Two new cirroidean gastropod genera, Alaskiella (family Porcelliidae) and Alaskacirrus (family Cirridae), from the Emsian (late Early Devonian) of west-central Alaska (Medfra B-4 quadrangle) are described. The shell of Alaskiella medfraensis new genus and species exhibits inclined heterostrophic coiling. This shell character is known among other members of the subclass Archaeogastropoda, but is recorded for the first time within members of the superfamily Cirroidea. Inclined heterostrophic coiling of the shell was probably developed independently in several different groups of the subclass Archaeogastropoda. The new genus Alaskacirrus, represented by Alaskacirrus bandeli new species, is the oldest and only known Paleozoic member of the family Cirridae. This suggests that the family Cirridae was separated from the family Porcelliidae since at least Early Devonian time and that it most probably developed from the subfamily Agnesiinae of the family Porcelliidae. Thus, the stratigraphic range of the family Cirridae is at least from Lower Devonian to Cretaceous, an interval of about 350 million years.

A study of the Upper Ordovician trepostomate bryozoans belonging to the families Amplexoporidae and Monticuliporidae, from the eastern Anti-Atlas of Morocco, is presented here. They occur in the marly to fine-grained limestone, intermediate unit of the Khabt-el-Hajar Formation, late Katian in age, representing outer-ramp depositional environments. They inhabited the highest paleolatitude known for a bryozoan fauna during the Ordovician, estimated at more than 65–70ºS. A total of 11 species of the genera Anaphragma, Atactoporella, Homotrypa, Monotrypa, Monticulipora, and Prasopora are described. Three species are already known from the equatorial-tropical paleocontinents of Baltica, Laurentia, and Siberia: Anaphragma mirabile, Monotrypa jewensis, and Prasopora falesi. Four new taxa are described:Anaphragma undulata, Atactoporella moroccoensis, Monticulipora globulata, and Monticulipora irregularis.

The two species of Anaphragma and the one of Atactoporella display significantly larger zoarial sizes than congeneric species, representing gigantism among bryozoans. Polar gigantism is rejected for the two species of Anaphragma as is gigantism related to photosynthetic endosymbionts. An alternative proposal for their giant size is their long zoarial life span due to their well-balanced, robust branching form, with a relatively wide basal supporting surface, adapted to unconsolidated substrates in environments below wave base. Their great stability in outer-ramp environments, with infrequent storms, would allow the zoaria to grow for an extended time and reach large sizes before being overturned and buried. Atactoporella moroccoensis, has both zoaria and zooecia gigantic, suggesting a hypothesis of polar gigantism.

A series of small road cuts of lower Boyle Formation (Middle Devonian: Givetian) near Waco, Kentucky, has produced numerous specimens of three blastozoan clades, including both “anachronistic” diploporan and rhombiferan “cystoids” and relatively advanced Granatocrinid blastoids. This unusual assemblage occurs within a basal grainstone unit of the Boyle Limestone, apparently recording a local shoal deposit. Diploporans, the most abundant articulated echinoderms, are represented by a new protocrinitid species, Tristomiocystis globosus n. gen. and sp. Glyptocystitoid rhombiferans are represented by isolated thecal plates assignable to Callocystitidae. Three species of blastoids, all previously undescribed, include numerous thecae of the schizoblastid Hydroblastus hendyi n. gen. and sp., the rare nucleocrinid Nucleocrinus bosei n. sp., and an enigmatic troosticrinid radial. The blastoid Nucleocrinus is typical for the age; however, the callocystitid, schizoblastid, and protocrinitid are not. Hydroblastus is the oldest known schizoblastid. Middle and Upper Devonian callocystitids have been previously reported only from Iowa and Michigan USA with unpublished reports from Missouri USA and the Northwest Territories, Canada. This occurrence is thus the first report of a Middle Devonian rhombiferan from the Appalachian foreland basin. Tristomiocystis is the first known protocrinitid in North America and the only protocrinitid younger than Late Ordovician. This occurrence thus represents a range extension of nearly 50 million years for protocrinids. This extraordinary sample of echinoderms in a Middle Devonian limestone from a well-studied area of North America highlights the incompleteness of the known fossil record, at least in fragile organisms such as echinoderms.

