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.

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.

Osteology and phylogeny of small-bodied hadrosauromorphs from an end-Cretaceous marine assemblage

2020 ◽  
Vol 191 (1) ◽  
pp. 180-200
Author(s):  
Chase Doran Brownstein
Keyword(s):  
New Jersey ◽  
North America ◽  
Late Cretaceous ◽  
Eastern Coast ◽  
Eastern North America ◽  
Post Mortem ◽  
Western North America ◽  
Dominant Group ◽  
Dinosaur Extinction ◽  
Depositional Setting

Abstract The timing of non-avian dinosaur decline is one of the most debated subjects in dinosaur palaeontology. Dinosaur faunas from the last few million years of the Mesozoic appear far less diverse than those from earlier in the Cretaceous, a trend that could suggest non-avian dinosaur extinction occurred gradually. However, the limited nature of the latest Cretaceous dinosaur record outside western North America has obscured patterns in dinosaur diversity just before the extinction. Here, I describe two associated skeletons and several isolated fossils recovered from the New Egypt Formation of New Jersey, a latest Maastrichtian unit that underlies the K–Pg boundary. The larger skeleton appears to be a small-bodied adult from a lineage outside Hadrosauridae, the dominant group of these animals during the Maastrichtian, that persisted along the eastern coast of North America. Smaller specimens are identifiable as juvenile hadrosauromorphs. These results substantiate an important assemblage of herbivorous dinosaurs from the poorly-known Cretaceous of eastern North America. The marine depositional setting for these skeletons demonstrates that proposed ecosystem preferences among hadrosauromorphs may be biased by post-mortem transportation, and the adult skeleton has implications for assessing the proposed relictual nature of Late Cretaceous eastern North American vertebrates.

scholarly journals Theropod hindlimbs with feeding and other traces reveal ecosystem dynamics in the Maastrichtian of eastern North America

2018 ◽  
Author(s):  
Chase D Brownstein
Keyword(s):  
New Jersey ◽  
North America ◽  
Atlantic Coastal Plain ◽  
Ecosystem Dynamics ◽  
Eastern North America ◽  
Terrestrial Vertebrate ◽  
Past Life ◽  
Atlantic Coastal ◽  
Tibia Shaft ◽  
Tooth Marks

Direct documentation of the ecology of past life is often rare when the fossil record is comparatively poor, as in the case of the terrestrial fauna of the Maastrichtian of eastern North America. Here, I describe a femur and partial tibia shaft assignable to theropods from the Maastrichtian Big Brook locality of New Jersey. The former, identifiable to a previously undetected morphotype of large ornithomimosaur, bears several scrapes identifiable as the feeding traces of sharks, adding to the collection of terrestrial vertebrate remains bearing such marks from the state. The latter is littered with tooth marks and punctures from possibly multiple crocodyliform individuals, the first documented occurrence of such traces on dinosaur bone from the Maastrichtian of the Atlantic Coastal Plain. Additionally, its surface is dotted with likely traces of invertebrates, revealing a microcosm of biological interaction from the Maastrichtian New Jersey shoreline. Previously, the massive Campanian crocodylian taxon Deinosuchus rugosus and the slightly smaller Cenomanian-age Texas crocodyliform Deltasuchus motherali have been shown as important drivers of terrestrial vertebrate taphonomy in eastern North America. The report of crocodyliform bite marks on the ornithomimosaur metatarsal shaft in this manuscript reveals that crocodylians continued to play role in the taphonomy of large dinosaurs in eastern North America through the end of the Mesozoic. The preserved invertebrate traces add to the sparse record of their traces on dinosaur bone, and the presence of shark scrapes on the femur supports the “bloat-and-float” model of terrestrial vertebrate fossil deposition in eastern North America.

Species of Cortinarius subgenus Leprocybe, sections Orellani and Limonei, in North America

1994 ◽  
Vol 72 (4) ◽  
pp. 520-532 ◽  
Author(s):  
R. G. Thorn ◽  
D. W. Malloch
Keyword(s):  
North America ◽  
Morphological Characters ◽  
The Other ◽  
Mushroom Poisoning ◽  
Eastern North America ◽  
Similar Species ◽  
Western North America ◽  
Genetic Studies ◽  
Rdna Sequences ◽  
Fluorescent Compounds

Descriptions and a key are provided to seven species of Cortinarius subg. Leprocybe, sect. Orellani and Limonei, that are found in North America, namely C. callisteus (synonym C. croceocolor), C. distans var. olympianus, C. gentilis (synonym C. confusus), C. limoneus (synonym C. whiteae), C. morrisii, C. rainierensis, and C. speciosissimus. Of these, C. rainierensis and C. speciosissimus were previously shown to contain the nephrotoxin orellanine. Reports of C. orellanus from North America were based on misidentifications of C. uliginosus or similar species of subg. Dermocybe. There are no apparent morphological features to distinguish C. speciosissimus, which has been found in eastern North America, from C. rainierensis, which is known only from the state of Washington in western North America, or from C. orellanoides, which was described from France. Since morphological characters were found for the distinction of sibling species discovered by biochemical and genetic studies in other genera, including Armillaria, we prefer not to accept or suggest the synonymy of these taxa until neotypes or lectotypes are selected for C. croceocolor and C. rubellus and these specimens are compared with types of the other available names using chromatography of fluorescent compounds or rDNA sequences. Key words: biosystematics, mushroom poisoning, orellanine.

