bluuebunny/crossref_metadata_2025 huggingface dataset:
New Late Ordovician (Early Caradoc) bivalves from the Sierra de Villicum (Argentine Precordillera)
Authors: Sánchez Teresa M.
Published: August 2016

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.
Decapod and stomatopod crustaceans from mass mortality Lagerstatten: Turonian (Cretaceous) of Colombia
Authors: Feldmann Rodney M. , Villamil Tomas , Kauffman Erle G.
Published: August 2016

Mass mortality surfaces and bioclastic lags in Turonian siliceous shales of the San Rafael and La Frontera formations in Colombia have yielded two species of decapod crustaceans,Opthalmoplax spinosusnew species andPinnotheres? species indeterminate, as well as one stomatopod,Sculdasp. All represent first records for the country. Remains of the swimming carcineretid crab,Opthalmoplax spinosus, in association with fish fragments and pelagic ammonites, cover mass mortality surfaces. The occurrence suggests that the high density living population of the crabs, exploiting abundant food resources in areas of topography-controlled upwelling, was periodically reduced catastrophically, perhaps by advection of toxic trace elements or by oxygen starvation. Two other taphofacies, characterized by current oriented appendage fragments and scattered skeletal elements represent normal accumulations of fossil material in the San Rafael and La Frontera formations.
Compaction-related deformation in Cambrian olenelloid trilobites and its implications for fossil morphometry
Authors: Webster Mark , Hughes Nigel C.
Published: August 2016

Morphometric analyses of silicified and nonsilicified (preserved in shale) specimens of the olenelloid trilobitesOlenellus(Olenellus)gilbertiMeek (inWhite, 1874) andNephrolenellus geniculatusPalmer, 1998, from the Lower Cambrian C-Shale Member of the Pioche Formation show that even well-preserved specimens in shales have undergone significant changes in lateral as well as vertical dimensions as a result of compaction. Analyses of cephalic landmarks show that in both species compaction causes posteriordirected collapse of the anterior lobe of the glabella, adaxial deformation of the ocular lobes, and abaxial and anterior splaying of genal regions. These shape changes are explicable in terms of observed exoskeletal fracture patterns. Landmarks show an increase in scatter around their ontogenetic trajectories that is generally proportional to the degree of lateral shift each landmark has undergone. Interspecific differences in compactional response may depend on the relative convexity of the cephalon.Olenellus(Olenellus)gilbertiis a low-convexity species and shows marked lateral shape change, particularly in the genal region.Nephrolenellus geniculatusis more convex and shows less severe lateral shape change. Landmarks of both species exhibit an average trebling of the degree of scatter around their average ontogenetic trajectories in compacted samples. Because even well-preserved specimens in shales differ in shape from their precompactional appearance, results of morphometric studies utilizing metric distances between landmarks in trilobites where compaction can be detected must be interpreted with caution.
The Devonian trilobite Cordania from Australia
Authors: Ebach Malte C. , Edgecombe Gregory D.
Published: August 2016

The genus Cordania Clarke, 1892, has been known from the Lower Devonian (Lochkovian-Pragian) of the Appalachian Province and apparently from the Lower-Middle Devonian of China. Probable Lochkovian strata of the Biddabirra Formation in the Amphitheatre Group from near Cobar, New South Wales, Australia, have yielded Cordania buicki new species, extending the range of the genus to eastern Australia. Cladistic analysis of Cordania identifies C. buicki as more closely related to species from Oklahoma than to a northern Appalachian grade.
Fossil fish nests from the Koobi Fora Formation (Plio-Pleistocene) of northern Kenya
Authors: Feibel Craig S.
Published: August 2016

Piscichnus brownii n. gen. and sp. is described from the Plio-Pleistocene Koobi Fora Formation of northern Kenya. The trace fossil is an unornamented, shallow, dish-shaped structure preserved in concave epirelief on sandstones. This structure is interpreted to result from the nest-excavating activities of fish.
Morphometric study of the genus Ancyrodelloides (Lower Devonian, conodonts), central Nevada
Authors: Murphy Michael A. , Cebecioglu M. Kemal
Published: August 2016

This paper presents a morphometric study of the conodont genus Ancyrodelloides. It is one of a series of such papers whose goal is to increase the precision of correlation within the Lower Devonian by refining the taxonomic basis of its biostratigraphic units. Ancyrodelloides species are confined to the delta Zone and may be used to divide it into three parts. Morphometrics verify the species rank of A. eleanorae, A. limbacarinatus, A. trigonicus, and A. transitans. Ancyrodelloides delta and A. omus are retained as species on qualitative grounds, but need larger samples for statistical evaluation. Ancyrodelloides asymmetricus and A. kutscheri are classified as varieties, but lack adequate samples.
Burrowed Phacops rana from the Moscow Formation of New York
Authors: Zell Paul D.
Published: August 2016

The trilobite Phacops rana has previously been documented in two life positions: horizontally outstretched and enrolled (Hall and Clarke, 1888). A specimen of Phacops rana was recovered in an unusual life position from the Windom Member of the Moscow Formation (Figure 1). It was collected from a borrow pit along Castle Hill Road, 1 km east of Earlville in Chenango County, New York. The trilobite appears to have burrowed tail first into the substrate, with only part of the cephalon and one or two thoracic segments exposed above the sediment surface. The orientation of the eyes indicate that the visual field was horizontal. The thorax angled into the substrate at an angle of approximately 50° from the horizontal, with the pygidium tilted dorsally relative to the thorax. Compaction effects appear to be slight. Because the specimen was found in situ, no doubt exists as to its orientation with respect to bedding. It is also evident from bedding plane surfaces that this trilobite had burrowed, and was not simply draped over an uneven substrate, as it intersects three bedding planes. There is no evidence of any object over which it could have been draped. No burrow trace, lining, or scratch marks are preserved. No other specimens of Phacops in this position have been reported.
Heliolitid corals of the Upper Silurian West Point Formation, Gaspé, Québec
Authors: Lee D.-J. , Noble J. P. A.
Published: August 2016