The extant irregular echinoids Echinoneus cyclostomus Leske and Brissus unicolor (Leske) are reported from the middle Pleistocene of Barbados. The moderately robust E. cyclostomus is well-preserved, while B. unicolor, which had a thin test in life, occurs as an internal mold. The holectypoid E. cyclostomus sensu lato occurs in fossiliferous deposits of Upper Oligocene to Pleistocene age in the Antillean region, showing remarkably little overall variation in test shape during this period. Similarly, gross morphological features of Recent B. unicolor are not dissimilar to those seen in some Caribbean species from the Paleogene, such as B. sp. cf. B. unicolor from the Middle Eocene of Jamaica. Superior fossil specimens will be required to determine if certain fossil species within these genera are valid. This analysis supports the observation that many taxa of the modern Antillean, shallow-water echinoid fauna have essentially persisted within the region since at least the Oligocene.

The earliest fossil gray whale (Eschrichtius) from the eastern North Pacific is reported from the Lower Pleistocene Rio Dell Formation of Humboldt County, Northern California. This specimen, a tympanic bulla and posterior process, is identical in morphology to extant Eschrichtius robustus and differs from Pliocene Eschrichtius sp. from the western North Pacific (Japan). Thus, it suggests that the modern bulla morphology of the gray whale had been acquired by the Early Pleistocene. The absence of fossil Eschrichtius in the Pliocene of the eastern North Pacific may indicate that the extant gray whale lineage originated in the western North Pacific during the Pliocene before invading the eastern North Pacific during the Early Pleistocene. Further discoveries of Plio-Pleistocene gray whale fossils will help test this hypothesis and properly interpret the evolutionary history of eschrichtiid clade.

Three species of Yoderimyinae (Eomyidae: Rodentia) are recognized from the lower part of the White River Formation (early to medial Chadronian) in the Flagstaff Rim area, Wyoming. The new material allows an improved diagnosis for the subfamily. The enamel microstructure of Yoderimyinae supports its inclusion in the Eomyidae.

A new genus, Zemiodontomys, is established for Yoderimys burkei Black, and new material, including upper dentition, is referred to this species. This genus differs from Yoderimys in having higher crowned and more lophodont teeth and in lacking P3. A second new genus, Litoyoderimys, is established for Yoderimys lustrorum Wood, and a new species, L. auogoleus, is referred to the genus. This genus has lower crowned, more cuspate teeth than Yoderimys.

Through early and medial Chadronian time, evolution in yoderimyines includes the following morphologic transformations: increase in size; increase in crown height and lophodonty of cheek teeth; reduction of P3 (from double-rooted, to single-rooted, to absent); increase in relative size of P4 and p4; and increased longitudinal torsion of the mandible.

Although there is a generally accepted framework for the Permian marine biogeography of Australia, significant uncertainties remain concerning the temporal biogeographical changes closely related to the timing of Permian glacial–interglacial events. Several recent studies along these research lines demonstrate the importance of a reliable high-resolution biostratigraphical timescale for paleobiogeographical and paleoclimatic reconstructions. This paper provides, for the first time, a full taxonomic and biostratigraphical study of the brachiopod fauna from the Wasp Head Formation, southern Sydney Basin, southeastern Australia. The fauna is associated with deposits of the first Permian glacial interval suggested for eastern Australia. Three brachiopod assemblages are recognized. The lower and middle assemblages contain scarce brachiopods although associated bivalves are comparatively more common. Despite very low diversity and low abundance, these two brachiopod assemblages contain characteristic species of the Strophalosia concentrica and Strophalosia subcircularis brachiopod zones, both considered of late Asselian age. The third assemblage, occurring in the uppermost part of the formation, contains more brachiopods than bivalves and is referred to early Sakmarian in age. The species diversity and stratigraphic occurrences of the brachiopod assemblages in relation to sedimentary facies suggest that the lower two assemblages may represent an intra-glacial interval while the younger third assemblage, characterized by abundant occurrences of Trigonotreta and Tomiopsis species, accompanied by the bivalve Eurydesma, is more indicative of a post-glacial benthic marine fauna comparable to coeval brachiopod faunas found elsewhere in Gondwana.

