bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dizygocrinus: Mississippian camerate crinoid (Echinodermata) from the midcontinental United States
Authors: Ausich William I. , Kammer Thomas W. 
Published: August 2016

The Mississippian crinoid genusDizygocrinusis revised, and the phylogeny is inferred. Eleven species are recognized, includingD. biturbinatus(Hall),D. indianaensis(Lyon and Casseday),D. caroli(Hall),D. whitei(Wachsmuth and Springer),D. originarius(Wachsmuth and Springer),D. montgomeryensis(Worthen),D. gorbyi(Miller),D. venustus(Miller),D. peculiaris(Miller and Gurley),D. mutabilis(Wachsmuth and Springer), andD. cantonensis(Wachsmuth and Springer). Nomenclatoral revisions include recognition ofD. gorbyiandD. peculiarisas valid species and designation of the following as junior synonyms:D. calvus, D. crawfordsvillensis, D. intermedius, D. mediocris, andD. somersetensis. Dizygocrinusis now recognized from both the late Osagean and Meramecian on both the eastern and western margins of the Illinois Basin.Dizygocrinusis first recognized virtually simultaneously on both the eastern and western margins of the Illinois Basin. Migration proceeded in both directions, but was most common later in the history of the genus. The principal radiation on the western basin margin was among species with generally smooth aboral cup plates, whereas on the eastern margin sculptured species account for the principal species radiation.
Gastropods (Mollusca) from the Imo Formation (Mississippian, Chesterian) of north-central Arkansas
Authors: Jeffery D. L. , Hoare R. D. , Mapes R. H. , Brown C. J. 
Published: August 2016

The Chesterian (Upper Mississippian) Imo Formation in north-central Arkansas contains an abundant, diverse, and well-preserved gastropod fauna, comprising 35 species referrable to 21 genera and subgenera. Bellerophontaceans and pleurotomariaceans show the greatest species diversity. New taxa proposed include:Euphemites chesterensis, E. whirligigi, Retispira yochelsoni, Patellilabia rhombadella, P. sulcata, Straparollus (Euomphalus) konobasis, S. (E.) variabilis, Trepospira (Angyomphalus) desultoria, Glabrocingulum (Glabrocingulum) parasolum, G. (G.) parvanodum, G. (G.) coronulum, Naticopsis (Marmolatella) macgordoni, N. (M.) imoensis, Globozyga mediocris, and Girtyspira microspirula.Relicts of color patterns are present on four taxa. Repair of broken shells is common. Borings of acrothoracic barnacles and possibly that of a gastropod are present. Coprolites with gastropods attached may indicate a coprophagous habit, only grazing on the algae and bacteria growing on the coprolite, or may just be a circumstance of preservation.
Re-evaluation of the Palasteriscidae Gregory, 1900, and the early phylogeny of the Asteroidea (Echinodermata)
Authors: Blake Daniel B. 
Published: August 2016

Foliaster transversusn. gen. and sp. (Echinodermata: Asteroidea) is assigned to the Ordovician through Devonian family Palasteriscidae; the other genera included in the family arePalasteriscusandPlatanaster. Platanasteris redescribed; both it andFoliasterare thought to have been suspension feeders that extended their arms into the water column. Ampullar basins in both were external; there are no podial pores. The strongly petaloid arm ofFoliasterwith widely separated podial basins is unique.Two competing phylogenies have been offered for the origin of stelleroids, one treating edrioasteroids as ancestral, the other favoring crinoids. In the latter hypothesis, the Palasteriscidae is the primitive asteroid family, andPlatanasteris an example of the first true asteroids. Both hypotheses are here considered to lack adequate support; stelleroid origins remain problematic.
The order Fenestrata (Bryozoa) of the Toroweap Formation (Permian), southern Nevada
Authors: Mccolloch Miriam E. , Gilmour Ernest H. , Snyder Edward M. 
Published: August 2016