The heliolitid fauna of the Upper Silurian West Point Formation of southern Gaspé, Québec, Canada, consists of Propora tubulata (Lonsdale), Heliolites decipiens (McCoy), H. daintreei Nicholson and Etheridge, and Heliolites sp. cf. H. bohemicus Wentzel. All of these species are common in Europe, but are rare in North America. Heliolites sp. cf. H. bohemicus and H. daintreei are newly reported for North America. Very restricted facies occurrences, and presumed environmental preferences, of species such as P. tubulata and H. daintreei suggest that facies occurrences may be useful, along with conventional morphological criteria, in distinguishing species of heliolitid corals.
New late Oligocene echinoids from the central Western Cascades of Oregon
Authors: Linder Robert A. , Durham J. Wyatt , Orr William N.
Published: August 2016

The echinoidsSalenia cascadensisn. sp.,Stomechinus? dissimilarisn. sp.,Glyptocidarissp.,Arbacia abiquaensisn. sp.,Lytechinus baldwinin. sp.,Gagaria crenularisn. sp., andKewia marquamensisn. 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 forKewia, these occurrences mark a more northerly limit for these genera in the northeastern Pacific and add to their stratigraphic range.
Shelf-facies microfossils from the Uluksan Group (Proterozoic Bylot Supergroup), Baffin Island, Canada
Authors: Hofmann H. J. , Jackson G. D.
Published: August 2016

Coccoid and filamentous microfossils in the Borden Rift Basin on northwestern Baffin Island and western Bylot Island are reported from 14 localities at six general stratigraphic levels in the Society Cliffs Formation, and one in the Victor Bay Formation. At least seven of 12 fossiliferous Society Cliffs samples, and one of two Victor Bay samples, are from cherty dolostones formed in shallow restricted, peritidal evaporitic environments. The remaining six fossiliferous samples accumulated in somewhat deeper, less restricted waters. The assemblage is preserved in black chert nodules and layers and comprises 30 taxa, including the filamentous formsArchaeotrichion? sp.,Tenuofilum septatum, Eomycetopsis robusta, Siphonophycus inornatum, S. kestron, Rhicnonema antiquum, Brachypleganonsp.,Eomicrocoleussp.,Uluksanella baffinensisn. gen. and sp.,Talakania? sp., the coccoid taxaEosynechococcus medius, E. grandis, Archaeoellipsoides obesus, Sphaerophycus parvum, S. medium, Myxococcoides minor, M. grandis, Melasmatosphaeraspp.,Phanerosphaerops capitaneus, Palaeoanacystissp.,Tetraphycus hebeiensis, Eogloeocapsa bella, Gloeodiniopsis magna, G.sp. 1,G. mikros, Polybessurus bipartitus, Cymatiosphaera? sp., the fusiformEupoikilofusa? sp., and rare specimens of two unidentified and problematic taxa.
Stiptognathus new genus (Conodonta: Ibexian, Lower Ordovician), and the apparatus of Stiptognathus borealis (Repetski, 1982)
Authors: Ethington R. L. , Lehnert Oliver , Repetski J. E.
Published: August 2016

Collections from upper Ibexian (Tulean Stage) rocks of western United States, from the Canning Basin in western Australia, and from the Argentine Precordillera contain a seximembrate apparatus of multidenticulate conodonts whose elements have been included by authors in species of Prioniodus Pander, 1986, and Reutterodus Serpagli, 1974. The individual elements as well as the complete apparatus are not consistent with assignment of the species to either of these genera or to any other extant genus. A new generic name, Stiptognathus Ethington, Lehnert, and Repetski, is proposed with Reutterodus borealis Repetski, 1982, as type species. The apparatus consists of Pa, Pb, Sa-c, and M elements; the genus represents either the Prioniodontidae or the Periodontidae.
Stygina, Eobronteus(Ordovician Styginidae, Trilobita): Morphology, classification, and affinities of Illaenidae
Authors: Whittington Harry B.
Published: August 2016

The fulcrate thorax ofStyginahas the articulating furrow and a long articulating halfring, no pleural furrow, and the facetted outer portion of the pleura has the doublure terminating outside the fulcrum. In the type species the glabella is inflated and the axial furrows partially effaced; in other species inflation is not accompanied by such effacement. Distinctions between genera of Stygininae are based on cephalic characters, including the length (sag. and exs.) of the preglabellar area; the variability of these characters makes such distinctions difficult to define.Eobronteushas the forwardly-expanding glabella, three pairs of glabellar furrows, rostral plate and hypostome typical of Siluro-Devonian Scutelluinae. The relationship between the two subfamilies is shown by morphology and by ontogeny. It is doubted that Styginidae had an origin in common with Illaenidae; the characters suggesting a relationship betweenNileusand illaenids are explored. To improve the classification of Trilobita, the search for Cambrian ancestors of Ordovician families needs to be intensified, and characters of the entire axial region should be taken into account. The impendent condition of the hypostome is homeomorphic and is of less significance in classification than the natant and conterminant conditions. Effacement of axial furrows of the cephalon is a trend displayed in Stygininae, and is another homeomorphic character that is not a reliable guide to relationship.
New data on the genusDiadeloplaxHoare and Mapes, 1995
Authors: Hoare R. D. , Mapes R. H.
Published: August 2016

