A Borophagine canid (Carnivora: Canidae: Borophaginae) from the middle Miocene Chesapeake Group of eastern North America

2015 ◽  
Vol 89 (6) ◽  
pp. 1082-1088
Author(s):  
Steven E. Jasinski ◽  
Steven C. Wallace
Keyword(s):  
North America ◽  
Fossil Record ◽  
Middle Miocene ◽  
Type Specimen ◽  
Distinct Species ◽  
Eastern North America ◽  
Northeastern North America ◽  
Second Molar ◽  
New Material ◽  
The One

AbstractA tooth recovered from the middle Miocene Choptank Formation (Chesapeake Group) of Maryland is identified as a new cynarctin borophagine (Canidae: Borophaginae: Cynarctina), here called Cynarctus wangi n. sp. The tooth, identified as a right upper second molar, represents the first carnivoran material reported from the Choptank Formation and part of a limited record of borophagine canids from eastern North America. As ?Cynarctus marylandica (Berry, 1938), another cynarctin borophagine from the older Calvert Formation, is known only from lower dentition, its generic affinities are uncertain. However, features of this new material are compared to features of ?C. marylandica through occlusal relationships, allowing for referral to a distinct species. Even so, the Choptank Formation material still offers two possible scenarios regarding its identification. In one, its geographic and stratigraphic provenance could imply that it belongs to ?C. marylandica. If this were correct, then the generic placement of ?C. marylandica would be correct and the taxon would be more derived than some other Cynarctus species in regard to hypocarnivory, and less derived than others. The second possibility, and the one believed to be most probable, is that a distinct cynarctin borophagine is present in the Chesapeake Group in strata younger than the type specimen of ?C. marylandica. This new borophagine canid expands the sparse fossil record of this group in northeastern North America and furthers our knowledge of the fossil record of terrestrial taxa in this region.

scholarly journals New records of theropods from the latest Cretaceous of New Jersey and the Maastrichtian Appalachian fauna

2019 ◽  
Vol 6 (11) ◽  
pp. 191206 ◽  
Author(s):  
Chase Doran Brownstein
Keyword(s):  
New Jersey ◽  
North America ◽  
Fossil Record ◽  
New Records ◽  
The Other ◽  
Eastern North America ◽  
Western North America ◽  
Northeastern North America ◽  
Terrestrial Vertebrate ◽  
Postcranial Remains

The faunal changes that occurred in the few million years before the Cretaceous–Palaeogene extinction are of much interest to vertebrate palaeontologists. Western North America preserves arguably the best fossil record from this time, whereas terrestrial vertebrate fossils from the eastern portion of the continent are usually limited to isolated, eroded postcranial remains. Examination of fragmentary specimens from the American east, which was isolated for the majority of the Cretaceous as the landmass Appalachia, is nonetheless important for better understanding dinosaur diversity at the end of the Mesozoic. Here, I report on two theropod teeth from the Mount Laurel Formation, a lower-middle Maastrichtian unit from northeastern North America. One of these preserves in detail the structure of the outer enamel and resembles the dentition of the tyrannosauroid Dryptosaurus aquilunguis among latest Cretaceous forms in being heavily mediolaterally compressed and showing many moderately developed enamel crenulations. Along with previously reported tyrannosauroid material from the Mt Laurel and overlying Cretaceous units, this fossil supports the presence of non-tyrannosaurid tyrannosauroids in the Campanian–Maastrichtian of eastern North America and provides evidence for the hypothesis that the area was still home to relictual vertebrates through the end of the Mesozoic. The other tooth is assignable to a dromaeosaurid and represents both the youngest occurrence of a non-avian maniraptoran in eastern North America and the first from the Maastrichtian reported east of the Mississippi. This tooth, which belonged to a 3–4 m dromaeosaurid based on size comparisons with the teeth of taxa for which skeletons are known, increases the diversity of the Maastrichtian dinosaur fauna of Appalachia. Along with previously reported dromaeosaurid teeth, the Mt Laurel specimen supports the presence of mid-sized to large dromaeosaurids in eastern North America throughout the Cretaceous.