Recently developed analytical procedures for meshwork fenestrate and pinnate bryozoans made it possible to recognize two Russian species in the Toroweap Formation of southern Nevada. This analysis separates zoarial and zooecial features and emphasizes the three-dimensional form and size of the zooecial chamber as well as accessory features. In this investigation, these analytical procedures are successful even when specimens are fragmented and embedded in a hard rock matrix.The bryozoans in the Toroweap Formation in this study were found to be more similar to Permian species of the Russian platform than to species described in earlier North American Permian studies. Five species of fenestrate bryozoans are present in the Toroweap Formation. Wjatkella permiana Morozova, 1970, and Polypora sargaensis Trizna, 1948, originally described in Russia, are recognized in the Toroweap. Three new species, Penniretepora oppositus n. sp., Septopora bilateralis n. sp., and Reteporidra anaphora n. sp., are present and, along with the Russian species, are described in this paper.The local range zones of the five species of fenestrates were identified in three measured sections. Penniretepora oppositus and Septopora bilateralis are present throughout the three sections; Reteporidra anaphora is present in the lower two-thirds of the three sections; Wjatkella permiana is present in the middle parts of the three sections; and Polypora sargaensis is present in the upper parts of the three sections. Concurrent range zones, based on ramose bryozoans, were previously identified in two of the three sections and, using the distribution of the fenestrates in these two sections, four of the five concurrent range zones were recognized in the third section.
Ontogenetic development of Pa element cup microsculpture in Lochriea commutata (Branson and Mehl, 1941) (Conodonta, Carboniferous): taxonomic implications
Authors: von Bitter Peter H. , Norby Rodney D. 
Published: August 2016

Cup nodes on Lochriea commutata Pa elements bear microsculpture fields composed of polygonal microsculpture. As Pa elements grow larger, the cup nodes and their microsculpture fields increase in size during early to middle growth. With subsequent growth, cup nodes may broaden transversely, split, fuse, or cease to broaden; similarly, their microsculpture fields may increase in size, split, or disappear as the element gets larger. The loss of microsculpture fields results in the loss of polygonal microsculpture.The presence of polygonal microsculpture on the cup nodes of Pa elements of the holotype of Lochriea montanaensis Scott, 1942, on topotype Pa elements of L. commutata (Branson and Mehl, 1941), as well as on L. commutata Pa elements from diverse localities, suggests that this micromorphological feature cannot be used to distinguish them. Instead, these similarities support the practice of treating L. montanaensis as a junior synonym of L. commutata. The fact that cup node, microsculpture field, and polygonal microsculpture development are closely related to growth and ontogeny and are variable in the larger growth stages suggests that these morphological features should be used with caution in taxonomy. This lack of reliability contrasts with the taxonomic utility of pustulose micrornamentation on the homeomorphic Pa elements of the Permian genus Sweetognathus.
Pennsylvanian bairdiidae (Ostracoda) from the Appalachian basin
Authors: Hoare R. D. , Svitko J. L. , Sturgeon M. T. 
Published: August 2016

Bairdiid ostracodes are commonly present in the Pennsylvanian marine zones in the Appalachian basin. Thirty-one taxa are recognized representing the genera Bairdia McCoy, 1844; Orthobairdia Sohn, 1960; Cryptobairdia Sohn, 1960; Rectobairdia Sohn, 1960; Bairdiolites Croneis and Gale, 1939; and Bairdiacypris Bradfield, 1935. Two questionable bairdiid genera, Entmema new genus and Hastacypris Croneis and Gutke, 1939, are included. Seven new taxa, Bairdia cuspidis, Rectobairdia absidata, R. apiculata, R. levis, R. sohni, Entmena distenta, and Hastacypris acutula, are described. Fabalicypris Cooper, 1946, is considered a junior synonym of Bairdiacypris Bradfield, 1935.The diversity of bairdiids is significantly lower in the Appalachian basin than in the Eastern Interior and Western Interior basins.
An elasmobranch assemblage from the terrestrial-marine transitional Lethbridge Coal Zone (Dinosaur Park Formation: Upper Campanian), Alberta, Canada
Authors: Beavan Neil R. , Russell Anthony P. 
Published: August 2016

