Galecyon is one of the first appearing hyaenodontid creodonts, as well as one of the most poorly known. New specimens greatly improve our understanding of the morphology of this early Eocene genus, thereby enhance knowledge of the earliest radiation of Hyaenodontidae, and include the first associated upper dental remains, as well as fragmentary cranial remains. The new records substantially expand the stratigraphic range of the genus and allow recognition of two new species. The first, Galecyon peregrinus n. sp., is a small, early species that includes the first records of Galecyon from the earliest Eocene Wa-0 interval. The second, Galecyon chronius n. sp., is a large, terminal species, represented by numerous specimens that extend the range of the genus into the late Wasatchian. The type species, G. mordax, is restricted to specimens that are intermediate in size and stratigraphic position. Phylogenetic analysis of early hyaenodontids confirms the monophyly of Galecyon and places it basal to Prolimnocyon, Prototomus, and Pyrocyon. Arfia is identified as the earliest diverging hyaenodontid sampled, contrasting with prior support for a more crownward position. Prototomus martis is more closely allied to Pyrocyon than to other species of Prototomus. The three North American species of Galecyon form a probable anagenetic lineage.

The discovery of platy limestone deposits in northeastern Mexico has led to the collection of well-preserved stramentids of early Turonian age from Vallecillo, state of Nuevo León, and of early Coniacian age from El Carranza, state of Coahuila. Stramentum (Stramentum) pulchellum (Sowerby, 1843) colonized the ammonite shells during the lifetime of the animals, occasionally in two subsequent generations. Colonization of the ammonite shell by Stramentum (S.) pulchellum was hindered by strong ornamentation only. The ammonites did not interfere with their epizoans. Colonization during lifetime shows that these ammonites dwelled in well-oxygenated water levels near the surface, and most stramentids were embedded alive. The known paleobiogeographic occurrence of Stramentum (S.) pulchellum and its long stratigraphic occurrence are considerably enlarged by our findings. The pseudoplanktonic mode of life of Stramentum, and attachment to ammonite shells, may have been a response of a once benthic organism to repeated oxygen-deficient conditions on the seafloor of mid-Cretaceous oceans, i.e., to oceanic anoxic events (OAEs).

A tuffaceous claystone sample collected from a seamount flank of the Mariana Trench's ocean-ward slope by the Japanese submersible “Shinkai 6500” yielded very well-preserved earliest Cretaceous radiolarians. Initial spicule-bearing spherical radiolarians assignable to the families Centrocubidae and probably Entactiniidae have been identified in this radiolarian fauna. Based on the initial spicule and the connecting arches, we describe one new genus, Marianasphaera, belonging to the family Centrocubidae and another new genus called Shinkaiera, which is questionably assigned to the family Entactiniidae. Three new species, Marianasphaera ogawai, M. multispinosa, and Shinkaiera fragilis, are also described. These radiolarians provide important data, filling the gap between Triassic and Cenozoic initial spicule-bearing spherical radiolarians.

The trinucleid trilobite Bancroftolithus Baldis and Pöthe, 1995 includes a group of species from Sandbian strata of the Argentine Precordillera. The monotypic Hunickenolithus Baldis and Pöthe, 1995 from the Las Aguaditas Formation at its type locality in San Juan Province is placed in the synonymy of Bancroftolithus. Of four nominal taxa from the Las Aguaditas Formation, B. pozensis Baldis and Pöthe, 1995, and B. hughesi Baldis and Pöthe, 1995 are retained, and both are revised based on new collections from the type locality that include ontogenetic series from the protaspid period. Two protaspid stages are recognized in both species. Three additional species (Bancroftolithus alki n. sp., B. cf. B. pozoensis, Bancroftolithus sp.) from broadly coeval strata in the Las Plantas Member of the Las Vacas Formation in La Rioja Province are identified as the closest relatives of the Las Aguaditas species. Bancroftolithus alki also occurs in the Los Azules Formation in San Juan Province. The five species included in this regional clade exhibit significant morphological differences in the lower lamellae, an unusual feature among the Trinucleidae. Bancroftolithus is evidently most closely related to the Australian Katian genus Parkesolithus. The two are not convincingly assigned to any of the existing trinucleid subfamilies.

An Erpetopus trackway recorded in the Lower Permian Collio Formation (Orobic Alps, northern Italy) is investigated as a source of data to reconstruct ancestral patterns of locomotion in eureptiles. The inferred small-sized captorhinid-“protorothyridid” producer cut an inclined muddy surface dragging its front limb digits, tail, and belly on the ground. Integrating ichnological and anatomical data we suggest that small captorhinids (“protorothyridids”) locomotion was performed with an obligatory, rigid sprawling posture with the trunk only slightly lifted from the substrate in a low, sprawled ‘belly walk’.

