Systematics and taxonomy of soft-shelled turtles (Family Trionychidae) from the Judith River Group (mid-Campanian) of North America

1995 ◽  
Vol 32 (5) ◽  
pp. 631-643 ◽  
Author(s):  
James D. Gardner ◽  
Anthony P. Russell ◽  
Donald B. Brinkman
Keyword(s):  
North America ◽  
North American ◽  
Upper Cretaceous ◽  
Cladistic Analysis ◽  
Taxonomic Diversity ◽  
Valid Species ◽  
Western North America ◽  
Fossil Species

Four valid species of trionychine trionychid turtles are recognized from the Upper Cretaceous (mid-Campanian; Judithian) Judith River Group, western North America. Cladistic analysis of extant and Judith River Group trionychines supports referral of three fossil species to Aspideretoides gen. nov. and one fossil species to Apalone, the genus of extant North American trionychines. The taxonomic diversity of Judith River Group trionychids is less than that of younger Maastrichtian and Paleocene assemblages from the Western Interior, largely because of the absence of plastomenine trionychids in the Judith River Group assemblage.

Review of fossil abalone (Gastropoda: Vetigastropoda: Haliotidae) with comparison to Recent species

1999 ◽  
Vol 73 (5) ◽  
pp. 872-885 ◽  
Author(s):  
Daniel L. Geiger ◽  
Lindsey T. Groves
Keyword(s):  
North America ◽  
Upper Cretaceous ◽  
Late Eocene ◽  
Western North America ◽  
Fossil Species ◽  
The Family ◽  
Recent Species ◽  
The Caribbean ◽  
Fossil Records ◽  
Extensive List

Compared to their Recent counterparts, fossil abalone are rare and poorly known. Their taxonomy is problematic, because most of the 35 fossil species have been described from single specimens and shell characteristics of Recent species are extremely plastic. Thus, the use of fossil species in phylogeny is questionable. Abalone first appear in the Upper Cretaceous (Maastrichian) with one species each in California and the Caribbean, are unknown in the Paleocene, and appear again in the late Eocene and Oligocene of New Zealand and Europe. They are regularly found from the late Miocene to the Recent in tropical to temperate regions worldwide. Most records are from intensely studied areas: SW North America, Caribbean, Europe, South Africa, Japan, and Australia. Despite their highest present-day diversity being found in the Indo-Pacific, their scarcity in the fossil record in this region is remarkable. The family may have originated in the central Indo-Pacific, Pacific Rim, or Tethys. An extensive list of all known fossil records including new ones from Europe and western North America is given. Fossil and Recent abalone both apparently lived in the shallow, rocky sublittoral in tropical and temperate climates. No on-shore/off-shore pattern is detected.

scholarly journals Inter- and Intra-Continental Genetic Variation in the Generalist Conifer Wood Saprobic Fungus Phlebiopsis gigantea

Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 751
Author(s):  
Francesco Dovana ◽  
Paolo Gonthier ◽  
Matteo Garbelotto
Keyword(s):  
North America ◽  
Genetic Differentiation ◽  
Dna Sequences ◽  
North American ◽  
Fungal Species ◽  
Coniferous Forests ◽  
Native Forest ◽  
Western North America ◽  
Phlebiopsis Gigantea ◽  
Conifer Wood

Phlebiopsis gigantea (Fr.) Jülich is a well-known generalist conifer wood saprobe and a biocontrol fungus used in several world countries to prevent stump infection by tree pathogenic Heterobasidion fungal species. Previous studies have reported the presence of regional and continental genetic differentiation in host-specific fungi, but the presence of such differentiation for generalist wood saprobes such as P. gigantea has not been often studied or demonstrated. Additionally, little information exists on the distribution of this fungus in western North America. The main purposes of this study were: (I) to assess the presence of P. gigantea in California, (II) to explore the genetic variability of P. gigantea at the intra and inter-continental levels and (III) to analyze the phylogeographic relationships between American and European populations. Seven loci (nrITS, ML5–ML6, ATP6, RPB1, RPB2, GPD and TEF1-α) from 26 isolates of P. gigantea from coniferous forests in diverse geographic distribution and from different hosts were analyzed in this study together with 45 GenBank sequences. One hundred seventy-four new sequences were generated using either universal or specific primers designed in this study. The mitochondrial ML5–ML6 DNA and ATP6 regions were highly conserved and did not show differences between any of the isolates. Conversely, DNA sequences from the ITS, RPB1, RPB2, GPD and TEF1-α loci were variable among samples. Maximum likelihood analysis of GPD and TEF1-α strongly supported the presences of two different subgroups within the species but without congruence or geographic partition, suggesting the presence of retained ancestral polymorphisms. RPB1 and RPB2 sequences separated European isolates from American ones, while the GPD locus separated western North American samples from eastern North American ones. This study reports the presence of P. gigantea in California for the first time using DNA-based confirmation and identifies two older genetically distinct subspecific groups, as well as three genetically differentiated lineages within the species: one from Europe, one from eastern North America and one from California, with the latter presumably including individuals from the rest of western North America. The genetic differentiation identified here among P. gigantea individuals from coniferous forests from different world regions indicates that European isolates of this fungus should not be used in North America (or vice versa), and, likewise, commercially available eastern North American P. gigantea isolates should not be used in western North America forests. The reported lack of host specificity of P. gigantea was documented by the field survey and further reinforces the need to only use local isolates of this biocontrol fungus, given that genetically distinct exotic genotypes of a broad generalist microbe may easily spread and permanently alter the microbial biodiversity of native forest ecosystems.