The change in depositional environments observed in the Cretaceous (Upper Campanian) strata in the region of Dinosaur Provincial Park, Alberta, from the proximal coastal plain deposits of the Oldman Formation to the lowland coastal plain deposits of the Dinosaur Park Formation, reveals an associated change in faunal composition. An assemblage collected from a microvertebrate site in the paralic deposits of the Lethbridge Coal Zone (uppermost Dinosaur Park Formation) reflects an increasing marine influence. Elasmobranch (sharks and rays) remains are the most abundant, both in terms of number of overall taxa and number of elements, and they are the best-preserved specimens. However, several brackish-water-tolerant osteichthyan taxa, and four reptile taxa (two marine and two terrestrial), were also recovered, although they exhibited evidence of extensive taphonomic reworking.The elasmobranch fauna collected from the Dinosaur Park locality is uncommon for vertebrate microfossil assemblages in the Dinosaur Park Formation of Alberta and in equivalent beds in Montana. Seven of the 10 taxa collected from this site [Cretorectolobus olsoniCase, 1978;Eucrossorhinus microcuspidatusCase, 1978;Odontaspis aculeatus(Cappetta and Case, 1975);Archaeolamna kopingensis judithensisSiverson, 1992;Protoplatyrhina renaeCase, 1978;Ischyrhiza miraLeidy, 1856; andPtychotrygon blainensisCase, 1978] are recorded for the first time from the uppermost section of the Judith River Group in Alberta;Carcharias steineri(Case, 1987), represents the first occurrence within the upper Judith River Group from either Alberta or Montana.
Shell shape plasticity in Late Pennsylvanian myalinids (Bivalvia)
Authors: Hickey David R. 
Published: August 2016

Analyses of shell shape variation in epifaunal and semi-infaunal myalinids from the LaSalle “cyclothem” attest to the extensive shape plasticity of some Late Pennsylvanian myalinids. Mean shell shapes differ significantly within and among species across three nearshore facies. Discriminant analyses of Fourier biometric data categorized by taxonomic, populational (habitat), life-mode, and “multi-species habitat assemblage”” discriminant groups reveal patterns of shape change and variation across an inferred environmental stress gradient in addition to taxonomic and life-mode shape differences. Fourier harmonic data are good indicators of shape differences between epifaunal and semi-infaunal life modes. Mean shapes of epifaunal species vary among habitats. Within-habitat shell shape convergence occurred between Myalina glossoidea and M. (Orthomyalina) slocomi. Interpopulational shape divergence occurred among all populations of M. (Orthomyalina) slocomi, M. glossoidea, and M. wyomingensis. Within-species variation among habitats produced significant mean shape differences among each of three “multi-species habitat assemblages.” Results indicate that a portion of the variation is of ecophenotypic origin.Mean interspecific shape differences reflect internal functional organization and life modes. Intraspecific shape differences among epifaunal species could reflect physical and biotic habitat variables. Several harmonic amplitudes vary in concert with inferred environmental variation among habitats. Although biologic interpretation of harmonic data is problematic, parallel trends in fifth harmonic amplitudes of epifaunal species mirror inferred differences in water turbulence among habitats and could reflect shape variation related to byssal attachment.Stress gradient trends in intraspecific shape variability cannot be collectively explained by either of the antithetical stability-diversity-variation hypotheses. Each species exhibits a different nonmonotonic trend. Maximal levels of intraspecific variation within each species occurred within different habitats. Within-species differences in levels of variation could result from genetic variation among populations as well as ecophenotypic influences. Comparative studies of ontogenetic shape change between valves of individuals, among individuals, and among populations are necessary to determine the relative influence of environmental variables on shape variation and evolutionary significance of phenotypic plasticity.
Miocene rhinoceroses from the Texas Gulf Coastal Plain
Authors: Prothero Donald R. , Manning Earl M. 
Published: August 2016

