scholarly journals Notes on the cheek region of the Late Jurassic theropod dinosaur Allosaurus

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e8493
Author(s):  
Serjoscha W. Evers ◽  
Christian Foth ◽  
Oliver W.M. Rauhut
Keyword(s):  
North America ◽  
19Th Century ◽  
Late Jurassic ◽  
Morrison Formation ◽  
Late 19Th Century ◽  
Theropod Dinosaur ◽  
European Species ◽  
Theropod Dinosaurs ◽  
The Common ◽  
Iconic Status

Allosaurus, from the Late Jurassic of North America and Europe, is a model taxon for Jurassic basal tetanuran theropod dinosaurs. It has achieved an almost iconic status due to its early discovery in the late, 19th century, and due to the abundance of material from the Morrison Formation of the western U.S.A., making Allosaurus one of the best-known theropod taxa. Despite this, various aspects of the cranial anatomy of Allosaurus are surprisingly poorly understood. Here, we discuss the osteology of the cheek region, comprised by the jugal, maxilla, and lacrimal. This region of the skull is of importance for Allosaurus taxonomy and phylogeny, particularly because Allosaurus has traditionally been reconstructed with an unusual cheek configuration, and because the European species Allosaurus europaeus has been said to be different from North American material in the configuration of these bones. Based on re-examination of articulated and disarticulated material from a number of repositories, we show that the jugal participates in the antorbital fenestra, contradicting the common interpretation. The jugal laterally overlies the lacrimal, and forms an extended antorbital fossa with this bone. Furthermore, we document previously unrecorded pneumatic features of the jugal of Allosaurus.

scholarly journals Cranial anatomy of Allosaurus jimmadseni, a new species from the lower part of the Morrison Formation (Upper Jurassic) of Western North America

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e7803 ◽  
Author(s):  
Daniel J. Chure ◽  
Mark A. Loewen
Keyword(s):  
New Species ◽  
North America ◽  
Phylogenetic Analyses ◽  
Upper Jurassic ◽  
Morrison Formation ◽  
Ventral Margin ◽  
Western North America ◽  
Theropod Dinosaur ◽  
Theropod Dinosaurs ◽  
A New Species

Allosaurus is one of the best known theropod dinosaurs from the Jurassic and a crucial taxon in phylogenetic analyses. On the basis of an in-depth, firsthand study of the bulk of Allosaurus specimens housed in North American institutions, we describe here a new theropod dinosaur from the Upper Jurassic Morrison Formation of Western North America, Allosaurus jimmadseni sp. nov., based upon a remarkably complete articulated skeleton and skull and a second specimen with an articulated skull and associated skeleton. The present study also assigns several other specimens to this new species, Allosaurus jimmadseni, which is characterized by a number of autapomorphies present on the dermal skull roof and additional characters present in the postcrania. In particular, whereas the ventral margin of the jugal of Allosaurus fragilis has pronounced sigmoidal convexity, the ventral margin is virtually straight in Allosaurus jimmadseni. The paired nasals of Allosaurus jimmadseni possess bilateral, blade-like crests along the lateral margin, forming a pronounced nasolacrimal crest that is absent in Allosaurus fragilis.

scholarly journals New data towards the development of a comprehensive taphonomic framework for the Late Jurassic Cleveland-Lloyd Dinosaur Quarry, Central Utah

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3368 ◽  
Author(s):  
Joseph E. Peterson ◽  
Jonathan P. Warnock ◽  
Shawn L. Eberhart ◽  
Steven R. Clawson ◽  
Christopher R. Noto
Keyword(s):  
Late Jurassic ◽  
Data Sets ◽  
Morrison Formation ◽  
Multiple Sources ◽  
Theropod Dinosaurs ◽  
The Matrix ◽  
Significant Step ◽  
Primary Driver ◽  
History Of ◽  
Bone Fragments