Calyptraea antiqua Howse (1848, 1858), based upon a plate from the Permian of England, was included in the Polyplacophora. King (1850) questioned this assignment sinceCalyptraeais a gastropod. Kirkby (1859) placedC. antiquus(Howse) in the genusChitonellusLamarck, 1819 and described two new species from the Permian of England,C. hancockianusandC. distortus. Kirkby and Young (1867) described another taxon,C. subantiquus, from the Carboniferous of Scotland. Branson (1948) questioned the assignment of these species to the Polyplacophora. Smith and Hoare (1987) rejected them from the class. Kirkby also included other specimens inChitonellus; these are now assigned to the polyplacophoranGlyptochitondeKoninck, 1883. Geinitz (1861) followed the assignment of Kirkby and recognized three species using Kirkby's (1859) illustrations.
Early Pliocene horses from late Pleistocene fluvial deposits, Gulf Coastal Plain, south Texas
Authors: Baskin Jon A.
Published: August 2016

Isolated teeth and post-cranial elements of fossil vertebrates were recovered from sand and gravel pits in valley fill and terrace deposits along the Nueces River in San Patricio and Nueces Counties, Texas. A log from the valley fill deposit has been radiocarbon dated at 13,230 ± 110 BP. The fauna is mixed and comprises typical late Pleistocene taxa and relatively abundant remains of early Pliocene (latest Hemphillian) horses. The latter group includes Astrohippus albidens (Mooser), Nannippus spp., Neohipparion eurystyle (Cope), and a derived species of either Calippus or Pseudhipparion. Many of these specimens show little or no evidence of abrasion, in spite of the fact that they may have been transported at least 12–25 km. The source beds for these early Pliocene horses are unknown, but the fossils were probably eroded from older, updip sediments of the upper Goliad Formation during a low stand of sea level at the end of the Pleistocene and deposited during the late Wisconsinan.
Spiraclavus nacoensis, a new species of clavate agelacrinitid edrioasteroid from central Arizona
Authors: Sumrall Colin D.
Published: August 2016

Twenty-four fragmentary specimens and numerous disarticulated plates of a new clavate agelacrinitid edrioasteroid were collected from the Middle Pennsylvanian Naco Formation in central Arizona. Spiraclavus nacoensis n. gen. and sp. is similar to Lepidodiscus laudoni (Bassler, 1936) and Discocystis kaskaskiensis (Hall, 1858), but differs in the direction of ambulacral curvature and in the number and arrangement of ambulacral cover plates. Numerous well-preserved, disarticulated plates allow a full description of plate morphologies from various parts of the theca. The entire oral surface is rigidly constructed of tessellate plates. Interlocking serrate sutures between successive floor plates add strength. Plate sutures in the flexible and telescoping portions of the theca (recumbent zone and pedunculate zone, respectively) are beveled, allowing considerable imbrication and potential for thecal extension.

The associated fauna indicates that the unit containing the edrioasteroids was deposited on an offshore, subtidal, marine carbonate shelf with occasional siliciclastic influxes. The specimens of Spiraclavus nacoensis were buried by siliciclastics, probably during storm events.
Phylloid algal microstructures enhanced by epifluorescence petrography
Authors: Dawson William C.
Published: August 2016

“Phylloid algae” (Pray and Wray, 1963, p. 209) are problematical fossils that occur profusely in Pennsylvanian carbonate microfacies in the United States (Wray, 1968) and many other parts of the world (Mamet, 1991). Taxonomic affinities of most phylloid alga are uncertain. The questionable affinities of phylloid algae and related paleoecologic problems have been summarized by Riding (1977), Wray (1979), and James et al. (1988) and will not, therefore, be repeated here. Our ability to establish probable taxonomic affinities of fossil calcareous algae is dependent largely upon the recognition of their internal microstructures. Because phylloid algae are very susceptible to dissolution and neomorphism, their original internal microstructures are rarely well preserved.
Macroscenella (Mollusca) from the Middle Ordovician of Wisconsin—a reinterpretation and reassignment
Authors: Yochelson Ellis L.
Published: August 2016

Description of two new specimens of Macroscenella superba (Billings) provides additional data on this rare, poorly known Paleozoic genus. Macroscenella was considered first to be a gastropod, then a monoplacophoran, and finally a coelenterate. Chondrophorine affinities for this form cannot be totally ruled out, but the new specimens increase the probability that it is a mollusk. If so, Macroscenella is more likely a patellacean gastropod than a member of any other group of the Mollusca, though evidence for placement within the Mollusca is equivocal; the interior of the specimens is not exposed and musculature is unknown. If the integument was a shell, it was thin.
Scanning electron microscopy study of Cretaceous brachiopods of the new family Praeargyrothecidae: Implications for megathyroid systematics and terebratulide phylogeny
Authors: Mackinnon D. I. , Smirnova T. N.
Published: August 2016