Four species of rhinoceros occur together in the Barstovian (middle Miocene) faunas of southeast Texas, a unique situation in the Miocene of North America. Two are assigned to normal contemporary High Plains species ofAphelopsandTeleoceras, and two to dwarf species ofPeracerasandTeleoceras. The dwarfPeracerasis a new species,P. hessei. The dwarfTeleocerasis assigned to Leidy's (1865) species “Rhinoceros”meridianus, previously referred toAphelops. “Aphelops”profectusis here reassigned toPeraceras.The late Arikareean (early Miocene) Derrick Farm rhino, erroneously referred to “Caenopus premitis” by Wood and Wood (1937), is here referred toMenoceras arikarense. Menoceras barbouriis reported from the early Hemingfordian (early Miocene) Garvin Gully local fauna of southeast Texas. The rhinos from the early Clarendonian Lapara Creek Fauna are tentatively referred toTeleocerascf.major.The three common genera of middle late Miocene rhinoceroses of North America (Aphelops, Peraceras, Teleoceras) are rediagnosed.AphelopsandPeracerasare more closely related to the EurasianAceratheriumandChilotherium(all four together forming the Aceratheriinae) than they are to the AmericanTeleoceras. Contrary to Heissig (1973),Teleocerasis more closely related to the living rhinoceroses and their kin (together forming the Rhinocerotini) than it is to the Aceratheriinae.
Invertebrate paleoecology of the Upper Cliff coal interval (Pennsylvanian), Plateau Coal Field, northern Alabama
Authors: Gibson Michael A. , Gastaldo Robert A. 
Published: August 2016

The Upper Cliff coal interval (Early Pennsylvanian) of northern Alabama consists of sandstone, siltstone, shale, and coal deposited within a southwestward prograding deltaic complex as previously defined using paleobotanical and sedimentological evidence. The paleoecology of two invertebrate-bearing lithofacies was studied within this context. A lower shaley-siltstone lithofacies records the inundation of the Upper Cliff #1 peat-accumulating swamp/marsh by fresh-water influenced brackish to restricted marine deposits. The fauna is dominated by the inarticulate Orbiculoidea and the trace fossil Planolites. As inundation continued, an interdistributary bay developed. Diversity and abundance of taxa increased with the establishment of a molluscan dominated Pteronites-Pianolites assemblage. The assemblage consists of a low diversity and low abundance fauna of bivalves and trace fossils that suggest soft substrates with abundant organics.The overlying sandstone lithofacies consists of a basal shell-bed (Schizophoria zone) composed of rare indigenous Pteronites and Wilkingia and a transported component of open marine epifaunal brachiopods, gastropods, and trilobite fragments. The Schizophoria zone thins to the northeast, suggesting open marine conditions to the southwest. Directly above this bed, the fauna of the sandstone lithofacies is composed entirely of Zoophycos. Higher in the section, rare Pteronites and Wilkingia occur, thus this lithofacies preserves a Wilkingia-Pteronites-Zoophycos assemblage of low abundance and diversity reflecting mobile organic-poor substrates. The sandstone lithofacies is interpreted as a migrating sand body with a basal shell-bed, initially formed probably as a result of storm activity.
Distribution of Tylothyris (Brachiopoda) and its occurrence in the Traverse Group (Middle Devonian) of Michigan
Authors: Rogers Frederick S. , Pitrat Charles W. 
Published: August 2016

The septate, lamellose, spiriferacean brachiopod genus Tylothyris North, 1920, is considered to be a delthyridid of the subfamily Tylothyridinae Carter, 1972. Herein, the diagnosis of the Tylothyridinae is emended to include forms with micro-ornament, and with a myophragm or median septum on the floor of the pedicle valve.For the first time, Tylothyris is formally reported from the Traverse Group rocks of Michigan, Givetian through early Frasnian in age. Two species of the genus occur in the Traverse Group. The first, T. subvaricosa (Hall and Whitfield, 1872), previously described by Stainbrook (1943) from the Cedar Valley Limestone of Iowa, is also known from the Milwaukee Formation of Wisconsin and the Mineola Limestone of Missouri. Tylothyris randalia Stainbrook, 1943, also from the Cedar Valley Limestone, is considered to be synonymous with T. subvaricosa. In the Traverse Group, T. subvaricosa occurs in the Bell Shale, Rockport Quarry Limestone, Ferron Point Formation, Genshaw Formation, Alpena Limestone, Gravel Point Formation, Norway Point Formation, and Potter Farm Formation. The second species, T. rockportensis n. sp., occurs only in the Rockport Quarry Limestone, and appears to be endemic to the Michigan Basin.Tylothyris is considered to have originated in the Illinois area during the late Eifelian, then to have migrated to the Michigan area by the early Givetian. With the onset of Taghanic Onlap during the late Givetian, the genus dispersed from its Illinois–Michigan area of origin, becoming distributed across much of North America during the Frasnian and Famennian, and becoming essentially cosmopolitan in distribution during the Tournaisian. Tylothyris apparently became extinct by the end of the Visean.
Enrolled trilobites from the Alden Pyrite Bed, Ledyard Shale (Middle Devonian) of western New York
Authors: Babcock Loren E. , Speyer Stephen E. 
Published: August 2016