The Cleveland-Lloyd Dinosaur Quarry (CLDQ) is the densest deposit of Jurassic theropod dinosaurs discovered to date. Unlike typical Jurassic bone deposits, it is dominated by the presence ofAllosaurus fragilis. Since excavation began in the 1920s, numerous hypotheses have been put forward to explain the taphonomy of CLDQ, including a predator trap, a drought assemblage, and a poison spring. In an effort to reconcile the various interpretations of the quarry and reach a consensus on the depositional history of CLDQ, new data is required to develop a robust taphonomic framework congruent with all available data. Here we present two new data sets that aid in the development of such a robust taphonomic framework for CLDQ. First, x-ray fluorescence of CLDQ sediments indicate elevated barite and sulfide minerals relative to other sediments from the Morrison Formation in the region, suggesting an ephemeral environment dominated by periods of hypereutrophic conditions during bone accumulation. Second, the degree of abrasion and hydraulic equivalency of small bone fragments dispersed throughout the matrix were analyzed from CLDQ. Results of these analyses suggest that bone fragments are autochthonous or parautochthonous and are derived from bones deposited in the assemblage rather than transported. The variability in abrasion exhibited by the fragments is most parsimoniously explained by local periodic re-working and re-deposition during seasonal fluctuations throughout the duration of the quarry assemblage. Collectively, these data support previous interpretations that the CLDQ represents an attritional assemblage in a poorly-drained overbank deposit where vertebrate remains were introduced post-mortem to an ephemeral pond during flood conditions. Furthermore, while the elevated heavy metals detected at the Cleveland-Lloyd Dinosaur Quarry are not likely the primary driver for the accumulation of carcasses, they are likely the result of multiple sources; some metals may be derived from post-depositional and diagenetic processes, and others are potentially produced from an abundance of decomposing vertebrate carcasses. These new data help to support the inferred depositional environment of the quarry as an ephemeral pond, and represent a significant step in understanding the taphonomy of the bonebed and Late Jurassic paleoecology in this region.

scholarly journals Monogenean parasites of Lepomis gibbosus Linnaeus introduced into the River Durance, France

2015 ◽  
Vol 52 (4) ◽  
pp. 323-330 ◽  
Author(s):  
L. Havlátová ◽  
M. Ondračková ◽  
I. Přikrylová
Keyword(s):  
North America ◽  
19Th Century ◽  
Parasite Species ◽  
Lepomis Gibbosus ◽  
Late 19Th Century ◽  
First Time

Summary The pumpkinseed, Lepomis gibbosus Linnaeus (Centrarchidae), was introduced into the Europe from North America in late 19th century. In this study, we examine monogenean parasites of L. gibbosus from the River Durance in France. We found seven parasite species introduced together with the host: Actinocleidus recurvatus, A. oculatus, Onchocleidus similis, O. dispar, O. acer, Cleidodiscus robustus (Ancyrocephalidae) and Gyrodactylus macrochiri (Gyrodactylidae). Early diporpa (Diplozoidae), accidentally attached to the gills, represent a single parasite species acquired within the area of introduction. Three species, O. acer, C. robustus and G. macrochiri, are reported from Europe for the first time.

scholarly journals A Late Jurassic salamander (Amphibia: Caudata) from the Morrison Formation of North America

2005 ◽  
Vol 143 (4) ◽  
pp. 599-616 ◽  
Author(s):  
S. E. EVANS ◽  
C. LALLY ◽  
D. C. CHURE ◽  
A. ELDER ◽  
J. A. MAISANO
Keyword(s):  
North America ◽  
Late Jurassic ◽  
Morrison Formation

Dwarf Snapdragon – The Railroad Weed

1991 ◽  
Vol 5 (2) ◽  
pp. 467-468 ◽  
Author(s):  
Robert M. Arnold
Keyword(s):  
North America ◽  
19Th Century ◽  
Mediterranean Region ◽  
Marked Decrease ◽  
Late 19Th Century ◽  
The Mediterranean

Believed native to the Mediterranean region, dwarf snapdragon [Chaenorrhinum minus (L.) Lange ♯ CHNMI] was introduced into North America in the late 19th century. Since its introduction, it has spread, mainly along railroad lines, to at least 30 states as far west as Kansas and Nebraska. Increased use of herbicides by railroad companies has resulted in a marked decrease in its abundance in recent years.

scholarly journals Probable basal allosauroid from the early Middle Jurassic Cañadón Asfalto Formation of Argentina highlights phylogenetic uncertainty in tetanuran theropod dinosaurs

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Oliver W. M. Rauhut ◽  
Diego Pol
Keyword(s):  
Middle Jurassic ◽  
Late Jurassic ◽  
Evolutionary History ◽  
Morphological Evolution ◽  
New Taxon ◽  
Rapid Radiation ◽  
Theropod Dinosaurs ◽  
Extinction Event ◽  
The Common ◽  
Early Radiation

