Faunal change in Cretaceous endemic bivalves of the northeast Pacific!
Richard Squires reports on the faunal change in Cretaceous shallow-marine endemic bivalve genera/subgenera of the northeast Pacific region.
First leatherback sea turtle (family Dermochelyidae) from the Mio-Pliocene Purisima Formation of California!
Bailey Fallon and Bobby Boessenecker describe the first leatherback sea turtle, cf. Psephophorus, from the lower Pliocene Purisima Formation of California, USA.
The Miocene Mascall vertebrate fauna revisited!
An excellent update of the vertebrate fauna and chronostratigraphy of the Miocene type Mascall Formation, John Day Basin, Oregon, USA by Kaitlin Clare Maguire, Joshua Samuels, and Mark Schmitz.
Toxochelys latiremis Cope, 1873
First report of this turtle from the Cretaceous of Alabama, USA by Andrew Gentry and Jun Ebersole.
Program and abstracts for the 52nd annual meeting of the Western Association of Vertebrate Paleontologists held at Dixie State University in St. George, Utah, USA.
Calliovarica oregonensis Hickman
A new species of chilodontid gastropod from the Eocene of Oregon, USA by Carole S. Hickman.
Late Triassic vertebrates from the Dockum Group of Texas!
New apomorphy-based identifications of vertebrates from the Late Triassic Dockum Group of Texas by Lessner et al.
An EPICC contribution!
Annotated list of the Cenozoic marine formations of the Pacific Northwest by Liz Nesbitt.
Use of machine learning to classify extant apes!
Monson et al. apply machine learning using dental morphology to classify extant apes and shed light on the chimpanzee-human last common ancestor.
New subadult skull specimen of Euclastes wielandi Hay, 1908 from the Cretaceous of New Jersey, USA!
New study of a subadult skull by P. Ullmann, Z. Boles and M. Knell provides insights into the cranial morphology and intraspecific variation in the Cretaceous pan-cheloniid turtle Euclastes wielandi.
Cimolestids (Mammalia) from the Paleocene of Montana!
New report on Puercolestes and Betonnia, two cimolestids from the early Paleocene (Puercan) of northeastern Montana, U.S.A. by William A. Clemens.
Eocene cassid gastropods from North America!
A reassessment by Richard Squires of Eocene warm-water cassid gastropods (Family Cassidae) from North America and implications for their paleogeographic distribution and faunal turnover following the Paleocene-Eocene Thermal Maximum.
Late Eocene elasmobranchs from Aiken County, South Carolina, USA!
Cicimurri and Knight describe new material of sharks and rays (elasmobrachs) from the Dry Branch Formation of Aiken County, South Carolina USA.
NAPC 2019 Field trip guide to the Ediacaran-Cambrian transition in the southwestern USA!
Field trip guide to the Ediacaran-Cambrian transition led by E. Smith, L. Tarhan and L. Nelson for the 2019 North American Paleontological Convention (NAPC).
Late Cretaceous endemic shallow-marine gastropods of the northeast Pacific!
Biodiversity and faunal changes in Late Cretaceous northeast Pacific gastropods by Richard L. Squires.
NAPC 2019 field trip guide to the geology and paleontology of Miocene formations in southern California!
Katharine Loughney and Tara Smiley's NAPC 2019 field trip guide to the geology and paleontology of the Miocene Barstow, Crowder, and Cajon Valley formations of southern California.
Program and Abstracts for the 11th North American Paleontological Conference!
Program and Abstracts for the 11th North American Paleontological Conference (NAPC) hosted by University of California, Riverside June 23-27, 2019.
Nestling-sized hadrosaurine crania from the Late Cretaceous of Montana!
Wosik et al. describe new cranial remains of hadrosaurine nestlings from the Late Cretaceous Hell Creek Formation, Montana, USA, with analysis of cranial ontogeny in Edmontosaurus annectens.
Miocene macropaleontology of the Caldecott Tunnel fourth bore excavation, Berkeley Hills, CA, USA!
Powell et al. describe Miocene marine macrofossils recovered from the fourth bore excavation of the Caldecott Tunnel in the Berkeley Hills, Oakland, CA, USA.
New protocol for differentiating leporids from the late Quaternary of southern California, USA!
Fox et al. propose new protocol using dental morphology for identifying late Quaternary leporids from southern California with remarks on lagomorphs from Rancho La Brea's Project 23!
