Craniodental morphology and diet ofLeptarctus oregonensis(Mammalia, Carnivora, Mustelidae) from the Mascall Formation (Miocene) of central Oregon

2017 ◽  
Vol 92 (2) ◽  
pp. 289-304 ◽  
Author(s):  
Jonathan J. Calede ◽  
Winifred A. Kehl ◽  
Edward B. Davis
Keyword(s):  
Sexual Dimorphism ◽  
North America ◽  
Intraspecific Variation ◽  
Geographic Distribution ◽  
North American ◽  
Distinct Species ◽  
Land Mammal ◽  
Distinct Morphology

AbstractThe Leptarctinae are an enigmatic subfamily of mustelids present in North America and Eurasia during the Miocene (Arikareean to Hemphillian North American Land Mammal Ages). Their diet and ecology have been particularly controversial. Some workers have suggested they were similar to koalas, whereas others suggested they were crushing omnivores analogous to raccoons.Leptarctus oregonensisStock, 1930, a poorly known leptarctine from the early Barstovian, is represented by fragmented cranial elements and isolated teeth from the Mascall Formation of Oregon, and some fairly complete but undescribed material from the Olcott Formation of western Nebraska. Herein, we describe the first well-preserved skull ofL.oregonensisfrom the type formation. Based on this new specimen, we confirm thatL.oregonensisis a distinct species fromL.primusLeidy, 1856 andL.ancipidensWhite, 1941 that is characterized by a distinct morphology of its tympanic projections and first upper molars. We are also able to describe intraspecific variation withinL.oregonensiscoinciding with the geographic distribution of the specimens (Oregon and Nebraska). The most variable characters are concentrated in the morphology of the frontals and the upper fourth premolar. Additional specimens will be needed to settle the debate over sexual dimorphism in this species, but this new specimen suggests thatLeptarctus oregonensis, despite being one of the smallest members of the Leptarctinae, was an animal-dominated omnivore with considerable crushing ability.

scholarly journals Intraspecific Variation in a Scorpionfly Newly Recorded from Texas and the State of Taxonomy of North American Panorpidae (Mecoptera)

2010 ◽  
Vol 2010 ◽  
pp. 1-5
Author(s):  
Joshua R. Jones
Keyword(s):  
North America ◽  
Intraspecific Variation ◽  
North American ◽  
Original Description ◽  
The State ◽  
Taxonomic Review ◽  
Intraspecific Variations ◽  
First Time

Panorpa vernalisByers is recorded for the first time from Texas, and represents only the second species ofPanorpadocumented from the state. Intraspecific variations between the Texas specimens and Byers' original description are discussed. A synopsis of the principal modern keys for identification of North AmericanPanorpais provided, and an argument for a modern taxonomic review of the Panorpidae of North America is presented.

Ecogeography and the Great American Interchange

Paleobiology ◽  
1991 ◽  
Vol 17 (3) ◽  
pp. 266-280 ◽  
Author(s):  
S. David Webb
Keyword(s):  
North America ◽  
South America ◽  
North American ◽  
Mammalian Fauna ◽  
The South ◽  
Land Bridge ◽  
Southern Mexico ◽  
The North ◽  
Land Mammal ◽  
The Impact

When the isthmian land bridge triggered the Great American Interchange, a large majority of land-mammal families crossed reciprocally between North and South America at about 2.5 Ma (i.e., Late Pliocene). Initially land-mammal dynamics proceeded as predicted by equilibrium theory, with roughly equal reciprocal mingling on both continents. Also as predicted, the impact of the interchange faded in North America after about 1 m.y. In South America, contrary to such predictions, the interchange became decidedly unbalanced: during the Pleistocene, groups of North American origin continued to diversify at exponential rates. Whereas only about 10% of North American genera are derived from southern immigrants, more than half of the modern mammalian fauna of South America, measured at the generic level, stems from northern immigrants. In addition, extinctions more severely decimated interchange taxa in North America, where six families were lost, than in South America, where only two immigrant families became extinct.This paper presents a two-phase ecogeographic model to explain the asymmetrical results of the land-mammal interchange. During the humid interglacial phase, the tropics were dominated by rain forests, and the principal biotic movement was from Amazonia to Central America and southern Mexico. During the more arid glacial phase, savanna habitats extended broadly right through tropical latitudes. Because the source area in the temperate north was six times as large as that in the south, immigrants from the north outnumbered those from the south. One prediction of this hypothesis is that immigrants from the north generally should reach higher latitudes in South America than the opposing contingent of land-mammal taxa in North America. Another prediction is that successful interchange families from the north should experience much of their phylogenetic diversification in low latitudes of North America before the interchange. Insofar as these predictions can be tested, they appear to be upheld.