It was shown recently that Tetradium Dana, 1846 (type species: Tetradium fibratum Safford, 1856), a common Middle and Upper Ordovician fossil, is a calcareous filamentous florideophyte alga (Phylum Rhodophyta) (Steele-Petrovich, 2009a, 2009b), and not a tabulate coral or a chaetetid sponge, as traditionally classified. Reassigning Tetradium Dana from an animal to an alga subjects it to the International Code of Botanical Nomenclature (ICBN) (McNeill et al., 2006), which makes it a later homonym of Tetradium Loureiro, 1790 (see Farr et al., 1979), a Recent tree of the citrus family (Rutaceae). According to the ICBN (Articles 14, 53.1, 54.1), the name Tetradium Dana cannot be conserved and must be replaced, since Tetradium Loureiro is currently in use.

A new species of chiton is described from early Miocene deposits of the Monte León Formation, in Santa Cruz Province, Argentina. Callochiton monteleonensis n. sp. clearly differs from known fossil and Recent species of the southwestern Atlantic because the central area of its intermediate valves has a stepped appearance, in which each step is marked by a longitudinal rib. It is similar to Callochiton kapitiensis Mestayer, 1926, a Recent species from New Zealand. Biogeographic implications are discussed. This is the first record of a polyplacophoran from Neogene deposits of Argentina.

Castor, the extant beaver, is an important member of North American and Eurasian communities, altering ecosystems and landscapes wherever it occurs. Castor has a fossil record extending back to the late Miocene in Europe, Asia, and North America. The origin and early evolution of this genus is unclear but it likely originated in Eurasia and subsequently dispersed to North America from Asia in the late Miocene. A new record of Castor from the Rattlesnake Formation of Oregon represents the earliest occurrence of the genus in North America. The age of this new find is inferred through radiometric and magnetostratigraphic dating to be between 7.05 and 7.3 Ma. This age is supported by the co-occurrence of another beaver, Dipoides stirtoni, which is characteristic of early Hemphillian deposits. This find indicates that Castor had dispersed to North America by the early Hemphillian, and helps resolve the timing of divergence between North American and Eurasian beavers. The Rattlesnake Formation specimens are not differentiable from other North American specimens of C. californicus in morphology or size. This suggests Castor changed little after dispersing to North America, whereas the endemic castoroidine beavers changed dramatically after its arrival.

In contrast to the immense effort that has been put into the geological survey and stratigraphic study of the Neogene of Bocas del Toro region (Panama), little research has been done on the systematics of this region's rich gastropod assemblages. This is the first paper dealing primarily with the Bocas Neogene gastropod assemblages (Strombidae) since the pioneer work of Olsson (1922). Neogene strombid assemblages of the Dominican Republic have recently been reviewed and updated, and, therefore, the Strombidae are a suitable starting point for the revision of the gastropod assemblages from the Neogene of Bocas del Toro. Six species of Strombus are described, three of them new: S. acanthospira n. sp., S. pugiloides, S. gatunensis, S. elegantissimus n. sp., S. vermeiji n. sp. and S. cf. floridanus.

Šnadjr (1980, p. 76) erected the proetid trilobite subgenus Coniproteus (Ryckholtia), with the type species Proetus ryckholti Barrande, 1846, from the Silurian (Ludlow, Kopanina Formation) of the Prague Basin, Czech Republic, perhaps better known to geologists as the Barrandian type area in Bohemia. Although originally designated as a subgenus (e.g., Chlupáč et al., 1980, p. 175; Chlupáč and Kukal, 1988, p. 114; Kříž et al., 1993, p. 819), Ryckholtia Šnadjr was subsequently elevated to generic rank (e.g., Sepkoski, 2002, p. 189, 519; Jell and Adrain, 2003, p. 441, 477; Edgecombe and Wright, 2004, p. 183).

A new species of Orthoptera, Parapleurites morrisonensis, is described from the upper Jurassic Morrison Formation of Colorado, USA. This is the first insect described from the Morrison Formation and the first orthopteran described from the Jurassic of North America. No other members of the family Locustopsidae have been described in North America previously, and the other species of Parapleurites are only known from Siberia. The lack of Jurassic Orthoptera in North America is likely due to a combination of taphonomic variables and collector bias. The discovery of Parapleurites morrisonensis and the potential for finding other Jurassic Orthoptera are important to understanding the evolution of this diverse and widely distributed group.