Four species of megathyrid brachiopods from the Lower Cretaceous (Berriasian) of Crimea, Ukraine, and one species of megathyrid from the lower Upper Cretaceous (Cenomanian) of England are reinvestigated using scanning electron microscopy. The species are variously assigned to one existing genus,PraeargyrothecaSmirnova (P. hexaplicata(Smirnova) andP. megatrema(J. de C. Sowerby)) and two new genera,Krimargyrotheca(K. concinna(Smirnova) andK. balkiin. gen. and n. sp.) andEvargyrotheca(E. alta(Smirnova)). Taxa are distinguished principally on differences in shell shape, plication, and, in particular, surface microornament. The shell microstructure of all five species is investigated with particular emphasis on endopunctation and microornament. Dental plates are present briefly early in ontogeny. Based on the possession of transient dental plates, a septalium, and conspicuous microornament,Praeargyrothecais removed from the family Megathyrididae and assigned, along with the two new genera, to a new family Praeargyrothecidae. Scanning electron microscopy study of loop development in both fossil and Recent terebratelloids and megathyrids supports a recent immunological study of living taxa from both groups that suggests that the two groups are not as closely linked phylogenetically as previously maintained. The family Megathyrididae is thus removed from the superfamily Terebratelloidea and assigned, along with the new family Praeargyrothecidae, to a new superfamily Megathyridoidea.
Systematics and paleoecology of Late Cambrian echinoderms from the western United States
Authors: Sumrall Colin D. , Sprinkle James , Guensburg Thomas E.
Published: August 2016

Although echinoderm debris is locally common, articulated specimens are rare in Late Cambrian rocks from the Great Basin and Rocky Mountains of the western United States and are mostly associated with hardgrounds. The fauna, including cornute stylophorans, trachelocrinid eocrinoids, solute homoiosteleans, and rare edrioasteroids, includes several members of the archaic Cambrian Evolutionary Fauna, which had already passed its maximum diversity for echinoderms. In addition to the low diversity, articulated specimen abundance is very low, averaging only about one-tenth that found in overlying Lower Ordovician units. The transition between the Cambrian and Paleozoic Evolutionary Faunas for echinoderms in North America apparently occurred rapidly very close to the Cambrian-Ordovician boundary, because no unequivocal examples of the Paleozoic fauna (such as crinoids, glyptocystitid rhombiferans, asteroids, or echinoids) were found in the Late Cambrian sections.

New taxa include several cothurnocystid stylophorans assigned to Acuticarpus delticus, new genus and species, Acuticarpus? republicensis, new species, and Archaeocothurnus goshutensis, new genus and species; Scotiaecystis? species, a poorly preserved cornute stylophoran with lamellipores; Minervaecystis? species, a fragmentary solute homoiostelean based on several steles; Tatonkacystis codyensis, new genus and species, a well-preserved trachelocrinid eocrinoid with five unbranched arms bearing numerous brachioles; an unnamed, poorly preserved, epispire-bearing eocrinoid; an unnamed, poorly preserved, globular eocrinoid? lacking epispires; and an unnamed, heavily weathered, edrioasterid edrioasteroid. Nearly all holdfasts found in these Upper Cambrian units are single-piece blastozoan types, probably belonging to trachelocrinid and other eocrinoids. Distinctive columnals and thecal plates of several additional undescribed eocrinoids and other echinoderms were locally abundant and are also described.
Referral of Miacis jepseni Guthrie to Oödectes Wortman, and an assessment of phylogenetic relationships among early Eocene Miacidae (Mammalia: Carnivora)
Authors: Heinrich Ronald E.
Published: August 2016

A phylogenetic analysis was conducted to address evolutionary relationships among the earliest members of the Miacidae (one of two early Cenozoic carnivoran families) and to ascertain the position of an ambiguous taxon, “Miacis” jepseni, with respect to the genera Miacis, Uintacyon, Vulpavus, Vassacyon, and Oödectes. The results of this analysis indicate that “Miacis” jepseni should be referred to the genus Oödectes, and both genus and currently included species are rediagnosed. The phylogenetic relationship of Oödectes to other miacids, and relationships among early Eocene miacids more generally, however, are less well resolved. Support is found for sister taxon relationships between Miacis and Vulpavus and between Uintacyon and Vassacyon, and it is suggested that this latter clade is the sister taxon to all other members of Miacidae.
Aspects of the postcranial skeleton of the Lower Permian lungfish, Gnathorhiza
Authors: Dalquest Walter W. , Kocurko M. John , Grimes John V.
Published: August 2016

A newly discovered locality of aestivation burrow casts containing the lungfish, Gnathorhiza serrata, is reported from the early Permian Arroyo Formation of Wilbarger County, north-central Texas. Remains preserved in the burrow casts provide sections of mummified Gnathorhiza and new information about the postcranial skeleton of this fish. Scales of Gnathorhiza resemble those of the modern lungfishes such as Lepidosiren in their microanatomy. No traces of paddle-like pectoral or pelvic fins were found and paired fins of Gnathorhiza may have resembled those of Lepidosiren. The axial skeleton and median fins of Gnathorhiza seem to resemble those of Lepidosiren except that the tail area and caudal fin of Gnathorhiza were stout and strong rather than slender and tapering. Gnathorhiza, which aestivated tail-down in its burrow, may have required a stout tail for support.
A window of opportunity: peering into a new century of paleontology
Authors: Kaesler Roger L.
Published: August 2016