Taxonomic studies on the genus Atrichum in North America

1969 ◽  
Vol 47 (3) ◽  
pp. 353-368 ◽  
Author(s):  
Robert R. Ireland
Keyword(s):  
United States ◽  
North America ◽  
North American ◽  
Distinct Species ◽  
The United States ◽  
Morphological Characters ◽  
Taxonomic Study ◽  
Chromosome Counts ◽  
The Status ◽  
Taxonomic Studies

A taxonomic study was made of several North American taxa in the genus Atrichum. The primary emphasis was on the Canadian taxa and a key to the six species (A. altecristatum, A. angustatum, A. crispum, A. oerstedianum, A. selwynii, A. undulatum) and one variety (A. undulatum var. gracilisetum) of the country is presented. Atrichum oerstedianum, which has been confused with A. undulatum, is added to the moss flora of the United States and Canada. The distribution of A. crispum is clarified and a detailed study of the species revealed new morphological characters that are useful to distinguish it. A variety of A. undulatum, the var. altecristatum, is raised to the rank of a species and morphological and distributional data are given to support the status of A. selwynii as a distinct species. The first chromosome counts are reported for A. selwynii (n = 7) and A. altecristatum (n = 14). Detailed descriptions are provided for A. altecristatum, A. crispum, A. oerstedianum, and A. selwynii.

scholarly journals Molecular systematics of some North American species of Diplostomum (Digenea) based on rDNA-sequence data and comparisons with European congeners

2002 ◽  
Vol 80 (12) ◽  
pp. 2207-2217 ◽  
Author(s):  
Daniel E Galazzo ◽  
Selvadurai Dayanandan ◽  
David J Marcogliese ◽  
J Daniel McLaughlin
Keyword(s):  
North America ◽  
North American ◽  
Sequence Data ◽  
Intestinal Parasites ◽  
Distinct Species ◽  
North American Species ◽  
Similar Species ◽  
The North ◽  
Diplostomum Spathaceum ◽  
Rdna Sequence Data

The systematics of Diplostomum species, common intestinal parasites of piscivorous birds, has long been problematic, owing to phenotypic plasticity and the paucity of morphological features that are often subject to age- and host-induced variation. We sequenced the ITS1–5.8S–ITS2 regions of the rDNA from adult Diplostomum huronense, Diplostomum indistinctum, and Diplostomum baeri obtained from experimentally infected ring-bill gulls (Larus delawarensis) and compared them with partial ITS1 sequences from several species of Diplostomum in GenBank. The three North American species were distinguishable on the basis of ITS sequences. Sequences from D. huronense differed from those of D. indistinctum at 12 sites in ITS1 and 4 sites in ITS2, supporting morphological and morphometric data that indicate the two are distinct species. Sequences of D. huronense and D. indistinctum differed from those of D. baeri at 27 and 24 sites, respectively, in ITS1 and 15 and 12 sites, respectively, in ITS2. Phylogenetic analysis of partial ITS1 sequences revealed that the North American and European species of Diplostomum formed separate groups, with the former being basal to the latter. The results indicated that D. huronense and D. indistinctum from North America are distinct from Diplostomum spathaceum and other similar species from Europe. Furthermore, sequences from specimens identified as D. baeri from North America differed from those of D. baeri from Europe by 3.8% in ITS1 (23 sites). While morphologically similar, the two are not conspecific. Sequences of the North American species have been deposited in GenBank (AY 123042–123044).

Polymorphism in Languria taedata LeConte, its occurrence in coastal Louisiana Spartina marshes, and clarification of some Motschulsky languriine types (Coleoptera: Erotylidae: Languriinae)

Zootaxa ◽  
2012 ◽  
Vol 3237 (1) ◽  
pp. 24 ◽  
Author(s):  
MATTHEW L. GIMMEL ◽  
CHRISTOPHER E. CARLTON ◽  
WILLIAM H. WHITE
Keyword(s):  
North America ◽  
Geographical Distribution ◽  
Spartina Alterniflora ◽  
Geographic Distribution ◽  
North American ◽  
Gulf Coast ◽  
Coastal Species ◽  
Coastal Louisiana ◽  
New Synonymy ◽  
Range Of Variation

