In 2006, we (Grande & Hilton, 2006) described a well-preserved fossil sturgeon (Acipenseridae) from the Late Cretaceous of Montana and proposed the name †Psammorhynchus longipinnis Grande & Hilton for the new species. Through accidental discovery of an on-line taxonomic database of flatworms (Tyler et al., 2006) and subsequent investigation, we recently discovered that the genus-group name is preoccupied by Psammorhynchus Meixner, 1938 in Platyhelminthes (“Turbellaria”). Therefore, under Article 60 of the International Code of Zoological Nomenclature (ICZN, 1999), a replacement name is required for the junior homonym †Psammorhynchus Grande and Hilton.

A study of Upper Triassic (Norian) thalamid sponges (“sphinctozoans”) from the Pilot Mountains, Garfield Hills, and East Range, Nevada, reveals an abundance of calcified sponges of the suborder Porata Seilacher. Two new species, Polycystocoelia silberlingi n. sp. and Neoguadalupia? norica n. sp., are added to our knowledge of five thalamid sponge taxa previously known from Nevada. All specimens have been neomorphically altered to calcite in a manner implying an original aragonite mineralogy.

At the species level, the sponges show a restricted distribution. Nevadathalamia cylindrica (Seilacher) is a species also occurring in Sonora, Mexico, and previously known from the Yukon of Canada, but all other species are endemic to west-central and northwestern Nevada. At the generic level, similarities exist with species known from the Tethyan Realm, the Yukon, and south China. The genus Polycystocoelia has been known previously only from Hubei, China, and from the Yukon Territory, Canada. Neoguadalupia was previously known only from the Lower and Upper Permian of China. The occurrence of this genus in Nevada constitutes the first record of the genus outside of the Permian System of China.

The Mount Laurel Sand at Biggs Farm, Delaware, yielded a diverse ammonite fauna comprising Pachydiscus (Pachydiscus) sp., Placenticeras cf. P. placenta (DeKay, 1828), Placenticeras n. sp., Eulophoceras sp., Nostoceras (Nostoceras) draconis Stephenson, 1941, Didymoceras cheyennense (Meek and Hayden, 1856a), Anaklinoceras reflexum Stephenson, 1941, Anaklinoceras tenuicostatum n. sp., Oxybeloceras meekanum (Whitfield, 1877), Solenoceras annulifer Morton, 1841, Baculites ovatus Say, 1820, B. undatus Stephenson, 1941, Hoploscaphites vistulensis Błaszkiewicz, 1980, and Jeletzkytes compressus (Roemer, 1841). The last named two species occur in Europe and indicate an upper but not uppermost upper Campanian horizon. Several species also occur in the Western Interior and suggest correlation with the Didymoceras cheyennense zone and part of the Baculites compressus zone of the upper Campanian in that region.

The microstructure of the non-window portions of the shell of Corculum cardissa resembles other Fraginae, with predominantly fibrous prismatic outer, branching crossed lamellar middle, and complex crossed lamellar inner layers. Both the anterior and posterior windows in its shell reflect reduced pigmentation and incursion of the outer shell layer, but the posterior windows involve deeper incursion plus reduction of the outer and middle sublayers of the outer shell layer and microstructural modification of the middle shell layer to enhance light transmission. The planoconvex shape of the posterior windows has more likely evolved to direct and focus light toward the deeper, zooxanthellae-rich gills and anterior mantle, than to merely disperse light.

Eocene ostracodes are described from the Japanese Islands for the first time. These ostracodes, from the Iojima Group in southwestern Japan, are represented by cosmopolitan and low- to midlatitudinal paleobiogeographic groups as well as an endemic group. Based on the distributions of selected genera, the ostracode fauna of the Iojima Group has tropical to subtropical affinities, affirming links with the Tethys Sea. Six species are described as new: Cytheropteron liue, Eopaijenborchella kamiyai, Eopaijenborchella okinoshimaensis, Ambtonia? matsubarai, Paracypris? kuritai, and Trachyleberis? funatsuensis.

The Middle and early Late Triassic of southern China is well known for a remarkable diversity of marine vertebrates, particularly reptiles, including an abundance of intriguing new forms (e.g., Jiang et al., 2005; Hu et al., 2011; Li et al., 2016). Here we describe a new diapsid from Yunnan Province. It possesses an elongate neck that exhibits a remarkable similarity to that of many Protorosauria, yet in other respects the skull and postcranium are much less derived.