The early Paleocene Purgatorius Van Valen and Sloan is the most primitive plesiadapiform primate yet discovered, mostly known from middle to late Puercan strata in Montana, deposited during the interval C29N of the geomagnetic polarity time scale. Here we describe Purgatorius coracis n. sp. from the Ravenscrag Formation, at the Rav W-1 horizon, Medicine Hat Brick and Tile Quarry, southwestern Saskatchewan. This horizon occurs within C29R, making P. coracis the earliest known primate, while strengthening the evidence that plesiadapiforms, and hence primates, originated and underwent their initial evolutionary diversification in North America. Most North American mammalian local faunas correlating with C29R have been assigned to the Pul (earliest Puercan) interval zone, but the taxonomic composition of the mammals accompanying P. coracis at Rav W-1 more resembles local faunas of Pu2 age. The occurrence at Rav W-1 of Pu2 aspect mammals within C29R agrees with similar occurrences at the Hiatt and PITA Flats localities in Montana and North Dakota, also possibly correlated with C29R. The evidence from these three sites, all in the Williston Basin, suggests that in some areas of the Western Interior Pu2 aspect local faunas were coeval with those of latest Pu1 age, having evolved earlier than has commonly been assumed.

Jurassic–Cretaceous ammonites are particularly robust fossil tools in global stratigraphy and correlation. The successive evolution and extinction of these cephalopod mollusks was so rapid that many ammonite zones are no more than one million years in duration. A well-preserved ammonite specimen from the Fortissimo-1 core, Browse Basin, NW Australia is assignable to the widespread latest Jurassic dimorphic berriaselline genus, Blanfordiceras Cossmann, recorded previously from the Spiti area, Nepal, Tibet, Madagascar, Papua-New Guinea, Antarctica, and southern South America. This is the first report of ammonites of this age in the Australian region. The evolute shell of an estimated 90-100 mm diameter (when extrapolated) and pronounced ornamentation of variably bifurcating, curvilinear and flexuous ribs, intercalated with simple, non-bifurcating ribs, is consistent with Blanfordiceras wallichi (Gray, 1832), which has traditionally been restricted to the uppermost Tithonian Stage, ca. 146.5-145.5 Ma, but may well have survived into the earliest part of the Berriasian. The first recorded occurrence of this ammonite in Australia fills an anomalous absence in the paleobiogeographic distribution of Jurassic–Cretaceous boundary ammonites in the Indo-SW Pacific Subrealm with important implications for the calibration of offshore rocks and wells in Australia.

A complete molted exoskeleton of the asteropygine phacopid trilobite Greenops widderensis Lieberman and Kloc, 1997 from the Middle Devonian (Givetian) Widder Formation in southwestern Ontario, Canada that has suffered predatory trauma provides insights into the sequence of regeneration of segments. The molt configuration is such that it is possible to interpret the molting technique used by the trilobite. Predatory trauma affected four areas of the exoskeleton. The pygidium shows loss of the spinose margin on one side and damage to a single spine on the other; one genal spine has been broken and partially regrown; and the posterior of the glabella has been removed. It is thought that the first three traumas occurred during life, as these areas affected show signs of exoskeletal regeneration. The fourth trauma probably occurred to the exuvium. Analysis of the degree of regeneration of the pygidial pleurae indicates that there was an anteroposterior polarity to the regeneration. Other examples in the literature suggest that this regeneration polarity pattern may have been widespread in trilobites. It is suggested that, as in modern arthropods and annelids, this sequential regeneration was under the control of segmentation polarity genes.

Recent collecting provided fossil chitons (Mollusca, Polyplacophora) from upper Eocene to lower Oligocene deposits of Washington State, U.S.A. The study material consists of 140 valves from six localities in the Quimper, Makah, Lincoln Creek, Crescent and Gries Ranch formations. The material is mostly incomplete or very fragmented and/or worn so that a precise appreciation of diagnostic features has been in many cases difficult if not impossible. Fourteen species were identified, seven are described as new: Lepidopleurus propecajetanus n. sp., Leptochiton sp., Ischnochiton goederti n. sp., Ischnochiton? sp. A, Ischnochiton? sp. B, Stenoplax quimperensis n. sp., Stenoplax sp. A, Stenoplax sp. B, Lepidozona cowlitzensis n. sp., Lepidochitona lioplax (Berry, 1922), Lepidochitona washingtonensis n. sp., Lepidochitona squiresi n. sp., Lepidochitona sp. and Craspedochiton eernissei n. sp. The only species previously described from the study area is Lepidochitona lioplax and it is also the most common chiton in the study material (67% of the total). No species other than L. lioplax has been found in more than one locality. In four of these localities only a single species has been collected. The basal Lincoln Creek Formation at the Porter Creek site supplied the richest and most diverse chiton assemblage with seven species and 86% of the valves. The discovery and formal identification of such a diverse Paleogene fauna from the northeastern Pacific provides a comparative base for a better appreciation of Polyplacophora biogeography and evolution.