We clarify the diagnosis and geographic distribution of the widespread, variable eastern coastal species Languria taedataLeConte, 1854, in North America. After examining types and the range of variation and geographical distribution of thespecies, we propose synonymy of L. erythrocephalus Blatchley, 1924, with L. taedata, new synonymy. We report the dis-covery of an all-piceous form (“Form C”), the first of the genus, found primarily along the western Gulf Coast of the Unit-ed States. The recognition of this form requires a modification to the most recent key to North American genera ofLanguriinae. The larvae of L. taedata feed within the stems of Spartina alterniflora Loisel (Poaceae). We provide addi-tional notes on the occurrence of L. taedata in coastal marshes in Louisiana. The types of L. apicalis Motschulsky, L. ni-griceps Motschulsky, L. obscura Motschulsky, and L. rufiventris are reexamined. A revised synonymic checklist is provided for North American Languriini.

Circumscription of species of Hodophilus (Clavariaceae, Agaricales) in North America with naphthalene odours

Botany ◽  
2016 ◽  
Vol 94 (10) ◽  
pp. 941-956 ◽  
Author(s):  
Slavomír Adamčík ◽  
Brian P. Looney ◽  
Joshua M. Birkebak ◽  
Soňa Jančovičová ◽  
Katarína Adamčíková ◽  
...  
Keyword(s):  
North America ◽  
North American ◽  
Phylogenetic Analyses ◽  
Distinct Species ◽  
Morphological Type ◽  
Morphological Data ◽  
Western North America ◽  
Phylogenetic Species ◽  
New Approach ◽  
Previously Treated

Five North American Hodophilus species with naphthalene-like odours are now recognized based on sequence and (or) morphological data and molecular annotation of type collections. Two well-supported eastern North American species do not match any of the studied types and are described here as new: Hodophilus hesleri and Hodophilus smithii. The previously described Hodophilus paupertinus is found to represent an autonomous species and appears restricted to western North America. Hodophilus subfuscescens is found to be an independent lineage in eastern North America. A morphological type study of Hodophilus peckianus shows that it is a distinct species and not represented among recent collections. Multilocus phylogenetic analyses of European and North American material of species with naphthalene odours reveal no species with transatlantic distributions. Overall, Hodophilus comprises two superclades (the Hodophilus foetens superclade and the Hodophilus micaceus superclade) and 16 terminal clades that correspond to phylogenetic species. This study introduces a new approach for morphological delimitation of agaricoid Clavariaceae combining shape and dimensions of particular elements in the pileipellis and caulocystidia. All previously described taxa included in this study, which were previously treated in the genera Hygrophorus, Camarophyllopsis, or Hygrotrama, are formally transferred to Hodophilus.

scholarly journals Reassessing the taxonomic diversity of Plagiothecium section Orthophyllum in the North American bryoflora

Brittonia ◽  
2020 ◽  
Vol 72 (4) ◽  
pp. 337-350 ◽  
Author(s):  
Grzegorz J. Wolski
Keyword(s):  
Twentieth Century ◽  
North America ◽  
Northern Hemisphere ◽  
North Africa ◽  
North American ◽  
Taxonomic Diversity ◽  
Distinct Species ◽  
Morphological Features ◽  
Ecological Preferences ◽  
The North

AbstractAt the beginning of the twentieth century, Plagiothecium nemorale s.l. and P. succulentum, both belonging to P. sect. Orthophyllum, were considered to be distributed across almost the entire Northern Hemisphere. However, in the mid-twentieth century these taxa were recircumscribed resulting in their exclusion from the North American bryoflora and restricting their distributions to Asia and Europe, and in the case of Plagiothecium nemorale s.l., also North Africa. More recently, it was found that P. nemorale s.l. is a taxonomic complex comprising three distinct species: P. nemorale s.s., P. longisetum, and P. angusticellum. I revised the North American material of P. section Orthophyllum deposited in three herbaria (NY, FH, F) and found that five examined taxa of the section are present in the North America. Two of the species P. angusticellum and P. longisetum, have not been recorded from North America previously, while two others, P. nemorale and P. succulentum, had not been listed in the North American bryoflora for 50 years. One taxon is new for the U.S.A. – P. succulentum f. propaguliferum. Here I provide detailed descriptions of the anatomical and morphological features of the recorded taxa along with photographic documentation of their most important characteristics. I also summarize their known distributions in North America and ecological preferences and provide a key for their identification.