AbstractTetanurae, the most successful clade of theropod dinosaurs, including modern birds, split into three major clades early in their evolutionary history: Megalosauroidea, Coelurosauria, and Allosauroidea. The oldest tetanurans occur in the earliest Middle Jurassic, but the early fossil record of the clade is still poor. Here we report one of the oldest known and most complete pre-Late Jurassic tetanuran, the probable allosauroid Asfaltovenator vialidadi gen. et sp. nov., which has an unusual character combination, uniting features currently considered to be apomorphic of different tetanuran lineages. A phylogenetic analysis resulted in a monophyletic Carnosauria (Allosauroidea + Megalosauroidea), and the inclusion of the new taxon significantly changes topology within carnosaurs. The analysis shows concentrated homoplasy in proximal nodes at the base of Tetanurae, and a temporal peak at the Pliensbachian-Toarcian extinction event, recently identified as a potential driver of tetanuran radiation. These results highlight the complex morphological evolution in the early radiation of tetanuran theropods, in which convergences and parallelisms were extremely common. This pattern seems to be a common feature in rapid radiation events of major clades of vertebrates and might explain the common difficulties to unravel phylogenetic relationships of important lineages at the base of major clades.

scholarly journals African Aphididae

1914 ◽  
Vol 4 (4) ◽  
pp. 313-337 ◽  
Author(s):  
Fred. V. Theobald
Keyword(s):  
North America ◽  
World Wide ◽  
Wide Distribution ◽  
African Continent ◽  
Eriosoma Lanigerum ◽  
European Species ◽  
Important Group ◽  
Nursery Stock ◽  
The Common ◽  
Trees And Shrubs

Our knowledge of the Aphididae of Africa is as yet very limited, this important group of insects having been but little studied, except in Europe and North America. At present only thirty-five species are recorded for the whole African continent, about the number one can collect in a single afternoon in one's own garden in England. It will be noticed that several common European species are recorded, and that they are as destructive in Africa as in Europe, such as the Common Cabbage Aphis (A. brassicae) and the Ribes and Lettuce Aphis (Rhopalosiphum lactucae). Several others occur which have a world-wide distribution, such as the Black Peach Aphis (Aphis persicae), and the Woolly Aphis (Eriosoma lanigerum), doubtless having been distributed on nursery stock, the former as ova and the latter as adults. Fuller has reported destroying and fumigating strawberry plants attacked by Aphis sent from Europe, and Lounsbury records the presence of Apple Aphis eggs on imported stock. Undoubtedly these insects are constantly being distributed from country to country with imported plants, trees and shrubs.

scholarly journals Samuel Wilmot, Fish Culture, and Recreational Fisheries in late 19th century Ontario

2009 ◽  
Vol 30 (1) ◽  
pp. 75-90 ◽  
Author(s):  
William Knight
Keyword(s):  
North America ◽  
19Th Century ◽  
Fish Culture ◽  
Commercial Fisheries ◽  
Recreational Fisheries ◽  
Government Officials ◽  
Late 19Th Century ◽  
Inland Fisheries ◽  
Game Fish ◽  
Comprehensive Programs

Abstract Historians have shown that fish culturists and anglers enjoyed a mutually beneficial relationship in 19th century North America. Sharing interests in producing and protecting fish for recreation, the two groups supported emerging regimes of fisheries administration and fish culture that privileged angling and game fish species. In Ontario, it has been argued that anglers achieved control of inland fisheries with help from state fish culturist Samuel Wilmot who, as a sportsman, shared anglers' recreational perspective. A closer look at Wilmot and fish culture in late 19th century Ontario, however, reveals a more complex struggle over recreational fisheries administration. I show that game fish culture under Wilmot was subordinated to fish culture programs that supported the Great Lakes commercial fisheries. Indeed, Wilmot resisted anglers' refraining of Ontario's fisheries as a private recreational resource. By the 1890s, however, this position was unpopular with Ontario's anglers and government officials, who demanded greater provincial control over recreational fisheries and fish culture. It was only after Wilmot's retirement in 1895 that game fish culture received higher priority in Ontario with both federal and provincial governments engaging in programs of wild bass transfers. In 1899, Ontario won a share of fisheries jurisdiction and established its first provincial fisheries administration, which laid the basis for more comprehensive programs of game fish culture in the 20th century.

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