We describe a new species of enigmatic stalked filter feeder, Siphusauctum lloydguntheri, from the middle Cambrian (Series 3, Stage 5) Antimony Canyon locality of the Spence Shale of northern Utah. The described specimen is the only one known from the Spence Shale, represents the first occurrence of Siphusauctum outside the Burgess Shale, and is only the second described species from the genus. Siphusauctum lloydguntheri n. sp. differs from S. gregarium O’Brien and Caron, 2012 in the shape of its calyx and the position of the digestive tract. The new species provides some additional information about the possible affinities of enigmatic stalked Cambrian filter feeders, as well as the taphonomic pathways that lead to preservation of Siphusauctum.

Bed-by-bed sampling of the lower portion of the Daye Formation at Gujiao, Guizhou Province, South China, yielded new Griesbachian–Dienerian (Induan, Early Triassic) ammonoid faunas showing a new regional Induan ammonoid succession. This biostratigraphic scheme includes in chronological order the late Griesbachian Ophiceras medium and Jieshaniceras guizhouense beds, and the middle Dienerian Ambites radiatus bed. The latter is recognized for the first time as a separate biozone in South China. Eight genera and 13 species are identified, including one new species, Mullericeras gujiaoense n. sp. The new data show that a relatively high level of ammonoid taxonomic richness occurred rather rapidly after the Permian/Triassic mass extinction in the late Griesbachian, echoing similar observations in other basins, such as in the Northern Indian Margin.

UUID: http://zoobank.org/a24a3387-f3dd-4da4-a134-84372352a63d

Spatiopora Ulrich, 1882 is a trepostome bryozoan that is found encrusting living orthoconic nautiloids in the Upper Ordovician (Katian) of North America, as do several other bryozoans. These epizoozoan bryozoans are characterized by possessing thin unilaminate zoaria with rows of elongate maculae, which may be monticulate and aligned coaxially to the host growth axis. These develop a distinctive linear shape in response to growing on a conical host, rather than as a response to channelized water flow along the host. Monticules increase in size and spacing adorally until a maximum inter-macular area is reached that results in a decline in surface water flow efficiency, and a new monticular line is inserted. Orthocones normally swam forward at lower velocities that enabled lophophore eversion and feeding, which would have been impossible at the higher speeds reached when the host jetted backwards during escape. Monticules reduced drag and turbulence acting on the orthocones which allowed for more efficient venting of bryozoan macular excurrents. Characteristic elliptical monticule growth continued even after death of the motile host. A Trypanites-bryozoan-orthoconic nautiloid association shows a complex biological and taphonomic relationship between these organisms.

Morphologic variation within and among populations of the common monobathrid camerate crinoid Agaricocrinus was investigated using multivariate and bivariate techniques for samples from 15 localities in the Lower Mississippian (late Osagean) Fort Payne Formation of south-central Kentucky and north-central Tennessee. Despite a wide range of variability, two morphotypes were distinguished at most localities in both autochthonous and allochthonous carbonate facies: Agaricocrinus americanus and the less common A. crassus. Morphologic characters that can be reliably used to separate these taxa include character of the anal area, width of the second primibrachial, and shape of the arm facets. Many other characters of calyx shape and plate proportions used previously for species recognition, such as depth of the basal concavity, height of the interbrachials, height of the tegmen, and number of arms, are widely variable within populations. Variation within species populations is ontogenetic, although a geographic component is recognized within A. crassus. The definition of A. crassus is emended to encompass a broader range of variation than heretofore realized. Eight species previously reported from the Fort Payne Formation are placed in synonymy: A. arcula, A. dissimilis, A. elegans, A. podagricus, A. ponderosus, A. profundus, and A. tugurium are junior synonyms of A. americanus. A. attenuata is a junior synonym of A. crassus.