Aceroryctes dulcis, a new palaeoryctid (Mammalia, Eutheria) from the early Eocene of the Wasatch Formation of southwestern Wyoming, USA

2014 ◽  
Vol 51 (10) ◽  
pp. 919-926 ◽  
Author(s):  
Brian D. Rankin ◽  
Patricia A. Holroyd
Keyword(s):  
Phylogenetic Analysis ◽  
North America ◽  
North American ◽  
Main Body ◽  
Early Eocene ◽  
New Findings ◽  
Genus Richness ◽  
Land Mammal

The Palaeoryctidae are a group of small-bodied, likely insectivorous mammals known principally from the Paleocene and early Eocene (from approximately 65 to 53 Ma) of North America. Here we report on a new palaeoryctid from the early Eocene (early Wasatchian (Wa3) North American Land Mammal Age) Main Body of the Wasatch Formation, Washakie Basin, near Bitter Creek station in southwestern Wyoming, USA. Acerorcytes dulcis gen. et sp. nov. is unique among palaeoryctids in having a double-rooted P2 with a small anterior cusp, P3 with pronounced para- and metastylar cusps and a reduced but conspicuous metacone, P4 with a weakly developed metacone and an anteroposteriorly compressed protocone, and M1-2 with deep ectoflexus and a sharp metastylar blade. A phylogenetic analysis based on 32 dental characters of the nine known North American palaeoryctid species, including Aceroryctes dulcis, recovered eight equally parsimonious cladograms. Similar to prior studies, the analysis suggests that the genus Palaeoryctes is non-monophyletic, with Palaeoryctes cruoris and Aaptoryctes ivyi closely related. Aceroryctes dulcis is grouped with Ottoryctes winkleri and positioned in a more inclusive clade with Eoryctes melanus; the remaining palaeoryctid taxa, including Lainoryctes youzwyshyni, are part of an unresolved polytomy. These new findings indicate that early Eocene palaeoryctids were more diverse than previously thought, with genus richness during the early Eocene at least as great as that during the middle Paleocene.

Taxonomy of Venezuelan white-tailed deer (Odocoileus, Cervidae, Mammalia), based on cranial and mandibular traits

1999 ◽  
Vol 77 (4) ◽  
pp. 632-645 ◽  
Author(s):  
Misael Molina ◽  
Jesús Molinari
Keyword(s):  
North America ◽  
North American ◽  
Single Species ◽  
Distinct Species ◽  
South American ◽  
Single Group ◽  
Caribbean Coast ◽  
The Caribbean ◽  
Andean Highlands ◽  
North And South

North and South American white-tailed deer are deemed to be a single species, Odocoileus virginianus. We used principal components and cluster analyses to compare crania and mandibles of Venezuelan and North American forms. We found that (1) Venezuelan and North American Odocoileus differ greatly from each other; (2) differentiation of groups within Venezuela exceeds that within North America; (3) the most divergent Venezuelan Odocoileus are those from Margarita Island and the Mérida Andean highlands; (4) the Margaritan Odocoileus does not differ in mandibular shape from its lowland congeners, but differs appreciably from other Venezuelan Odocoileus in having smaller mandibles and in cranial-mandibular characters; (5) the Mérida Andean Odocoileus contrasts markedly with other Venezuelan congeners in mandibular shape and cranial characters; (6) the remaining Venezuelan Odocoileus constitute a single group; (7) within this group, individuals from the Caribbean coast have larger mandibles and differ in some cranial characters. Thus, we propose that (a) Venezuelan and other Neotropical Odocoileus are not conspecific with O. virginianus; (b) Margaritan and Andean forms are distinct species: Odocoileus margaritae and Odocoileus lasiotis, respectively; (c) the remaining Venezuelan forms must be included within one species, Odocoileus cariacou; (d) Caribbean coast Odocoileus may represent an undescribed subspecies of O. cariacou.

scholarly journals Eocene North American Testudinidae and Geoemydidae (Reptilia, Testudines): A Re-Evaluation of Their Alpha Taxonomy, Ecology, and Origin

Proceedings ◽  
2019 ◽  
Vol 24 (1) ◽  
pp. 24 ◽  
Author(s):  
Asher J. Lichtig ◽  
Steven E. Jasinski ◽  
Spencer G. Lucas
Keyword(s):  
North America ◽  
North American ◽  
Early Eocene ◽  
New Material ◽  
Land Mammal

We describe new material, including juvenile specimens, of Hadrianus corsoni, Hadrianus majusculus, Echmatemys haydeni, and Echmatemys naomi. Testudinidae evolved in North America from one of the geoemydid-like forms in the genus Echmatemys, which have their lowest stratigraphic occurrence in the earliest Wasatchian North American land mammal “age” (early Eocene, Ypresian).

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