I want to begin by thanking you for giving me the opportunity to serve as President of The Paleontological Society and especially for the boundless cooperation I have received from you, the members. Few scientific societies work as well as The Paleontological Society. Some societies function because of the dedication of a few fully committed members. Others rely on paid, professional staff to conduct the society's business. In contrast, the success of The Paleontological Society stems from the day-to-day enthusiasm for our roles and goals that is distributed uniformly across the membership. Holding this office has been a high privilege, and I am grateful to you for having selected me.
The youngest carpoid: occurrence, affinities, and life mode of a Pennsylvanian (Morrowan) mitrate from Oklahoma
Authors: Kolata Dennis R. , Frest Terrence J. , Mapes Royal H.
Published: August 2016

Abundant, well-preserved specimens of a new peltocystidan mitrate carpoid,Jaekelocarpus oklahomensisn. gen. and sp., have been discovered in the Pennsylvanian (Morrowan Series) Gene Autry Shale Member, Golf Course Formation, in southern Oklahoma. The new carpoid postdates the youngest previously known carpoids (Middle Devonian) by about 65 million years. It is characterized by a small (to 4 mm in length) globose theca composed of six plates: two large adaulacophorals, two large marginals, and two relatively small plates that frame the main thecal orifice. One of the plates at the orifice bears a single stout spine. The theca and plates that comprise the theca display a high degree of bilateral symmetry. In contrast, the styloid has an asymmetrical array of spines and blades.

We hypothesize that most mitrates, including this one, were adapted to an infaunal life mode. The streamlined, generally symmetrical body shape is an adaptation to moving on or through the substrate. Spines and blades on the lower surface of the styloid and proximal aulacophore are inferred to be adaptations for gripping the substrate as the animal pulled itself backwards (aulacophore first). The main thecal orifice opposite the aulacophore was the site of both mouth and anus. Evidence for a sluggish, epifaunal life mode in the cornute carpoids includes the typically flattened, asymmetrical body, the presence of downward projecting spines and knobs on the marginal thecal plates of many species, and the specialized thecal pores and slits that faced away from the substrate.
The genusSwiftopectenHertlein, 1936, (Bivalvia: Pectinidae) in the Tertiary of southern South America
Authors: Del Río Claudia J.
Published: August 2016

The presence ofSwiftopectenHertlein, 1936, in Patagonia (Argentina), a region situated in the southeastern extreme of the South American continent, is the oldest and southernmost fossil record of the genus. Furthermore, its occurrence during the Late Eocene in the circum-Antarctic region suggests that its origin was in the Southern Hemisphere; it has been known from Japan and the eastern Pacific, ranging from Miocene to Holocene (Moore, 1984).Swiftopecten iheringiinew species, from the Late Eocene-Early Miocene sedimentary sequence of Patagonia, is described and illustrated.
Isotelus (Trilobita) “hunting burrow” from Upper Ordovician strata, Ohio
Authors: Brandt Danita S. , Meyer David L. , Lask Peter B.
Published: August 2016

Recurring associations of the trilobite ichnogenus Rusophycus with various “worm” burrows suggest an interaction between the two tracemakers, specifically, capture of the worm by the trilobite. An exceptional ichnofossil from the Upper Ordovician of southwestern Ohio shows characters consistent with previously described “trilobite hunting burrows” from Cambrian and Silurian strata. Preserved in convex hyporelief is R. carleyi, attributable to the trilobite Isotelus, on which is superimposed the case of a worm burrow of the ichnogenus Palaeophycus. The cast of the worm burrow appears to have been truncated by the digging activities of the trilobite, suggesting its predation of the worm. The exquisite preservation of ventral axial morphology of the trilobite distinguishes this Rusophycus from simpler bilobate forms attributable to filter-feeding behavior. Congruency in the preservation of worm and trilobite trace supports the conclusion that both were created at the same time, as the trilobite exited the intrastratal burrow. This is the first report of a trilobite hunting burrow from the Ordovician, and the first evidence for predatory behavior for the trilobite genus Isotelus.
Late Paleozoic Problematic sclerites of hercolepadid affinities
Authors: Hoare R. D. , Mapes R. H.
Published: August 2016

Disarticulated spines and sclerites of assumed multiple row problematic organisms are present in several Mississippian and Pennsylvanian stratigraphic units. Marginal spines and dorsal spinose sclerites are present. Marginal sclerites are distinguishable into anterior, posterior, and left- and right-handed lateral forms. The new family Aenigmatectidae and genus Aenigmatectus with two new species, A. hystricosus and A. magnacavus, are recognized. Aenigmatectus sp. from the Mississippian is also described. The family is tentatively assigned to the order Hercolepadida Dzik, 1986.
New Early Devonian styginid trilobites from Victoria, Australia, with revision of some spinose styginids
Authors: Holloway David J.
Published: August 2016

A distinctive new genus (Xyoeax) and two new species (Xyoeax eponcus, Scutellum sudorum) of styginid trilobites are described from the late Early Devonian (Emsian) Murrindal Limestone of eastern Victoria, Australia. Limited material of a third styginid species not belonging to any named genus is also described from the same locality. Xyoeax is considered to be closely related to Ancyropyge Clarke, 1891, and Weberopeltis Maksimova in Moore, 1959, and less closely related to Kolihapeltis Prantl and Přibyl, 1947. Weberopeltis is revised and newly diagnosed. Several species previously assigned to Weberopeltis are transferred to the new genus Exastipyx, which is considered to be related to Cornuscutellum Snajdr, 1960. Ancyropyge, Exastipyx, Weberopeltis, and Xyoeax all have pygidia with long pleural spines derived by reduction of the pleural field between the pleural ribs, whereas Kolihapeltis and Cornuscutellum lack pygidial spines. Pygidial morphology of Xyoeax type has thus arisen independently in separate styginid lineages. The type species of Altaepeltis Maksimova, 1968 is established as Weberopeltis bublitchenkoi Maksimova, 1960, by monotypy.
Terminology of glabellar lobes in trilobite larvae based on homology
Authors: Lee Dong-Chan , Chatterton Brian D. E.
Published: August 2016