BIOSYSTEMATIC STUDIES ON XANTHIUM: TAXONOMIC APPRAISAL AND ECOLOGICAL STATUS

1959 ◽  
Vol 37 (2) ◽  
pp. 173-208 ◽  
Author(s):  
Doris Löve ◽  
Pierre Dansereau
Keyword(s):  
North America ◽  
South America ◽  
Ecological Status ◽  
Distinct Species ◽  
Eastern North America ◽  
Flowering Response ◽  
Short Day ◽  
Stable Species ◽  
Enormous Variation

The following paper is an evaluation of the taxonomic and ecological status of the genus Xanthium L. A review of its systematics demonstrates that many so-called "species" described on material from Europe actually have their origin in America, except one, X. strumarium s. str., which seems to have a Mediterranean–European center of dispersal. Another conclusion drawn is that Xanthium consists of only two distinct species: X. spinosum L. and X. strumarium L. The former is a relatively stable species, the latter an enormously variable one readily subdivided into a number of minor taxonomic entities.Ecologically, in eastern North America at least, Xanthium is primarily a beach plant, which prefers open habitats and succumbs to crowding. The seeds are most often dispersed by water and wind. It enters easily into ruderal habitats, but only as long as these are open and unshaded.The generalized short-day flowering response in this genus supports our hypothesis that Xanthium has a tropical–subtropical origin, and we feel that it has its center in Central and/or South America, whence it has spread over the continents north and southward.There is no evidence for any sterility barriers separating the entities of X. strumarium, but we feel that an intense inbreeding with an occasional outbreeding is responsible for the enormous variation, often resulting in small, local, but unstable taxa.

scholarly journals How the past impacts the future: modelling the performance of evolutionarily distinct mammals through time

2019 ◽  
Vol 374 (1788) ◽  
pp. 20190210 ◽  
Author(s):  
D. J. Bennett ◽  
M. D. Sutton ◽  
S. T. Turvey
Keyword(s):  
Fossil Record ◽  
Distinct Species ◽  
Performance Impact ◽  
Deep Time ◽  
The Past ◽  
Living Fossils ◽  
Measuring Change ◽  
Molecular Phylogenetic ◽  
Time Changes ◽  
The One

How does past evolutionary performance impact future evolutionary performance? This is an important question not just for macroevolutionary biologists who wish to chart the phenomena that describe deep-time changes in biodiversity but also for conservation biologists, as evolutionarily distinct species—which may be deemed ‘low-performing’ in our current era—are increasingly the focus of conservation efforts. Contrasting hypotheses exist to account for the history and future of evolutionarily distinct species: on the one hand, they may be relicts of large radiations, potentially ‘doomed’ to extinction; or they may be slow-evolving, ‘living fossils’, likely neither to speciate nor go extinct; or they may be seeds of future radiations. Here, we attempt to test these hypotheses in Mammalia by combining a molecular phylogenetic supertree with fossil record occurrences and measuring change in evolutionary distinctness (ED) at different time slices. With these time slices, we modelled future ED as a function of past ED. We find that past evolutionary performance does indeed have an impact on future evolutionary performance: the most evolutionarily isolated clades tend to become more evolutionarily distinct with time, indicating that low-performing clades tend to remain low-performing throughout their evolutionary history. This article is part of a discussion meeting issue ‘The past is a foreign country: how much can the fossil record actually inform conservation?’

MOTHS OF THE SEMIOTHISA SIGNARIA COMPLEX (LEPIDOPTERA: GEOMETRIDAE)

1974 ◽  
Vol 106 (6) ◽  
pp. 569-621 ◽  
Author(s):  
Douglas C. Ferguson
Keyword(s):  
New Species ◽  
North America ◽  
Host Plants ◽  
Similar Species ◽  
Northeastern North America ◽  
Coniferous Trees ◽  
Two New Species ◽  
Industrial Melanism ◽  
The One ◽  
Main Center

AbstractThe signaria group of the genus Semiothisa is a complex of 10 extremely similar species, most of which are host-specific on certain genera of coniferous trees An eleventh species, S. sexmaculata, is also treated in this revision because of its close resemblance to members of the signaria complex, although its true affinity appears to be with the liturata–bisignata group. The species are described and illustrated, and their synonymy, distribution, variation and biology are discussed in detail, including an account of industrial melanism in a population of S. pinistrobata. Two new species names are proposed, and eight lectotypes designated. The main center of distribution is northeastern North America, and all of the known species except S. fuscaria occur on this continent. The one Holarctic species, S. signaria, which is generally the commonest in collections, also has the widest range of host plants, feeding on at least six genera of coniferous trees.

scholarly journals Caliciopsis moriondi, a new species for a fungus long confused with the pine pathogen C. pinea

MycoKeys ◽  
2020 ◽  
Vol 73 ◽  
pp. 87-108
Author(s):  
Duccio Migliorini ◽  
Nicola Luchi ◽  
Alessia Lucia Pepori ◽  
Francesco Pecori ◽  
Chiara Aglietti ◽  
...  
Keyword(s):  
New Species ◽  
North America ◽  
Pinus Radiata ◽  
Phylogenetic Analyses ◽  
Distinct Species ◽  
Integrative Approach ◽  
Eastern North America ◽  
Pathogenic Species ◽  
Eastern Usa ◽  
A New Species