This contribution presents the first description of crinoids from western margin of Parnaíba Basin. It also presents their first description in the Pimenteira Formation (Devonian of the Parnaíba Basin, state of Tocantins, Brazil). The material is represented by hundreds of columnals, pluricolumnals, as well as isolated calyx plates. Columnal and pluricolumnal morphology allowed the identification of Laudonomphalus aff. L. tuberosus, and Exaesiodiscus dimerocrinosus n. sp. Based upon calyx plate morphology a new Rhodocrinitidae species was erected, Monstrocrinus incognitus n. sp. The genera Exaesiodiscus, Laudonomphalus, and Monstrocrinus were previously described from the Devonian of Amazonas Basin. Exaesiodiscus dimerocrinosus is also identified from the northwest margin of Paraná Basin. The Monstrocrinus occurrence is rare in the Middle Devonian, until now known in Germany, Spain, and Algeria Lower Devonian (upper Emsian) and only in northern Brazil in the Middle Devonian (Eifelian.) These facts provide valuable arguments for paleogeographic interpretations regarding the pattern of distribution of invertebrates in this region of Gondwana and suggest potential migration routes in northern Gondwana during the Devonian.

Savage (1995, p. 550, figure 8.8, 8.9) named a conodont Polygnathus praetrigonicus from the Middle Devonian Wadleigh Limestone, southeastern Alaska. This name is now known to be a junior homonym of Polygnathus praetrigonicus Bardashev (1992, p. 56, 57, pl. 2, figs. 32–34), a taxon from the Middle Devonian of the Zeravshan Range, southern Tien-Shan. The southeastern Alaskan fossil is clearly a different species and I here rename it as Polygnathus bagialensis after Port Bagial, near Alberto Island from where the holotype of the species was collected.

Tubular fossils, up to 2 mm in diameter and 60 mm in length, occur rarely in the upper Martinsburg Formation (Upper Ordovician), northeastern Tennessee Appalachians, U.S.A. The fossils are unbranched, straight or slightly bent, occasionally twisted and wrinkled, and not significantly tapered. Orientation of the fossils within shallow-marine tempestites suggests that they represent remains of organisms that were broken, transported, and deposited by storm waves and currents. The fossils are morphologically similar to many of the previously identified species belonging to the genus Sphenothallus, a relatively rare tube-dwelling Paleozoic marine invertebrate. Owing to the limited evidence for distal widening of the tubes, lack of holdfasts, and carbonaceous rather than phosphatic composition, the affinity of these fossils remains uncertain, and we refer to them as Sphenothallus-like.

Three new specimens of middle Eocene cetaceans are reported from the Pisco Basin of southern Peru. All three specimens originate from the Paracas Formation and their minimum age is constrained to about 37 Ma using 40Ar/39Ar dating of ash collected ~100 m up section from the source localities. Two new genera of archaeocete cetaceans are described along with additional material of another distinctive protocetid, which is not named pending the discovery of more complete material. Phylogenetic analysis resolves the two new genera within Basilosauridae, while the unnamed protocetid is closely related to Eocetus. The discovery of crownward protocetids in South America demonstrates that early cetaceans may have dispersed into both hemispheres prior to evolving a fully aquatic lifestyle. Geochronologic constraints on the age of new Peruvian archaeocetes establish them as the oldest whales from South America and among the oldest known from the Southern Hemisphere, which highlights the need for better sampling of marginal marine rocks from this part of the world.

Twelve brachiopod species are described from the Cisuralian (Early Permian) Kungurian horizon of a large limestone block in the Middle Jurassic accretionary complex at Hatahoko in the Mino Belt, central Japan. Most species of the Hatahoko fauna are known from the Kungurian to lowest Guadalupian (Middle Permian) of West Texas, U.S.A. The Kungurian age is also indicated by the associated conodonts in the same limestone block. The Hatahoko brachiopod fauna, as well as some other previously-reported Guadalupian brachiopod faunas, exhibits a very strong paleobiogeographical affinity with the faunas in West Texas, U.S.A. Therefore it can be interpreted as a fauna which inhabited reef-seamount complexes close to North America in the mid-equatorial region of the Panthalassa in the late Early Permian, rifted westwards thousands of kilometers, and finally accreted onto the Japanese Island when the Western Pacific Plate subducted beneath the Eurasian Plate during the Jurassic.