A new drepanosauromorph from the Chinle Formation of Petrified Forest National Park, Arizona, USA!
Gonçalves and Sidor describe the new Triassicdrepanosauromorph genus and species,Ancistronychus paradoxus, from the Chinle Formation of the Petrified Forest National Park, Arizona, USA!
New limpets from the Miocene of southern California, USA!
Charles Powell and Daniel Geiger describe and name two new limpet species, Scelidotoma aldersoni n. sp. and Fissurella? stantoni n. sp. from the Miocene of southern California, USA.
Epiplastral shape and geographic variation of Echmatemys from the Eocene of Utah!
Heather F. Smith et al. analyze epiplastral shape and geographic variation in thegeoemydid turtle, Echmatemys,from the Eocene Uinta Basin , Utah, USA.
The new species Lyropecten terrysmithae from the Miocene of central California!
Powell et al. describe and name a new pectinid, Lyropecten terrysmithae , from the Miocene of California in honor of Dr. Judy Terry Smith for her work on California and Mexican invertebrate paleontology.
Volume 30, Issue 1, 2011
Herpetocetine (Cetacea: Mysticeti) dentaries from the Upper Miocene Santa Margarita Sandstone of Central California
Two fossil baleen whale (Mysticeti) dentaries from the Upper Miocene (10–12 Ma) Santa Margarita Sandstone of Central California preserve several distinct features similar to the enigmatic herpetocetine whale Herpetocetus. These features include an elongate coronoid process, a mandibular condyle with a planar articular surface, and a posteriorly extended angular process. The dentary is unknown for several Herpetocetinae (and the more inclusive clade Cetotheriidae), including the coeval Nannocetus eremus. This occurrence would extend the known record of Herpetocetus by 6 Ma. Given the currently poor knowledge of Pacific Cetotheriidae during the Miocene, these specimens are identified to the subfamily Herpetocetinae, despite the similarity of these specimens to Herpetocetus. As the morphology of the supposedly distinctive lectotype dentary of Herpetocetus scaldiensis (the type species of Herpetocetus) may not be unique to Herpetocetus, this study suggests that the mandibular morphology of fossil mysticetes may be more homoplastic (or conservative) than previously assumed. Mysticete taxonomy should employ autapomorphic characters beyond the morphology of the dentary alone.
The carpometacarpus of the Pliocene turkey Meleagris leopoldi (Galliformes: Phasianidae) and the problem of morphological variability in turkeys
I describe the first known carpometacarpus attributable to the extinct late Pliocene (Blancan) turkey Meleagris leopoldi that was apparently collected with the type material at the type locality in Cita Canyon, Texas. Although known to previous workers, this specimen has never been discussed or described. The size and morphology of the carpometacarpus indicates that M. leopoldi may be distinct from the extant M. gallopavo and is similar to Meleagris progenes and Inglis 1A (Florida) material. However, this fossil does not clarify the relationship to and possible synonymy of M. leopoldi and M. anza, but it adds support to the idea that M. progenes is a junior synonym of M. leopoldi. The extreme morphological variation among fossil turkey specimens and recognized species obscures the phylogenetic relationships among Meleagris taxa. The presence of certain variable characters in geologically older Meleagris taxa may provide a clue to assess character polarity. Given these data, it appears that Meleagris leopoldi was a widely distributed late Pliocene species that was replaced in its geographic range by M. gallopavo during the Pleistocene.
The skull of Postosuchus kirkpatricki (Archosauria: Paracrocodyliformes) from the Upper Triassic of the United States
The skull of Postosuchus kirkpatricki Chatterjee 1985 is known from the holotype and paratype specimens along with disassociated skull elements from several Triassic localities in the southwestern and eastern United States. Recent preparation of the holotype skull allows for more careful examination of the cranial elements and comparison with related taxa. This description indicates that Postosuchus shares several previously unrecognized synapomorphies with crocodylomorphs, including fossae and foramina in the dermatocranium that are not present in other basal pseudosuchians. The sutural arrangements of the skull of Postosuchus presented in this paper differ considerably from previous descriptions, due in part to the reassignment of what was previously considered the prefrontal to the palpebral bone. Also, further preparation of skull elements revealed morphologies that differ from previous descriptions. This new description also indicates a close relationship with Polonosuchus silesiacus Sulej 2005. The only autapomorphic characters of the skull are a distinct, rounded lateral ridge on the maxilla and a foramen present in a large fossa on the anteromedial surface of the maxilla.