931, are also deemed synonyms of C. davidsoni Grabau, 1923 (as restricted above). “Cyrtiopsis” intermedia differs from other species of Cyrtiopsis by development of a short delthyrial plate and its systematic position remains uncertain.

The genus Pseudocyrtiopsis is proposed with Cyrtiopsis spiriferoides Grabau, 1931, as the type. Pseudocyrtiopsis new genus is distinguished from Cyrtiopsis Grabau, 1923, by its alate hinge and development of a delthyrial plate. Comparisons of species of Cyrtiopsis from South China with cyrtospiriferid brachiopods identified as Cyrtiopsis by Crickmay (1952) demonstrate that none of the early Famennian species from western Canada can be assigned to the genus as revised here, although C. mimetes Crickmay, 1952, is closely related to “C.” intermedia Grabau, 1931.

A correct interpretation of ligament ontogeny and structure is essential for establishing phylogenetic relationships among higher taxa in the bivalve superorder Pteriomorphia. Recent research on pteriomorphian ligaments has focused on understanding ligament morphospace (Thomas et al., 2000; Ubukata, 2003) and evolutionary pathways. In this regard, studies of the transition from larval to post-larval and adult ligaments (Malchus, 2004) have been especially fruitful.

An ostracode fauna is described from lacustrine sediments of the Hettangian, Lower Jurassic, Whitmore Point Member of the Moenave Formation. The Moenave is well known for its rich, Late Triassic?–Early Jurassic fossil record, which includes fossil fishes, stromatolites, ostracodes, spinicaudatans, and a diverse ichnofauna of invertebrates and vertebrates. Four ostracode species, all belonging to the suborder Darwinulocopina, were recovered from these sediments: Suchonellina globosa, S. stricta, Whipplella? sp. 1, and W.? sp. 2. The diversity and composition of the Whitmore Point Member ostracode fauna agree with previous interpretations about Lake Dixie and nearby paleoenvironments as shallow lakes inhabited by darwinulocopine species that survived the effects of the Central Atlantic Magmatic Province and the subsequent end-Triassic extinction and quickly recolonized these areas, thanks to asexual reproduction by parthenogenesis. The Lake Dixie region, in its geographical isolation, could represent the last episode of darwinulocopine dominance in nonmarine environments before the Late Jurassic diversification of the cypridocopine/cytherocopine modern ostracodes.

The echinoids Salenia cascadensis n. sp., Stomechinus? dissimilaris n. sp., Glyptocidaris sp., Arbacia abiquaensis n. sp., Lytechinus baldwini n. sp., Gagaria crenularis n. sp., and Kewia marquamensis n. sp. occur in the Late Oligocene (Chattian) Scotts Mills Formation near Silverton, Oregon, just north of 45°N latitude. The echinoids occur in shallow-water sediments deposited among basaltic sea stacks along a rockbound, storm-dominated marginal marine environment. Except for Kewia, these occurrences mark a more northerly limit for these genera in the northeastern Pacific and add to their stratigraphic range.

A new fossil ant genus, Bilobomyrma new genus, and two new species are described based on males from the late Eocene Rovno (B. ukrainica n. sp.) and Baltic (B. baltica n. sp.) ambers. We tentatively place this genus in the myrmicine tribe Formicoxenini. Bilobomyrma is characterized by its 13-segmented antennae without an apical club; by the short scape, which is subequal to the length of the first and second funicular segments together; by the shape of the second funicular segment, which is distinctly longer than the any other funicular segment except for the apical one; by the presence of notauli on the scutum; by the absence of spurs on the middle and hind tibiae. At the same time, Bilobomyrma differs from other myrmicine genera by the peculiar shape of its clypeus, having a strongly incised medially, bilobed anterior margin, and its forewing venation: the wings have three closed cells—mcu, 1+2r and 3r; the cell 3r is very short, only twice as long as its width; the distal section of veins RS and M diverge from the cell 1+2r separately.

A new medusoid hydrozoan, Plectodiscus malayites n. sp., belonging to the Family Velellidae is described from Carboniferous rocks of the Malay Peninsula. They are preserved as flattened internal float structures or pneumatophores and are the first examples from this part of the world. In contrast to other occurrences, the great abundance of these sailed organisms suggests that, like extant species of Velella, these organisms were an important component of the pelagic fauna and were at least locally abundant in open seas of the late Paleozoic.

A new terebratellid brachiopod species, Modestella jeletzkyi n. sp., is described from the Early Cretaceous of Prince Patrick Island, Northwest Territories, Canada. The occurrence extends the paleobiogeographic range of Modestella from northwest Europe into the northern high-latitudes of the North American continent. This new record of Modestella suggests brachiopod dispersal between northwest Europe and North America via the East Greenland Seaway, probably during the Albian. The occurrences of two other Cretaceous terebratellid genera, Advenina and Psilothyris, are updated. They are both homeomorphic with Modestella. Advenina, from the Tethyan and Jura regions of Europe, is now recorded from the Early Cretaceous of Sardinia. The occurrence of Psilothyris in North America and Europe is best explained by dispersal through the opening central Atlantic Ocean, indicating the continuation of Hispanic Corridor-type faunal links established during the Jurassic.

Iheringinucula, a new Tertiary genus of the family Nuculidae, is proposed. This taxon is known only from the Patagonian region (Argentina), and its range is from the late Eocene to the early Miocene. Two species are known: Iheringinucula tricesima (Ihering) from the Monte León Formation (upper Oligocene-lower Miocene) and Iheringinucula crassirugata new species from the San Julián Formation (upper Eocene-lower Oligocene?) and the Monte León Formation.

An amphibian trackway collected in minespoil from the Cross Mountain Formation in the Cumberland Mountains of East Tennessee represents the first known Middle Pennsylvanian (Westphalian) amphibian trackway from the southeastern United States. The tracks are impressed onto the upper surface of a bed of fine-grained, cross-laminated sandstone and siltstone, deposited in an upper delta plain environment.

The trackway was made by an amphibian with a long glenoacetabular distance and low pace-angulation. The imprints show five digits on the pes and four on the manus. Average measurements for the trackway are: stride, 8.4 cm; pace angulation, 76.1° (manus), 63.1° (pes); track width, 5.5 cm (manus), 6.7 cm (pes); glenoacetabular distance, 16.7 cm. The manus impression averages 2.8 cm long by 3.1 cm wide, and the pes averages 3.8 cm long by 3.1 cm wide. A tail drag is conspicuous along the entire length of the trackway and has a minimum radius of curvature of 9 mm.

The trackway is assigned to Matthewichnus caudifer n. ichnosp. on the basis of similarities to published material. The trackmaker was probably a temnospondyl labyrinthodont, considering the size of the animal (thus excluding lepospondyls) and the fact that it had a four-digit manus (thus excluding reptiles and anthracosaurian labyrinthodonts).