The Mississippian crinoid genus Dizygocrinus is revised, and the phylogeny is inferred. Eleven species are recognized, including D. 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), and D. cantonensis (Wachsmuth and Springer). Nomenclatoral revisions include recognition of D. gorbyi and D. peculiaris as valid species and designation of the following as junior synonyms: D. calvus, D. crawfordsvillensis, D. intermedius, D. mediocris, and D. somersetensis. Dizygocrinus is now recognized from both the late Osagean and Meramecian on both the eastern and western margins of the Illinois Basin.

Dizygocrinus is 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.

Twelve fused clusters of conodont elements representing the apparatus of Belodina compressa (Branson and Mehl, 1933) were recovered from the Plattin Limestone (Turinian) near New London, Missouri, and Hanover, Iowa. These clusters show that the apparatus of B. compressa consisted of four morphologically distinct elements: eobelodiniform (M), compressiform (S1), grandiform (S2), and dispansiform (S3) elements. All four element types are also present in fused clusters of B. confluens Sweet, 1979, supporting the interpretation that Belodina had a quadrimembrate apparatus. The B. compressa clusters were recovered from pellet-rich wackestones that yielded relatively large and diverse conodont faunas, in which only the elements of B. compressa were fused. The elements of B. compressa present in the fused clusters may have been deposited in fecal pellets, where a higher concentration of calcium phosphate, combined with the relatively large surface area contacts between B. compressa elements, facilitated the fusing of these elements into clusters. These fused clusters provide the basis for interpretation of the apparatus architecture of Belodina.

Evaluation of previously undescribed collections of Late Triassic Gryphaea from the North American Cordillera increases the temporal range and geographic distribution of the genus. Gryphaea (Gryphaea) arcuataeformis Kiparisova, G. cf. G. (Gryphaea) keilhaui Böhm, and a new species, G. (Gryphaea) nevadensis, occur in lower Carnian to upper Norian strata from Alaska, British Columbia, Oregon, and Nevada. The distribution is mostly primary with respect to the Upper Triassic North American Craton, and requires long-distance larval dispersal along the latitude of far-eastern Panthalassa. Unlike most modern oysters, the distribution of these Triassic gryphaeids may have been restricted to cool and deeper water environments.

An early Carnian age of Gryphaea (Gryphaea) arcuataeformis places this species as the oldest known Gryphaea. When combined with late Carnian and Norian occurrences from the North and South American Cordillera, these data indicate that a low-latitude origin for the genus cannot be overlooked. Gryphaeids survived the end-Triassic extinction event presumably by living in refugia.

Fossil eggs of clam shrimps (Spinicaudata) are rare and little attention has been paid to the study of their shape and microstructures. Here, we report the discovery of exceptionally preserved three-dimensional eggs from numerous specimens of Eosestheria elliptica Chen, 1976 from the lacustrine Early Cretaceous Yixian Formation in western Liaoning, China. These three-dimensionally preserved fossil eggs display a spherical shape with smooth surface, part of the tertiary envelope, and possibly the first embryonic cuticle, which were previously unknown or ambiguous. The eggs are abundant and assumed to be attached to the exopod as in extant Spinicaudata. Moreover, the exceptional three-dimensional preservation and delicate preparation of slices of the eggs allowed us to document the microstructures and elemental composition of fossil eggs of clam shrimps from the Jehol Biota. Energy dispersive spectroscopy of the fossilized envelope revealed a calcium phosphate composition. However, the egg contents display two completely different elemental compositions. Some exhibit the same elemental composition as the envelope, whereas others has been replaced by alumino-silicate. The taphonomic process is also briefly discussed in this paper.