The genus Caliciopsis (Eurotiomycetes, Coryneliales) includes saprobic and plant pathogenic species. Caliciopsis canker is caused by Caliciopsis pinea Peck, a species first reported in the 19th century in North America. In recent years, increasing numbers of outbreaks of Caliciopsis canker have been reported on different Pinus spp. in the eastern USA. In Europe, the disease has only occasionally been reported causing cankers, mostly on Pinus radiata in stressed plantations. The aim of this study was to clarify the taxonomy of Caliciopsis specimens collected from infected Pinus spp. in Europe and North America using an integrative approach, combining morphology and phylogenetic analyses of three loci. The pathogenicity of the fungus was also considered. Two distinct groups were evident, based on morphology and multilocus phylogenetic analyses. These represent the known pathogen Caliciopsis pinea that occurs in North America and a morphologically similar, but phylogenetically distinct, species described here as Caliciopsis moriondisp. nov., found in Europe and at least one location in eastern North America. Caliciopsis moriondi differs from C. pinea in various morphological features including the length of the ascomata, as well as their distribution on the stromata.

scholarly journals Redescription of Arundel formation Ornithomimosaur material and a reinterpretation of Nedcolbertia justinhofmanni as an “Ostrich Dinosaur”: Biogeographic implications

2016 ◽  
Author(s):  
Chase Doran Brownstein
Keyword(s):  
United States ◽  
North America ◽  
Early Cretaceous ◽  
Fossil Record ◽  
East Coast ◽  
The United States ◽  
Eastern North America ◽  
New Taxon ◽  
Western North America ◽  
The Past

The fossil record of dinosaurs from the Early Cretaceous of eastern North America is scant, and only a few sediments to the east of the continent are fossiliferous. Among them is the Arundel Formation of the east coast of the United States, which has produced among the best dinosaur faunas known from the Early Cretaceous of eastern North America. The diverse dinosaur fauna of this formation has been thoroughly discussed previously, but few of the dinosaur species originally described from the Arundel are still regarded as valid genera. Much of the Arundel material is in need of review and redescription. Among the fossils of dinosaurs from this formation are those referred to ornithomimosaurs. Here, I redescribe ornithomimosaur remains from the Arundel Formation which may warrant the naming of a new taxon of dinosaur. These remains provide key information on the theropods of the Early Cretaceous of Eastern North America. The description of the Arundel material herein along with recent discoveries of basal ornithomimosaurs in the past 15 years has allowed for comparisons with the coelurosaur Nedcolbertia justinhofmanni, suggesting the latter animal was a basal ornithomimosaurian dinosaur rather than a “generalized” coelurosaur. Comparisons between the Arundel ornithomimosaur and similar southeast Asian ornithomimosaurian material as well as ornithomimosaur remains from western North America suggest that a lineage of ornithomimosaurs with a metatarsal condition intermediate between that of basal and derived ornithomimosaurs was present through southeast Asia into North America, in turn suggesting that such animals coexisted with genera having a more primitive metatarsal morphology as seen in N. justinhofmanni.

The taxonomic status of Merychippus insignis Leidy

1986 ◽  
Vol 60 (6) ◽  
pp. 1277-1280 ◽  
Author(s):  
Robert L. Evander
Keyword(s):  
South Dakota ◽  
Fossil Record ◽  
Type Species ◽  
Middle Miocene ◽  
Taxonomic Status ◽  
Type Specimen ◽  
Ancestral Group ◽  
The Many

The genus Merychippus was erected by Leidy (1857), who named as the type species Merychippus insignis. The type specimen of M. insignis is an immature and incomplete maxilla containing a broken dp2 and a dp3. The type comes from the Bijou Hills of South Dakota, probably from the Barstovian (middle Miocene) Fort Randall Formation of South Bijou Hill in Charles Mix County (Skinner and Taylor, 1967), but possibly from the overlying undifferentiated Ogallala Formation, or possibly from North Bijou Hill in Brule County. Despite this enigmatic type, the species M. insignis has frequently been identified in the fossil record, and the genus Merychippus has grown to include all mesodont horses (Stirton, 1940). Conceptually, the taxon Merychippus is considered a horizontal grade rather than a vertical clade (Simpson, 1945, p. 18). As a horizontal concept, the genus Merychippus derived importance as the ancestral group for the many Mio-Pliocene lineages of hypsodont horses. Today, as horse classification is remodeled along cladistic lines, the taxon Merychippus derives importance from its early naming. Several distinctive horse clades extend upward from a middle Miocene radiation (Stirton, 1940; Quinn, 1955). If M. insignis can be placed within one of these clades, then it is likely that the clade will bear the generic nomen Merychippus because of the antiquity of the name.