The new taxon is part of the so-called Panxian-Luoping Fauna and the deposits correspond to the Upper Member of the Guanling Formation, comprising thin to medium bedded, gray to dark-gray laminated marly limestone and limestone, with several layers of bentonite intercalated in the fossil level at Panxian (Wan, 2002; Motani et al., 2008; Jiang et al., 2009). Their age is Pelsonian (middle Anisian, Middle Triassic) as is indicated by the conodont Nicoraella kockeli Zone (Sun et al., 2006; Zhang et al., 2009). A recent U-Pb study indicates the absolute age of these middle Anisian beds to be close to 244 Ma (Wang et al., 2014).

The richly fossiliferous Ekspedition Bræ Formation of North Greenland yields a typical oligospecific fossil assemblage with well-preserved trilobites, helcionelloids, and lingulate brachiopods. The trilobites include Itagnostus subhastatus new species, Itagnostus sp. cf. I. gaspensis (Rasetti, 1948), Elrathina aphrodite new species, Elrathina athena new species, Elrathina hera new species, and Elrathia groenlandica new species—a fossil assemblage typical of the Bathyuriscus-Elrathina Zone as known from the Cordilleran regions of Laurentia. Excellent preservation allows a detailed assessment of the prosopon and elucidates aspects of the ontogenetic development of Elrathina and Elrathia. An evaluation of Elrathina includes a redescription of its type species, E. cordillerae (Rominger, 1887), based on the type material, and indicates that most specimens collected from the Burgess Shale and previously dealt with as E. cordillerae represent a new species.

Gastropods are described for the first time from the Kersadiou Formation (middle Givetian) in the vicinity of Brest, Brittany, northwestern France. Twenty-three species of gastropods are recognized. New taxa include the new genera, Calvibembexia, Kersadiella, Breizospira, Finisterella, Parahormotomina, and Nodoloxonema, represented by the new species Calvibembexia lethiersi, Kersadiella babini, Breizospira crozonensis, Finisterella tibidiensis, Parahormotomina sibertae, and Nodoloxonema plusquelleci. Further new species include: Sinuitina (Sinuitina) morzadeci, Crenistriella armoricana, Patellilabia (Phragmosphaera) ponceti, Angyomphalus (Eoangyomphalus) weyanti, Eoplatyzona ongaroae, Murchisonia oehlerti, and Hormotomina fiacrensis. The biogeographic affinities of the fauna show a strikingly unusual admixture of Eastern Americas Realm taxa such as Hormotomina and Crenistriella. This suggests that during the middle Givetian, the Massif Armoricain (northwestern France) represented an area of Realm-boundary mixing between the Old World and Eastern Americas Realms, while older Devonian gastropod faunas of the Massif Armoricain are wholly of Old World Realm type.

Organic-walled fossils, such as graptolites and Chitinozoa, show a high degree of transparency to near infrared radiation relative to visible light. Infrared video microscopy (IVM) provides real-time images of the three-dimensional form and internal structure of many specimens that are opaque to visible light. An infrared video camera can be mounted on a biological or petrographic, transmitted-light microscope, and with the addition of a monitor and video printer, images can be viewed and directly printed. With the use of a digital frame-capture system, the IVM images can be digitally stored for analysis, enhancement and printing. As compared with scanning electron microscopy, which only reveals the external form, IVM shows such features as fusellar growth bands and internal septa of graptolites and the prosome structure of Chitinozoa. This method eliminates the need for chemical clearing of specimens for study in visible light, which damages the surface texture and commonly renders specimens too brittle for further manipulation. Infrared video microscopy is potentially applicable to the study of any organic-walled fossils and to the petrographic study of sedimentary organic matter.