Glabellar lobes of holaspid cranidia of trilobites have been numerically designated, LI, L2, etc. (Jaanusson, 1956; Henningsmoen, 1957, figure 1), or lp, 2p, etc. (Harrington, 1959), forward from the occipital ring; most trilobites have four glabellar lobes and an occipital ring. The description of morphological structures with an identical term implies that the structures are homologous in different organisms of a certain group (Inglis, 1966); this is one of the classical definitions of homology (Patterson, 1982). This also seems to be an initial conjecture of homology (“primary homology” of de Pinna, 1991). Likewise, the numerical notation of glabellar lobes should allow us to recognize homology of the lobes among trilobite taxa. Under the above traditional system, the homology is demonstrably recognized in ontogenetic stages with a distinctively differentiated protopygidium (stage 2 in Figure 1); however, this is not the case for earlier intervals occurring before transverse demarcation at the back of the head (stage 1 in Figure 1). This limitation is because the relationships of the occipital ring of the later stages to the posterior axial lobes of the earlier ones are uncertain, and this can be appreciated, when describing a phacopoid protaspis with four axial lobes (stage 1 of Rossaspis pliomeris in Figure 1). We introduce a new term, “Lp”, for the posteriormost axial lobe to remove this limitation, while keeping the traditional system useful. The previous system using letters “L” (after lobus) and “S” (after sulcus), proposed by Jaanusson (1956, p. 37), is preferred over the system using “p”, because “p” of the latter confusingly refers to lobes or furrows (e.g., Harrington and Leanza, 1957, p. 221)
Giganticlavus, a new genus of Pennsylvanian edrioasteroid from North America
Authors: Sumrall Colin D. , Bowsher Arthur L.
Published: August 2016

A new genus and two new species of late Paleozoic edrioasteroids, Giganticlavus bennisoni and G. gelasinus, are described from the Early Pennsylvanian of Oklahoma and New Mexico. Giganticlavus differs from other clavate edrioasteroids by its large size, extreme ambulacral length and ambital overlap, extreme thickness of interambulacral and recumbent zone plates, and the tessellate nature of the recumbent zone plating. The extreme length of ambulacra and thickness of the plating are interpreted as adaptations for increased size and rigidity.
Costacopluma salamancanew species (Decapoda, Retroplumidae) from the Salamanca Formation (Danian) of Patagonia, Argentina
Authors: Feldmann Rodney M. , Rodriguez M. Fernanda , Martinez Gabriela A. , Aguirre-Urreta María
Published: August 2016

The description of a new species of retroplumid crab,Costacopluma salamancafrom the Danian Salamanca Formation, southern Argentina, represents the eighth species referred to that genus and extends the geographic range of the taxon into Patagonia. Cladistic analysis of the genus suggests that three groups of species can be identified based upon their geographic position; Afro-Asian, North American, and South American.
Distribution, history, and taxonomy of theThaisclade (Gastropoda: Muricidae) in the Neogene of tropical America
Authors: Vermeij Geerat J.
Published: August 2016

The earliest known members of theThaisclade of rapanine muricid neogastropods comprise four species from the Cantaure Formation (early Miocene: Burdigalian) of Venezuela; three of these species are new.Neorapana rotundataGibson-Smith et al., 1997, is most closely related to the Recent Pacific MexicanN. tuberculata(Sowerby, 1835), and represents the only known Atlantic occurrence of the genus.Thais breviculanew species is closest toT. callaoensis(Gray, 1828) from the Recent of northern Peru and the Galápagos. A review of the genusThaisindicates that the typical members of this group occur in the South Atlantic, West Africa, and eastern Pacific, but not in the Recent fauna of the southern Caribbean.Stramonita bifidanew species is a large species related to the RecentS. haemastoma floridana(Conrad, 1837), which occurs throughout the Caribbean. A review of American species ofStramonitaindicates that the taxonS. biserialis(de Blainville, 1832) from the Recent fauna of the eastern Pacific, and the taxonS. h. haemastoma(Linnaeus, 1767), may each be composed of more than one species despite the teleplanic dispersal of their larvae.Stramonita semiplicatanew species is closely related to the RecentS. bicarinata(de Blainville, 1832) from the South Atlantic, and represents a lineage that occurred in the Caribbean region until at least the late Miocene. It may have given rise to the eastern Pacific genusAcanthais.The higher diversity and greater antipredatory specialization of eastern Pacific as compared to western Atlantic members of theThaisclade may have resulted from higher post-Miocene rates of speciation and lower extinction rates in the eastern Pacific.
Middle Cambrian fossils from Tizi N'Tichka, the High Atlas, Morocco. Part 2. Hyolitha
Authors: Marek Ladislav , Malinky John M. , Geyer Gerd
Published: August 2016