REVISION OF THE CHIGGER-LIKE LARVAE OF THE GENERA NEOTROMBIDIUM LEONARDI AND MONUNGUIS WHARTON, WITH A REDEFINITION OF THE SUBFAMILY NEOTROMBIDIINAE FEIDER IN THE TROMBIDIIDAE (ACARINA: PROSTIGMATA)

1971 ◽  
Vol 103 (11) ◽  
pp. 1557-1590 ◽  
Author(s):  
E. E. Lindquist ◽  
P. H. Vercammen-Grandjean
Keyword(s):  
New Species ◽  
North America ◽  
New Combination ◽  
Eastern North America ◽  
The Family ◽  
Family Level ◽  
Caribbean Area ◽  
History Of ◽  
The Caribbean ◽  
The One

AbstractThe trombidiid subfamily Neotrombidiinae Feider is re-established and redefined, based primarily on larval characters but also on adult characters. It is closely related to the trombidiid Trombellinae on the one hand and to the Leeuwenhoekidae on the other. It consists of two genera, namely Monunguis Wharton, which is monobasic and known only from the larva, and Neotrombidium Leonardi, with 13 described species of which 7 are known from the larva and 8 from the adult (the larva and adult of 2 species are correlated by rearings).The history of the family-level placement of this group, and the controversy over whether or not to recognize two genera, are reviewed. The characters that justify the separate recognition of Monunguis and Neotrombidium are enumerated.The larva of each of the following species of Neotrombidiinae is described, illustrated and keyed: Monunguis streblida Wharton from the Caribbean area, Neotrombidium barringunense Hirst from Australia, N. tricuspidum Borland from North America, N. tenuipes (Womersley) from Malaya, N. samsinaki (Daniel) new combination from central Europe, N. anuroporum new species from Central America, N. bengalense new species from India, and N. tenebrione new species from eastern North America. Six other species of this group, known only from the adult, are listed separately but are not treated taxonomically here.The larvae of Neotrombidiinae parasitize adult insects: those of Monunguis are hyperparasites on streblid flies whereas those of Neotrombidium are ectoparasites of cerambycid, clerid, elaterid, and tenebrionid beetles that pass part of their life history under the bark of trees.In the Microtrombidiinae, Camerotrombidium Thor is noted as the valid replacement name for the preoccupied Ottonia Kramer.

ECOLOGICAL STUDY OF THE PEAT BOGS OF EASTERN NORTH AMERICA: I. STRUCTURE AND EVOLUTION OF VEGETATION

1952 ◽  
Vol 30 (4) ◽  
pp. 490-520 ◽  
Author(s):  
Pierre Dansereau ◽  
Fernando Segadas-Vianna
Keyword(s):  
North America ◽  
Ecological Study ◽  
Peat Bogs ◽  
Eastern North America ◽  
General Outline ◽  
Geographical Scale ◽  
Biological Aspects ◽  
The One ◽  
Principal Elements ◽  
Evolution Of Vegetation

It is attempted to clearly distinguish between bogs on the one hand and swamps and marshes on the other. The principal elements and factors are listed in Eastern North America where bogs are frequent. This first paper attempts a general outline of the dynamics of bog vegetation in this region and describes the structures of the communities involved. The biotope is considered the smallest piece in the association mosaic and its physical and biological aspects are emphasized. Two recent systems (Küchler's and Dansereau's) are applied to individualize the most important and widespread synecological units. Further studies involving climatic relationships on a geographical scale and phytosociological measurements at the quadrat level will permit a refocusing of some of the phenomena which are described and interpreted here.

Taxonomic revision of the Carex stricta (Cyperaceae) complex in eastern North America

1989 ◽  
Vol 67 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Lisa A. Standley
Keyword(s):  
North America ◽  
Chromosome Numbers ◽  
Taxonomic Revision ◽  
Distinct Species ◽  
North American Species ◽  
Eastern North America ◽  
Distribution Maps ◽  
Carex Stricta ◽  
Morphological Studies ◽  
Infraspecific Taxa

Morphological studies of the Carex stricta complex confirm hypotheses based on chromosome numbers that there are three distinct species in eastern North America, Carex stricta, C. emoryi, and C. haydenii, but they do not indicate the existence of any distinct infraspecific taxa. These species are compared phenetically with all other North American species of section Phacocystis. Results indicate that the three species examined here do not form a closely related subgroup within the section as suggested by previous authors. Distribution maps, descriptions, and synonomy are provided for these species, and a complete key to the species of section Phacocystis in eastern North America is given.

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