The ediacaran Doushantuo Formation in the Yangtze Gorges area (Fig. 1.2) contains abundant silicified cyanobacterial coccoids and filaments (Y. Zhang et al., 1998), acanthomorphic acritarchs (Zhou et al., 2007), multicellular algae (Xiao, 2004), and possible animal embryos (L. Yin et al., 2007). These silicified fossils are taxonomically similar to the phosphatized fossils in the Doushantuo Formation of the Weng'an area, South China (Y. Zhang et al., 1998). However, the Weng'an assemblage contains tubular microfossils that have not been previously documented in the Yangtze Gorges area. Here we report the occurrence of secondarily silicified tubular microfossils—Sinocyclocyclicus guizhouensis (Xue et al., 1992) and Yangtzitubus semiteres new genus and species—from lenticular cherts in the upper Doushantuo Formation in the Yangtze Gorges area. Of the two named taxa, Sinocyclocyclicus guizhouensis was previously known from the Weng'an area (Liu et al., 2008). The new data extend the geographic, taphonomic, and environmental distribution of Doushantuo tubular microfossils. A fuller documentation of the Doushantuo biodiversity is also important to the evaluation of possible taphonomic or environmental biases among the three exceptional taphonomic windows—carbonaceous compression (Xiao et al., 2002), phosphatization (Xiao and Knoll, 1999), and silicification (Y. Zhang et al., 1998)—in Doushantuo black shales, phosphorites, and cherts, respectively.

The morphologic variation in Yabeina columbiana (Dawson) was carefully studied using probable topotype specimens from the Marble Canyon-Hat Creek area, southern British Columbia, and the material was compared with related species of neoschwagerinids from various parts of the circum-Pacific region. in the five Marble Canyon-Hat Creek samples examined, we found considerable individual variation in important characters, such as the size of the proloculi, and shape and development of primary and secondary transverse septula in relation to the growth stage of the test. These differences gradually changing from specimen to specimen within and among samples are thought to represent intraspecific variation within this species. Wide individual variations are also found in three different species of Yabeina from Japan, Yabeina sp., Y. kaizensis (Huzimoto), and Y. globosa (Yabe).

Most North American species of Yabeina, such as Yabeina columbiana, have morphological features such as the occurrence of primary and secondary transverse and axial septula in later whorls and the average size of proloculi that reasonably place them as early species in the genus Yabeina. Yabeina columbiana is neither a Lepidolina nor a Colania as some authors had previously thought. Evolved forms of Neoschwagerinidae in the western Cordillera of North America consist of Yabeina cordillerensis Ross, Y. cascadensis (Anderson), Y. columbiana (Dawson), Y. packardi Thompson and Wheeler, and Lepidolina dunbari (Skinner and Wilde).

The earliest North American Yabeina is thought to be Y. cordillerensis from northwestern British Columbia where it is associated with Afghanella sp., Pseudodoliolina sp., and the Wordian ammonoid Waagenoceras. This assemblage is closely comparable to that in the lowest zone of the Midian Stage in the Tethyan realm, the Afghanella robbinsae and Yabeina archaica Zone. the remainder of the known North American Cordilleran species of Yabeina are assignable to the second zone of the Midian Stage, the Yabeina globosa and Lepidolina multiseptata Zone and to the Japanese Yabeina globosa Zone. This zone is considered equivalent to the Capitanian Stage at the top of the Guadalupian Series in southwestern North America. Morphological and faunal analyses of these North American Cordilleran species of Yabeina and Lepidolina and most of the associated species of schwagerinids (for example, Chusenella andersoni, C. atlinensis, and Schwagerina pavilionensis) suggest ages that range through the late Guadalupian. the highest zone of the Tethyan Midian lacks Yabeina and other neoschwagerinids and is based on the ammonoids Eoaraxoceras and Anderssonoceras. This zone is found in sediments of post-Capitanian (post-Guadalupian) age in northern Mexico.