scholarly journals A New Ankylosaurid Dinosaur from the Upper Cretaceous (Kirtlandian) of New Mexico with Implications for Ankylosaurid Diversity in the Upper Cretaceous of Western North America

PLoS ONE ◽  
2014 ◽  
Vol 9 (9) ◽  
pp. e108804 ◽  
Author(s):  
Victoria M. Arbour ◽  
Michael E. Burns ◽  
Robert M. Sullivan ◽  
Spencer G. Lucas ◽  
Amanda K. Cantrell ◽  
...  
Keyword(s):  
New Mexico ◽  
North America ◽  
Upper Cretaceous ◽  
Western North America

Review of Eohiodon (Teleostei: Osteoglossomorpha) from western North America, with a phylogenetic reassessment of Hiodontidae

1997 ◽  
Vol 71 (6) ◽  
pp. 1109-1124 ◽  
Author(s):  
Li Guo-Qing ◽  
Mark V. H. Wilson ◽  
Lance Grande
Keyword(s):  
North America ◽  
Sister Group ◽  
Sensu Stricto ◽  
Valid Species ◽  
Western North America ◽  
Extant Species ◽  
The Family ◽  
Fossil Records ◽  
Fossil Genus ◽  
Freshwater Teleosts

Review of recently collected material of Eohiodon from North America suggests that there are two valid species, E. rosei (Hussakof) and E. woodroffi Wilson. Eohiodon falcatus Grande is identical to E. woodruffi in known skeletal features and nearly all meristic features and is treated as a junior synonym of the latter. The fossil genus Eohiodon Cavender differs from Hiodon Lesueur, which is known from both fossil and extant species, in numerous meristic and osteological features. The caudal skeleton in Eohiodon is nearly identical to that in Hiodon.The traditionally accepted Notopteroidei, containing Lycopteridae, Hiodontidae, and Notopteridae, is a polypheletic group. The Asian fossil family Lycopteridae is not more closely related to Hiodontidae than it is to other taxa in the Osteoglossomorpha, but is sister to all other Osteoglossomorpha. The Hiodontiformes sensu stricto, including only the family Hiodontidae, is the sister-group of the Osteoglossiformes. This family is not more closely related to notopterids than to other taxa in Osteoglossiformes. The Notopteridae are most closely related to the Mormyroidea; together they and the fossil family Ostariostomidae constitute the sister-group of the Osteoglossoidei.Fossil records of Hiodontiformes sensu stricto and Notopteroidei indicate a widespread pre-Neogene biogeographic range of these freshwater teleosts, suggesting that extinction must have been involved in the Cenozoic evolution of these two osteoglossomorph sublineages.

scholarly journals Bombus (Pyrobombus) johanseni Sladen, 1919, a valid North American bumble bee species, with a new synonymy and comparisons to other “red-banded” bumble bee species in North America (Hymenoptera, Apidae, Bombini)

ZooKeys ◽  
2020 ◽  
Vol 984 ◽  
pp. 59-81
Author(s):  
Cory S. Sheffield ◽  
Ryan Oram ◽  
Jennifer M. Heron
Keyword(s):  
North America ◽  
North American ◽  
Dna Barcode ◽  
Molecular Data ◽  
The Arctic ◽  
Valid Species ◽  
Bumble Bee ◽  
Widespread Species ◽  
Old World ◽  
Northern Canada