Although enrollment has long been recognized as an important, perhaps advantageous, life posture in certain trilobites, some aspects of this phenomenon are poorly understood. Taphonomic evidence indicates that the preservation of enrolled trilobites is a two-stage process involving: 1) factors that evoked enrollment; and 2) depositional and geochemical factors that resulted in preservation of the trilobites in an enrolled condition.The Alden Pyrite Bed, Ledyard Shale Member, Ludlowville Formation (Middle Devonian, Givetian) of western New York, a well-known stratigraphic marker bed, is formally described herein. This bed yields an extraordinary number of enrolled phacopine trilobites. This study suggests that trilobites, like certain modern arthropods, enrolled in response to inhospitable conditions, including environmental toxicity and/or rapid sediment influx. Frequency of occurrence data from the Alden Pyrite Bed and underlying and overlying beds of the Ledyard Shale indicate that the trilobitesGreenops boothi(Green) andPhacops rana(Green) both enrolled in response to adverse conditions at the sediment-water interface. Prolonged adversity compelled the trilobites to remain, and eventually die, in an enrolled state. Rapid and deep burial within a fine-grained sediment precluded scavenger dismemberment and favored geochemical conditions which culminated in pyritization and preservation.
Population genetics of four species of Ordovician bryozoans: stereology and jackknifed analysis of variance
Authors: Pachut Joseph F. 
Published: August 2016

Collections of four Ordovician bryozoan species from habitats of differing levels of taxonomic diversity were examined in order to assess the effect of environmental conditions on intraspecific and interspecific morphologic patterns. Up to 20 morphometric characteristics were measured for each species from populations in both high-diversity and low-diversity settings. Character means and the levels of character variability differ between populations in different diversity zones. Across species, mean character values differ significantly in 41 percent of the total comparisons, permitting intraspecific and interspecific multivariate discrimination of populations from the two diversity zones.The partitioning of clonal morphologic variability into within-colony (nonheritable) and among-colony (potentially heritable) components reveals that habitat conditions favoring high diversities appear to promote a greater proportion of potentially heritable genetic variation both within- and among-species than do low-diversity settings wherein a larger percentage of variation is ecophenotypic, or nonheritable, plasticity. Although the actual percentages vary from species to species, this pattern is obtained for representatives of four different trepostome bryozoan families and therefore is robust. Variability of this sort, if unrecognized, could lead to taxonomic oversplitting along ecologic gradients. These local, facultative adjustments to environmental conditions may be indicative of processes involved in the reactions of populations to selective pressures.Analyses such as this, coupled with examinations of character covariances, may permit the recognition not only of environmentally-induced morphologic plasticity and the proportions of potentially heritable and nonheritable variability, but also provide evidence for intraspecific changes in the rates and timing of developmental events (i.e., across-population or facultative heterochrony).
Format for submittal of manuscripts to the

Journal of Paleontology
Authors: Hoare R. D. , Steinker D. C. 
Published: August 2016

This short paper is prepared to help potential authors prepare manuscripts in the correct format for submission to the Journal. Correct preparation greatly speeds the editorial process and makes for less revision by the author.The abstract should be relatively short, concise, and informative, giving pertinent details of the research and conclusions reached. All new taxa should be itemized within it. Do not use innocuous statements such as “will be discussed herein.” References to literature are not to be included unless essential. Notes do not have abstracts.