Despite a rich and varied record, Mesozoic stalked crinoids are relatively rare in the Western Interior Seaway of North America compared to those found in Northern Europe. A unique example of Mesozoic stalked crinoid is described from cold methane seeps (hydrocarbon seep mounds also called “tepee buttes”) from the Upper Cretaceous (upper Campanian) of the Northern Great Plains of the United States; the first crinoids to be described from such an environment. The Late Cretaceous Western Interior Seaway has never before yielded any identifiable stalked crinoid remains. Nevertheless, there have been significant studies on both free living and stalked crinoids from other locations in the Upper Cretaceous of North America that provide a good basis for comparison. Lakotacrinus brezinai n. gen. n. sp. is characterized by a tapering homeomorphic column with through-going tubuli, lacking any attachment disc. The arms are unbranched and pinnulate, with muscular and syzygial articulations. The unique morphology of the column justifies the establishment of Lakotacrinidae new family. A new suborder Lakotacrinina n. subord., is also proposed as there exists no corresponding taxon within the Articulata that can accommodate all the characteristics of this new genus. This new crinoid shares many features with other members of the articulates, including bathycrinids, bourgueticrinids and guillecrinids within the Order Comatulida, as currently defined in the revised Treatise of Invertebrate Paleontology. Reconstructing the entire crinoid using hundreds of semi-articulated and disarticulated (well preserved) fossils, reveals a unique paleoecology and functional morphology specifically adapted to living within this hydrocarbon seep environment.

Agnostus acadicus Hartt (in Dawson, 1868) was the first agnostoid trilobite to be described from Middle Cambrian strata in North America. It was later designated the type species of Acadagnostus Kobayashi, 1939. The original description of A. acadicus was based on two specimens, a cephalon and a pygidium, which are illustrated for the first time with photographs. These are interpreted to represent separate species, each belonging to a different genus. The holotype cephalon is reassigned as Peronopsis acadica, which is judged to be a subjective senior synonym of Agnostus fallax Linnarsson, 1869, and several other species-group taxa. Consequently, Acadagnostus is suppressed as a subjective junior synonym of Peronopsis. Agnostus fallax is the type species of Axagnostus Laurie, 1990, which also is suppressed as a subjective junior synonym of Peronopsis. The pygidium on which the original description of A. acadicus was based is reassigned to Hypagnostus parvifrons (Linnarsson, 1869).

Peronopsis acadica, as emended, is a common, cosmopolitan agnostoid in open-marine lithofacies. It has an observed stratigraphic range from the Ptychagnostus praecurrens Interval-zone to the Ptychagnostus punctuosus Interval-zone.

New ornithischian remains reported here (MPEF-PV 3826) include two complete metatarsi with associated phalanges and caudal vertebrae, from the late Toarcian levels of the Cañadón Asfalto Formation. We conclude that these fossil remains represent a bipedal heterodontosaurid but lack diagnostic characters to identify them at the species level, although they probably represent remains of Manidens condorensis, known from the same locality. Histological features suggest a subadult ontogenetic stage for the individual. A cluster analysis based on pedal measurements identifies similarities of this specimen with heterodontosaurid taxa and the inclusion of the new material in a phylogenetic analysis with expanded character sampling on pedal remains confirms the described specimen as a heterodontosaurid. Finally, uncommon features of the digits (length proportions among nonungual phalanges of digit III, and claw features) are also quantitatively compared to several ornithischians, theropods, and birds, suggesting that this may represent a bipedal cursorial heterodontosaurid with gracile and grasping feet and long digits. In particular, the elongated non-terminal pedal phalanges and morphology of digit III resemble features present in arboreal birds, a unique condition found so far among ornithischians.

A new and unusually well preserved bivalve fauna of Late Ordovician age was recovered from pebbles within the Late Ashgill (Hirnantian) glacigenic diamictite of the Don Braulio Formation, in the Argentine Precordillera. According to the associated brachiopods and the presence of graptolites of the bicornis Zone in the matrix of the diamictite, an early Caradoc age is accepted for the bivalve fauna. The clasts contain bivalve molluscs representing nine genera, of which seven are new. Identified taxa are the following: Praenucula sp., Cuyopsis symmetricus new genus and species, Villicumia canteraensis new genus and species, Trigonoconcha acuta new genus and species, Concavodonta ovalis new species, Hemiconcavodonta minuta new genus and species, Hemiconcavodonta sp., Emiliania cuerdae new genus and species, and Concavoleda braulense new genus and species. Two new subfamilies are proposed: Praenuculinae and Concavodontinae. The genera Praenucula Pfab, Cuyopsis new genus, Villicumia new genus, and Trigonoconcha new genus are included in the new subfamily Praenuculinae. The genera Concavodonta Babin and Melou, Hemiconcavodonta new genus, and Emiliania new genus are included in the new subfamily Concavodontinae.