The bumble bee (Hymenoptera, Apidae, Bombini, Bombus Latreille) fauna of the Nearctic and Palearctic regions are considered well known, with a few species occurring in both regions (i.e., with a Holarctic distribution), but much of the Arctic, especially in North America, remains undersampled or unsurveyed. Several bumble bee taxa have been described from northern North America, these considered either valid species or placed into synonymy with other taxa. However, some of these synonymies were made under the assumption of variable hair colour only, without detailed examination of other morphological characters (e.g., male genitalia, hidden sterna), and without the aid of molecular data. Recently, Bombus interacti Martinet, Brasero & Rasmont, 2019 was described from Alaska where it is considered endemic; based on both morphological and molecular data, it was considered a taxon distinct from B. lapponicus (Fabricius, 1793). Bombus interacti was also considered distinct from B. gelidus Cresson, 1878, a taxon from Alaska surmised to be a melanistic form of B. lapponicus sylvicola Kirby, 1837, the North American subspecies (Martinet et al. 2019). Unfortunately, Martinet et al. (2019) did not have DNA barcode sequences (COI) for females of B. interacti, but molecular data for a melanistic female specimen matching the DNA barcode sequence of the holotype of B. interacti have been available in the Barcodes of Life Data System (BOLD) since 2011. Since then, additional specimens have been obtained from across northern North America. Also unfortunate was that B. sylvicola var. johanseni Sladen, 1919, another melanistic taxon described from far northern Canada, was not considered. Bombus johanseni is here recognized as a distinct taxon from B. lapponicus sylvicola Kirby, 1837 (sensuMartinet et al. 2019) in the Nearctic region, showing the closest affinity to B. glacialis Friese, 1902 of the Old World. As the holotype male of B. interacti is genetically identical to material identified here as B. johanseni, it is placed into synonymy. Thus, we consider B. johanseni a widespread species occurring across arctic and subarctic North America in which most females are dark, with rarer pale forms (i.e., “interacti”) occurring in and seemingly restricted to Alaska. In addition to B. johanseni showing molecular affinities to B. glacialis of the Old World, both taxa also inhabit similar habitats in the arctic areas of both Nearctic and Palearctic, respectively. It is also likely that many of the specimens identified as B. lapponicus sylvicola from far northern Canada and Alaska might actually be B. johanseni, so that should be considered for future studies of taxonomy, distribution, and conservation assessment of North American bumble bees.

scholarly journals Influence of ENSO on North American subseasonal surface air temperature variability

2021 ◽  
Vol 2 (2) ◽  
pp. 395-412
Author(s):  
Patrick Martineau ◽  
Hisashi Nakamura ◽  
Yu Kosaka
Keyword(s):  
North America ◽  
Air Temperature ◽  
North American ◽  
Surface Air Temperature ◽  
Tropical Pacific ◽  
La Niña ◽  
Western North America ◽  
The North ◽  
Subseasonal Variability ◽  
La Nina

Abstract. The wintertime influence of tropical Pacific sea surface temperature (SST) variability on subseasonal variability is revisited by identifying the dominant mode of covariability between 10–60 d band-pass-filtered surface air temperature (SAT) variability over the North American continent and winter-mean SST over the tropical Pacific. We find that the El Niño–Southern Oscillation (ENSO) explains a dominant fraction of the year-to-year changes in subseasonal SAT variability that are covarying with SST and thus likely more predictable. In agreement with previous studies, we find a tendency for La Niña conditions to enhance the subseasonal SAT variability over western North America. This modulation of subseasonal variability is achieved through interactions between subseasonal eddies and La Niña-related changes in the winter-mean circulation. Specifically, eastward-propagating quasi-stationary eddies over the North Pacific are more efficient in extracting energy from the mean flow through the baroclinic conversion during La Niña. Structural changes of these eddies are crucial to enhance the efficiency of the energy conversion via amplified downgradient heat fluxes that energize subseasonal eddy thermal anomalies. The enhanced likelihood of cold extremes over western North America is associated with both an increased subseasonal SAT variability and the cold winter-mean response to La Niña.

A New Gunnel, Pholis clemensi, from the Coast of Western North America

1964 ◽  
Vol 21 (5) ◽  
pp. 933-939 ◽  
Author(s):  
Richard H. Rosenblatt
Keyword(s):  
British Columbia ◽  
New Species ◽  
North America ◽  
North American ◽  
North American Species ◽  
Western North America ◽  
The North ◽  
The Family ◽  
Juan De Fuca ◽  
A New Species

A new species, Pholis clemensi, referred to the family Pholidae, is named and described from 12 specimens taken in southern British Columbia waters and the Strait of Juan de Fuca. Pholis clemensi is compared with other members of the genus, and a key is given to the North American species.