Shelly fossils from the basal Middle Cambrian, near the peak of Tizi n'Tichka in the central High Atlas, Morocco, include the new hyolithids Oboedalites peregrinus new species, Emarites decorissimus new genus and species, Patholites insolitus new genus and species, Rodentilites cricetus new genus and species, Slapylites afer new species, Tajinella mosei new genus and species, and Tizilites creber new genus and species. New orthothecid hyoliths are Gracilitheca destombesi new species, Contitheca chrosniaki new species, Sysoievia exilis new genus and species and an indeterminate species of Circotheca. The presence of Obeodalites, Slapylites, and Contitheca suggests a strong affinity to other Mediterranean and to Avalonian faunas. Their occurrence in Morocco extends their geographic ranges from Europe, and further reenforces their usefulness as indicators of Middle Cambrian age.
Ontogeny ofStringocephalus gubiensisand the origin ofStringocephalus
Authors: Sun Y. L. , Boucot A. J.
Published: August 2016

A growth series ofStringocephalus gubiensis,described here, reveals that the cardinal process ofStringocephalusoriginated from a bilobate structure, and the growth of its dorsal median septum is highly related to cardinal process development. From this observation we conclude thatKaplexis, structurally and temporally, a suitable ancestor forStringocephalus,withBornhardtinaancestral toKaplex.Subfamilial classification of the family Stringocephalidae is revised based on the presence or absence of median septa and the nature of hinge plates as well as on cardinal process formation. The Kaplexinae and Omoloninae are proposed as new subfamilies, with the Kaplexinae, includingKaplexandErectocephalus,and the Omoloninae, includingOmolonia, Kumbella,andHemistringocephalus.Morphologic study of South China and Western CanadianStringocephalusreveals that late forms of the genus tend to have a higher dorsal septum and more complex cardinal process than the early forms. In view of functional morphology, these trends reflect functional perfection of the cardinal process build-up and the lever system for improving the efficiency of opening and closing the shell.
Bridging the transition between Didelphodonts and Taeniodonts
Authors: Eberle Jaelyn J.
Published: August 2016

The largest documented cimolestid, Alveugena carbonensis new genus and species, is both morphologically and temporally intermediate between small, early cimolestids (such as Procerberus and Cimolestes) and the earliest documented conoryctid taeniodont Onychodectes tisonensis; this represents a transition between the suborders Didelphodonta and Taeniodonta. Diagnosis and description of A. carbonensis is based upon a partial skull and two isolated upper molars recovered from fluvial sandstones at UW locality V-91005, in upper parts of the Ferris Formation, western Hanna Basin, Wyoming. An earliest middle Puercan age for UW locality V-91005 is based upon: presence of taxa that are morphologically intermediate between characteristic early and middle Puercan species; presence of a species of Ectoconus morphologically more primitive than Ectoconus ditrigonus; and co-occurrence of taxa characteristic of Pu1 and Pu2 stratigraphically below and above it. Morphologic trends in evolution of the upper dentition of cimolestids reflect a relative broadening of the crown. A trend toward increasing body size amongst Puercan cimolestids appears to have coincided with a change from a carnivorous (or perhaps insectivorous) to an omnivorous diet, suggested by increased grinding function of the cheek teeth. Cladistic analyses support A. carbonensis as the sister group to O. tisonensis. No known autapomorphies preclude A. carbonensis from having been a plausible ancestor to O. tisonensis.
Morphology, systematics, and evolution of Middle Devonian Ambocoeliidae (Brachiopoda), western New York
Authors: Goldman Daniel , Mitchell Charles E.
Published: August 2016

The internal morphology of ambocoeliid brachiopods from the Middle Devonian Hamilton Group of western New York indicates a need for several taxonomic revisions. “Ambocoelia” praeumbona is transferred to Emanuella. “Ambocoelia” spinosa and “A.” nana represent Crurispina n. gen. Specimens of species belonging to Crurispina have moderately well developed crural plates, and, accordingly, they are assigned to the subfamily Rhynchospiriferinae. Crural plates are small and obscure but clearly present in Ambocoelia umbonata, the type species of Ambocoelia. Thus, the diagnosis of the subfamily Ambocoeliinae is emended to include species with tiny crural plates.

Ambocoeliid specimens from the Levanna Shale Member of the Skaneateles Formation, formerly referred to Echinocoelia, reveal several elaborate features in the pedicle valve, including an apical plate and a hollow tube supported by a median septum. These specimens represent a new genus and species, Mucroclipeus eliei. The homeomorphy found in the shape and size of these ambocoeliids may be the result of paedomorphosis. Additionally, their pattern of occurrence and minute size suggest that they attained their paedomorphic state through progenesis. The taxa Ambocoelia tuberculata n. sp., Crurispina n. gen., and Mucroclipeus eliei n. gen. and sp. are established.
Marginovatia, a mid-Carboniferous genus of linoproductid brachiopods
Authors: Gordon Mackenzie , Henry Thomas W.
Published: August 2016

Marginovatiais proposed as a new genus of small North American linoproductid brachiopods that developed a narrow shelf around the anterior and anterolateral margin of the visceral disc in the brachial valve and a corresponding small flange in the pedicle valve interior. When the valves closed, these structures fit together and helped seal off the visceral cavity. This genus first appeared in the Late Mississippian (late Meramecian), continued through the Early and earliest Middle Pennsylvanian (Morrowan), and may have continued into the early Middle Pennsylvanian (Atokan). In addition to the type species,Productus inflatusvar.minorSnider, seven species are assigned to this genus:Marginovatia aureocollisn. sp.,M. catinulusn. sp.,Linoproductus duodenariusEaston,M. eurekensisn. sp.,M. manardensisn. sp.,Productus(Linoproductus)semicubiculusBell, andL. pumilusSutherland and Harlow. An eighth species, identified asMarginovatiaaff.M. pumila(Sutherland and Harlow), occurs in rocks of probable middle to late Morrowan or Atokan age in southeastern Alaska.
Late Cretaceous gastropods from the Izumi Group of southwest Japan
Authors: Kase Tomoki
Published: August 2016