We have been processing organic-rich shale from the Carboniferous Luocheng Formation, Peoples Republic of China, for microcrinoids and microgastropods. Initial attempts to disaggregate the shale using standard techniques (e.g., chlorine bleach, Quaternary-O, paint thinner, Stoddard's solution) proved futile. Nothing worked on the mixed organic/clay matrix in which the fossils were entombed. One particularly frustrating evening, a television commercial, in which a large hair clog in a clear plastic drain pipe was dissolved, inspired us to purchase and try some drain cleaner for processing our samples. After reading numerous drain-cleaner labels, we selected Liquid-plumr® because it contained one of the strongest concentrations of sodium hypochlorite and sodium hydroxide easily available. We are not necessarily recommending Liquid-plumr® over other brands; however, some drain cleaners are nothing more than concentrated sulfuric acid, so careful scrutiny of the labels is recommended.

The first fly fossil discovered from the Upper Jurassic Talbragar Fish Bed in Australia is described and illustrated. Based on a single, well preserved wing, Calosargus (Calosargus) talbragarensis new species is assigned to the extinct brachyceran family Archisargidae. Wing morphology suggests a relationship between this extinct family and Stratiomyidae. The Archisargidae have so far only been found in China, Kazakhstan and Mongolia. Calosargus Mostovski, 1997 currently comprises seven species from the Callovian (late Middle Jurassic) of China and three species from the Oxfordian (early Upper Jurassic) of Kazakhstan. This oldest brachyceran fossil from Australia and first record of the Archisargidae in the southern hemisphere presents evidence that higher flies were present in this region in the Jurassic, when this group is thought to have commenced its diversification.

Environmental conditions affect both the character and variability of developmental patterns (=astogeny) within each of four species of Ordovician bryozoans. Regressions between pairs of stereological measurements for populations from both high-and low-diversity habitats differ significantly in 79 percent of all comparisons. Deviations from a rigid pattern of development, measured as dispersion from regression, were greater in species populations from low diversity settings in 77 percent of comparisons. Therefore, both developmental patterns and their variability differ intraspecifically along a diversity gradient in representatives of four bryozoan families. Additionally, dispersion values were larger in younger rather than older colonies in two species irrespective of diversity level, thus suggesting an age-related reduction in variation.

Changes in developmental trajectories indicate that colonies from low-diversity settings are generally paedomorphic relative to conspecific populations from high-diversity habitats. The heritability of these characters and developmental patterns, estimated using variance partitioning techniques, is greater in high-diversity associations. These findings suggest that character state modifications dependent upon astogeny, or a consequence of astogenetic modifications, are more heritable in high-diversity settings. However, if the environment can cause facultative heterochrony, the possibility of fixing such patterns in subsequent generations is increased, although the mechanism for accomplishing this is presently unknown.

Foliaster transversus n. gen. and sp. (Echinodermata: Asteroidea) is assigned to the Ordovician through Devonian family Palasteriscidae; the other genera included in the family are Palasteriscus and Platanaster. Platanaster is redescribed; both it and Foliaster are 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 of Foliaster with 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, and Platanaster is an example of the first true asteroids. Both hypotheses are here considered to lack adequate support; stelleroid origins remain problematic.

Yuknessia Walcott, 1919 recently was transferred from the green algae to the Phylum Hemichordata on the basis of new details observed for the type species, Y. simplex, from the Burgess Shale Formation (Cambrian Stage 5) of British Columbia. This has prompted reexamination of material attributed to Yuknessia from various Cambrian localities in South China. Findings preclude both a Yuknessia and a hemichordate affinity for all of the Chinese study material, and most of this material is formally transferred to Fuxianospira Chen and Zhou, 1997, a taxon common in the Chengjiang biota. Comparable material from the Cambrian Marjum, Wheeler, and Burgess Shale formations of North America is also assigned to Fuxianospira, and this reassignment expands both the paleogeographic and stratigraphic range of this taxon. All aspects of the study specimens, including details obtained from scanning electron microscopy, are consistent with an algal affinity, as proposed in the original descriptions of the Chinese material.