The Impact of Sea Surface Temperature Biases on North American Precipitation in a High-Resolution Climate Model

2020 ◽  
Vol 33 (6) ◽  
pp. 2427-2447 ◽  
Author(s):  
Nathaniel C. Johnson ◽  
Lakshmi Krishnamurthy ◽  
Andrew T. Wittenberg ◽  
Baoqiang Xiang ◽  
Gabriel A. Vecchi ◽  
...  
Keyword(s):  
North America ◽  
Surface Temperature ◽  
North Atlantic ◽  
North American ◽  
North Pacific ◽  
Climate Model ◽  
Sea Surface ◽  
Tropical Atlantic ◽  
Western North America ◽  
The North

AbstractPositive precipitation biases over western North America have remained a pervasive problem in the current generation of coupled global climate models. These biases are substantially reduced, however, in a version of the Geophysical Fluid Dynamics Laboratory Forecast-Oriented Low Ocean Resolution (FLOR) coupled climate model with systematic sea surface temperature (SST) biases artificially corrected through flux adjustment. This study examines how the SST biases in the Atlantic and Pacific Oceans contribute to the North American precipitation biases. Experiments with the FLOR model in which SST biases are removed in the Atlantic and Pacific are carried out to determine the contribution of SST errors in each basin to precipitation statistics over North America. Tropical and North Pacific SST biases have a strong impact on northern North American precipitation, while tropical Atlantic SST biases have a dominant impact on precipitation biases in southern North America, including the western United States. Most notably, negative SST biases in the tropical Atlantic in boreal winter induce an anomalously strong Aleutian low and a southward bias in the North Pacific storm track. In boreal summer, the negative SST biases induce a strengthened North Atlantic subtropical high and Great Plains low-level jet. Each of these impacts contributes to positive annual mean precipitation biases over western North America. Both North Pacific and North Atlantic SST biases induce SST biases in remote basins through dynamical pathways, so a complete attribution of the effects of SST biases on precipitation must account for both the local and remote impacts.

An Early Cretaceous (Berriasian) fossil-bearing locality from the Rocky Mountains of Alberta, yielding the oldest dinosaur skeletal remains from western Canada

2020 ◽  
Vol 57 (4) ◽  
pp. 542-552 ◽  
Author(s):  
Ramon S. Nagesan ◽  
James A. Campbell ◽  
Jason D. Pardo ◽  
Kendra I. Lennie ◽  
Matthew J. Vavrek ◽  
...  
Keyword(s):  
North America ◽  
Early Cretaceous ◽  
Depositional Environment ◽  
Upper Cretaceous ◽  
Upper Jurassic ◽  
High Energy ◽  
Western Canada ◽  
Western North America ◽  
Terrestrial Vertebrate ◽  
Overlying Strata

Western North America preserves iconic dinosaur faunas from the Upper Jurassic and Upper Cretaceous, but this record is interrupted by an approximately 20 Myr gap with essentially no terrestrial vertebrate fossil localities. This poorly sampled interval is nonetheless important because it is thought to include a possible mass extinction, the origin of orogenic controls on dinosaur spatial distribution, and the origin of important Upper Cretaceous dinosaur taxa. Therefore, dinosaur-bearing rocks from this interval are of particular interest to vertebrate palaeontologists. In this study, we report on one such locality from Highwood Pass, Alberta. This locality has yielded a multitaxic assemblage, with the most diagnostic material identified so far including ankylosaurian osteoderms and a turtle plastron element. The fossil horizon lies within the upper part of the Pocaterra Creek Member of the Cadomin Formation (Blairmore Group). The fossils are assigned as Berriasian (earliest Cretaceous) in age, based on previous palynomorph analyses of the Pocaterra Creek Member and underlying and overlying strata. The fossils lie within numerous cross-bedded sandstone beds separated by pebble lenses. These sediments are indicative of a relatively high-energy depositional environment, and the distribution of these fossils over multiple beds indicates that they accumulated over multiple events, possibly flash floods. The fossils exhibit a range of surface weathering, having intact to heavily weathered cortices. The presence of definitive dinosaur material from near the Jurassic–Cretaceous boundary of Alberta establishes the oldest record of dinosaur body fossils in western Canada and provides a unique opportunity to study the Early Cretaceous dinosaur faunas of western North America.

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