Intermediate morphologies of a new fossil crinoid shed light on the pathway by which crinoids acquired their distinctive arms. Apomorphies originating deep in echinoderm history among early nonblastozoan pentaradiate echinoderms distinguish Tremadocian (earliest Ordovician) crinoid arms from later taxa. The brachial series is separated from the ambulacra, part of the axial skeleton, by lateral plate fields. Cover plates are arrayed in two tiers, and floor plates expressed podial basins and pores. Later during the Early Ordovician, floor plates contacted and nestled into brachials, then were unexpressed as stereom elements entirely and cover plates were reduced to a single tier. Incorporation of these events into a parsimony analysis supports crinoid origin deep in echinoderm history separate from blastozoans (eocrinoids, ‘cystoids’). Arm morphology is exceptionally well-preserved in the late Tremadocian to early Floian Athenacrinus broweri new genus new species. Character analysis supports a hypothesis that this taxon originated early within in the disparid clade. Athenacrinus n. gen. (in Athenacrinidae new family) is the earliest-known crinoid to express what is commonly referred to as ‘compound’ or ‘biradial’ morphology. This terminology is misleading in that no evidence for implied fusion or fission of radials exists, rather it is suggested that this condition arose through disproportionate growth.

UUID: http://zoobank.org/b383e039-3298-4472-a7e3-e81684f87cfe

Modern computer-aided techniques foster the availability and quality of 3D visualization and reconstruction of extinct and extant species. Moreover, animated sequences of locomotion and other movements find their way into motion pictures and documentary films, but also gain attraction in science. While movement analysis is well advanced in vertebrates, particularly in mammals and birds, analyses in arthropods, with their much higher variability regarding general anatomy and size, are still in their infancies and restricted to a few laboratory species. These restrictions and deficient understanding of terrestrial arthropod locomotion in general impedes sensible reconstruction of movements in those species that are not directly observable (e.g., extinct and cryptic species). Since shortcomings like over-simplified approaches to simulate arthropod locomotion became obvious recently, in this review we provide insight into physical, morphological, physiological, behavioral, and ecological constraints, which are essential for sensible reconstructions of terrestrial arthropod locomotion. Such concerted consideration along with sensible evaluations of stability and efficiency requirements can pave the way to realistic assessment of leg coordination and body dynamics.

Multielement taxonomy and shape analysis have led to substantial revisions in the taxonomic concepts of 13 Frasnian species of Palmatolepis, which previously have been based largely on visual discrimination of the Pa elements. Septimembrate apparatuses have been recognized in three species and diagnostic Pb elements are associated with the Pa elements of eight others. The multielement reconstructions thus derived provide the a priori classification that is tested by the canonical variate analysis of the outlines of the Pa elements. The outlines are digitized from a TV image and quantified by calculating mean tangent angles within a specified number of intervals between landmarks. The mean tangent angles for each interval are the variables used in the canonical variate analysis. In a series of comparisons limited to three species each, all 13 species separate into isolated clusters that are completely congruent with the a priori groups based, with two exceptions, on multielement taxonomy. Thus, shape analysis provides a rigorous separation of closely similar species that have been difficult to distinguish by visual discrimination of the Pa elements. Shape analysis is treated herein as an integral part of the systematic descriptions. Newly described species are P. bohemica, P. boogaardi, P. luscarensis, and P. muelleri. The new taxonomic concepts lead to significant revisions in the biostratigraphic ranges of a number of species of Palmatolepis involved in the zonation and graphic correlation of the Frasnian Stage.

A new family, Bimuroporidae, is proposed for a clade of Ordovician trepostome bryozoans. The family is united by several characteristics, including a zooidal ontogenetic progression from mesozooid to autozooid and an integrate wall structure. Discriminant and cladistic analyses of colonies from the Ordovician Simpson Group outcropping in the Arbuckle Mountains and Criner Hills of south-central Oklahoma permit the recognition of eight species belonging to this family. Four species assigned to the new genus Bimuropora are described: B. dubia (Loeblich), B. pollaphragmata n. sp., B. conferta (Coryell), and B. winchelli (Ulrich), as well as four species assigned to the genus Champlainopora Ross: C. chazyensis (Ross), C. ramusculus n. sp., C. pachymura (Loeblich), and C. arbucklensis n. sp.