Megamouth Shark Morphometrics
Krak and Shimada use geometric morphometrics to reconstruct extinct megamouth shark tooth rows
Allonia from the middle Cambrian Wheeler Formation of Utah
Foster, Howells and Sroka report new details of early sponge-like animals from a spectacularly-preserved specimen from the Cambrian of western Utah.
Death Valley Devonian Acanthodians
A new stem chondrichthyan fauna from the Lost Burro Formation of California by Carole J. Burrow and David K. Elliot.
Toxochelys latiremis Cope, 1873
First report of this turtle from the Cretaceous of Alabama, USA by Andrew Gentry and Jun Ebersole.
Calliovarica oregonensis Hickman
A new species of chilodontid gastropod from the Eocene of Oregon, USA by Carole S. Hickman.
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.
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!
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.
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.
New report of the fossil otolith species, Equetulus silveraldensis n. comb., from the Oligocene of the Gulf Coastal Plain, USA!
Stringer et al. describe the first record of the teleostean fish otolith, Equetulus silveraldensis n. comb., from the Oligocene of Alabama, USA, and its enigmatic geographic distribution.
New dinosauromorph body fossils from the Petrified Forest National Park, Arizona, USA!
Adam Marsh and William Parker describe new dinosauromorph specimens from the Chinle Formation Petrified Forest National Park and provide a global biostratigraphic review of Triassic dinosauromorphs.
Checklist of Paleogene-Neogene marine Mollusca from California!
Groves and Squires present an annotated catalog of Paleogene-Neogene Mollusca from California since Keen and Bentson's 1944 checklist.
New mid-Miocene equids from the Cajon Valley Formation, CA!
Stoneburg et al. describe new fossil horse remains from the mid-Miocene of San Bernardino County, CA.
New fossil fishes from South Carolina, USA!
Cicimurri et al. report on a diverse fauna of Oligocene fishes from the Ashley Formation of South Carolina, with description of a new catshark species, Scyliorhinus weemsi.
Changes in southern California oyster paleocommunity structure over the last 3.6 million years!
Bonuso et al. use digitized data from the EPICC TCN and other sources to reconstruct Late Cenozoic oyster communities in southern California, USA.
The earliest Ancistrolepis, from the early Eocene of Simi Valley, California, USA
Squires updates our knowledge of the oldest species of this extant buccinid gastropod genus
The first Cretaceous fish otolith assemblage from the Arkadelphia Formation of Arkansas, USA!
Stringer and Sloan describe the first otolith assemblage from the Late Cretaceous of Arkansas and its implications for our understanding of the Western Interior Seaway.
Pteriomorph bivalves from the Eocene-Oligocene Keasey Formation in Oregon, USA!
Hickman describes the pteriomorph bivalves from the Eocene-early Oligocene Keasey Formation in Oregon, recognizing a new peri-seep biotope association.
Volume 29, Issue 3, 2010
Articles
Estimating polyploidy levels in fossil Salix: A critical review of cell size proxy methods
Studies have used cell size as a proxy to estimate polyploidy levels, the number of chromosome sets in somatic cells, in modern and fossil plant species. This paper critically evaluates these methods by reviewing cell size- and polyploidy-related literature, and provides new cell size data from herbarium material and fossil remains of willow genus Salix. The 40 extant taxa used in the study include most of the polyploidy levels encountered in Salix (2n = 38, 76, 114, 152, 190). Diploid and tetraploid species were morphologically similar to the fossil specimens. Specimens from alpine and arctic regions, forms rarely found in the fossil record, were included to extend the range of polyploidy levels. Measurements taken for this study were on the petiole epidermal cells of fossil and herbarium specimens and the stomatal guard cell complexes of herbarium material. A literature review reveals cell size may not relate only to DNA content, but to a plant’s age, nutritional state and the seasonal timing of organ development. Cell size measurements show that cultivated plants grown at elevations more than 800 m below their original place of growth have a significant increase in cell size. Leaf length-to-width ratio, infrageneric classification, and adaptation to dry or humid environments also correlate with cell size. Cell size proxies for estimating polyploidy levels in fossil willows provide only accurate results if morphologically similar modern plant material from natural habitats is used as a reference for comparison. Leaves should be similar in overall shape, base and apex shape, blade length and width, length-to-width ratio, petiole length, petiole-to-blade length ratio, venation pattern, and margin dentition.
A Machairodont felid (Mammalia; Carnivora; Felidae) from the latest Hemphillian (Late Miocene/Early Pliocene) Bidahochi Formation, northeastern Arizona
A lower jaw from the White Cone local fauna of the latest Hemphillian Bidahochi Formation in northern Arizona is the first description of a felid from this fauna and the first positively identified occurrence of the smilodontine machairodont Paramachairodus in North America. This lower jaw has characters identical to those seen in a similar sized machairodont felid from the Bone Valley Formation of Florida, suggesting that the same taxon is present in Florida. The diversity of the Hemphillian machairodonts and the taxonomic status of Megantereon hesperus is reviewed. The characteristics of the ramus corpus and dentition places Paramachairodus firmly within the Smilodontini and adds further support that the more derived smilodontine machairodonts, Megantereon and Smilodon, had their origins in North America.