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.

FIRST RECORD OF STRONGYGASTER TRIANGULIFERA (LOEW) (DIPTERA: TACHINIDAE) AS A PARASITOID OF HARMONIA AXYRIDIS (PALLAS) (COLEOPTERA: COCCINELLIDAE) IN WESTERN NORTH AMERICA

1998 ◽  
Vol 130 (6) ◽  
pp. 905-906 ◽  
Author(s):  
P. Katsoyannos ◽  
M.T. Aliniazee
Keyword(s):  
North Carolina ◽  
North America ◽  
Harmonia Axyridis ◽  
First Record ◽  
The Other ◽  
Coleomegilla Maculata ◽  
Eastern North America ◽  
Indigenous Species ◽  
Western North America ◽  
Harmonia Axyridis Pallas

The parasitic tachinid fly Strongygaster triangulifera (Loew) is widely distributed in North America (Stone et al. 1965). It parasitizes several Coleoptera and sometimes species of other orders such as Lepidoptera, Dermaptera, and Hemiptera (Sabrosky and Braun 1970). Existing records of S. triangulifera found in coccinellid hosts are from eastern North America. One describes low parasitization levels (<1%) in two indigenous species, Coccinella trifasciata perplexa Mulsant and Coleomegilla maculata lengi Timberlake, in Ontario, Canada (Smith 1960). The other existing record describes fluctuating parasitization levels (3.0–31.1% in 1993 and 0–6.5% in 1994) in the exotic species Harmonia axyridis (Pallas) in North Carolina and Virginia (Nalepa et al. 1996).

scholarly journals Theropod hindlimbs with feeding and other traces reveal ecosystem dynamics in the Maastrichtian of eastern North America

2018 ◽  
Author(s):  
Chase D Brownstein
Keyword(s):  
New Jersey ◽  
North America ◽  
Atlantic Coastal Plain ◽  
Ecosystem Dynamics ◽  
Eastern North America ◽  
Terrestrial Vertebrate ◽  
Past Life ◽  
Atlantic Coastal ◽  
Tibia Shaft ◽  
Tooth Marks

Direct documentation of the ecology of past life is often rare when the fossil record is comparatively poor, as in the case of the terrestrial fauna of the Maastrichtian of eastern North America. Here, I describe a femur and partial tibia shaft assignable to theropods from the Maastrichtian Big Brook locality of New Jersey. The former, identifiable to a previously undetected morphotype of large ornithomimosaur, bears several scrapes identifiable as the feeding traces of sharks, adding to the collection of terrestrial vertebrate remains bearing such marks from the state. The latter is littered with tooth marks and punctures from possibly multiple crocodyliform individuals, the first documented occurrence of such traces on dinosaur bone from the Maastrichtian of the Atlantic Coastal Plain. Additionally, its surface is dotted with likely traces of invertebrates, revealing a microcosm of biological interaction from the Maastrichtian New Jersey shoreline. Previously, the massive Campanian crocodylian taxon Deinosuchus rugosus and the slightly smaller Cenomanian-age Texas crocodyliform Deltasuchus motherali have been shown as important drivers of terrestrial vertebrate taphonomy in eastern North America. The report of crocodyliform bite marks on the ornithomimosaur metatarsal shaft in this manuscript reveals that crocodylians continued to play role in the taphonomy of large dinosaurs in eastern North America through the end of the Mesozoic. The preserved invertebrate traces add to the sparse record of their traces on dinosaur bone, and the presence of shark scrapes on the femur supports the “bloat-and-float” model of terrestrial vertebrate fossil deposition in eastern North America.

NEW RECORDS OF OTIORHYNCHUS GERMAR SPECIES IN WESTERN NORTH AMERICA (COLEOPTERA: CURCULIONIDAE)

1991 ◽  
Vol 123 (6) ◽  
pp. 1395-1395 ◽  
Author(s):  
Robert S. Anderson
Keyword(s):  
North America ◽  
Natural History ◽  
New Records ◽  
Eastern North America ◽  
Western North America

Seventeen species of the genus Otiorhynchus are known to occur in North America (including Greenland) (O'Brien and Wibmer 1982; Wibmer and O'Brien 1989). Warner and Negley (1976) provide a key to 16 species (not including O. monticola Germar, since recorded from Greenland) and provide information on distribution and natural history. All species occurring on mainland North America are known to be introduced. Whereas some of the species have broad distributions in North America, for example O. ovatus (L.), others are known from only a few adjacent localities. Species such as O. singularis (L.) and O. sulcatus (F.) are found in both western and eastern North America but not in intervening areas. Such distributions likely represent separate introductions.

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