The basal part of the Upper Cretaceous, mid-Campanian to Maastrichtian Izumi Group of the Izumi Mountains and Awaji Island, Southwest Japan, contains the most diverse gastropod fauna of this age in Japan. This paper discriminates 19 species and describes two new genera:Atira tricarinatan. sp.,Ataphrus(s.s.) sp. A,Ataphrus(s.s.) sp. B,Globularia(s.s.)izumiensisn. sp.,Lysis izumiensisn. sp.,Trichotropis? sp.,Deussenia takinoikensisn. sp.,Volutilithes antiquan. sp.,Pseudoperissitys bicarinataNagao and Otatume,Nekewissp.,Nipponitys inouein. gen. and sp.,Nipponitys acutangularisn. gen. and sp.,Nipponityssp. cf.N. magna(Kalishevitsch),Calorebama cretacean. sp.,Taniella japonican. gen. and sp.,Amuletum(s.s.) sp.,Biplica osakensisn. sp.,Biplica sphaerican. sp., andCylichnasp. The family Ampullospiridae is assigned to the suborder Architaenioglossa from the superfamily Naticacea. The enigmatic genusLysisis tentatively assigned to the Calyptraeidae.Taniella japonican. sp. is the oldest member of the family Olividae, andCalorebama cretacean. sp. is the oldest member of the subfamily Pseudolivinae. Occurrence ofAtira, Ataphrus, Biplica, and five perissityids further supports close communication of the northwestern Pacific Late Cretaceous gastropod faunas with those of the North American Pacific coastal areas.
Cambrian Hyolitha from northeast Canada: reappraisal of the hyolith orders Camerothecida and Diplothecida
Authors: Malinky John M.
Published: August 2016

The hyolith orders Camerothecida Syssoiev and Diplothecida Syssoiev are here incorporated into the order Hyolithida Matthew. Morphologic features used to distinguish Camerothecida and Diplothecida are interpretive reconstructions of features presumed to have been present but not actually preserved on any existing specimens. The few morphologic features retained by those fossils are consistent with assignment to the Hyolithida. Poor preservation of the types ofHyolithes(Camerotheca)gracilisMatthew andDiplotheca hyattianaMatthew, which formed the basis for those two orders, as well as those ofHyolithes(Camerotheca)micmacMatthewinWalcott,Hyolithes acadicaHarttinWalcott, andHyolithes matthewiSinclair, renders generic assignment of these species uncertain.Hyolithes matthewiSinclair is assigned toTulenicornusVal'kov with question, andHyolithes danianumMatthew in Walcott is here transferred toNitoricornusSyssoiev.
Odontopleura (Trilobita, Silurian), and a method of constrained congruency analysis
Authors: Adrain Jonathan M. , Chatterton Brian D. E.
Published: August 2016

Odontopleura (Odontopleura) arctica, a new species of odontopleurine trilobite, is described from the Canadian Arctic. A method of cladistic analysis is detailed. Parsimony analysis should be performed treating all characters as unordered. The universe of directed trees implied by the resulting rootless network(s) can then be examined and a preferred tree selected by a criterion of congruency. Namely, the most parsimonious directed tree that accommodates the most congruent arrangement of character-states should be taken as the preferred cladogram. Since this is essentially a general congruency method operating within the constraints of parsimony, it is termed “constrained congruency.” The method is applied to the genus Odontopleura, resulting in the recognition of two major species groups, the nominate subgenus and Sinespinaspis n. subgen. Odontopleura (Ivanopleura) dufrenoyi Barrande is tentatively included in the genus, but considered too poorly known for cladistic analysis. Species assigned to Odontopleura (Odontopleura) include Odontopleura ovata Emmrich, Odontopleura brevigena Chatterton and Perry, Odontopleura (Odontopleura) arctica n. sp., and Diacanthaspis serotina Apollonov. Species assigned to Sinespinaspis n. subgen. include Taemasaspis llandoveryana Šnajdr, Odontopleura greenwoodi Chatterton and Perry, Odontopleura maccallai Chatterton and Perry, and Odontopleura nehedensis Chatterton and Perry. Odontopleura bombini Chatterton and Perry is tentatively placed in synonymy with Odontopleura nehedensis. The genus had a wide distribution throughout the Early and Middle Silurian, due to preferences for deep-water, distal shelf or shelf-slope transition zone habitats.
A new tabulate coral species from the Pitkin Formation (Chesterian) of north-central Arkansas
Authors: Webb Gregory E.
Published: August 2016

The coral fauna of the Upper Mississippian (Chesterian) Pitkin Formation was described by Easton (1943) and, more recently, by Webb (1987), who defined two coral faunules. The lower faunule occurs throughout the Pitkin outcrop belt from northeastern Oklahoma to north-central Arkansas. The upper faunule has been recognized only in north-central Arkansas where a higher part of the Pitkin is preserved. Equivalent strata have apparently been removed to the west by the pre-Pennsylvanian regional unconformity that differentially truncates Chesterian strata across the Ozark uplift. Thus the upper faunule is less well known than the lower faunule. The purpose of this note is to describe a new tabulate coral from the upper faunule in Searcy County, Arkansas.