Species New to Science

ABSTRACT

In the late 1960s, a team led by C.S. Churcher and A. MacS. Stalker collected over 1000 vertebrate fossils, mostly representing large herbivorous mammals, from bluffs along the South Saskatchewan River near Medicine Hat, Alberta, Canada. The records from this area also include the only documented case of the sabre-toothed cat Smilodon fatalis, but these specimens have not been described or illustrated, and therefore, their identification has never been verified. Here, all felid fossils recovered from the Medicine Hat bluffs are described and identified. We confirm the presence of the machairodontine S. fatalis and three additional taxa: the feline Lynx and the pantherines Panthera cf. P. atrox (American lion) and Panthera cf. P. spelaea (cave lion). Notably, this record of S. fatalis is its first confirmed occurrence in Canada and is a significant northerly range expansion, bringing the global distribution of this species in line with what is typical for a large felid. Should the tentative record of Panthera cf. P. spelaea be correct, this would represent its first occurrence in Alberta and a southeastern range extension, bringing it into the range of P. atrox. The possible presence of both P. atrox and P. spelaea suggests that Late Pleistocene pantherine biogeography in North America may be more complex than previously believed, particularly during relatively warm interglacial periods.

Keywords: Smilodon, Panthera, Lynx, sabre-toothed cat, lion, biogeography

ABSTRACT

Troodontids are known from Asia and North America, with the most complete specimens from the Jurassic of China and the Cretaceous of Mongolia. North American troodontids are poorly known, and specimens that have been described are isolated elements or partial skeletons with limited material. A new troodontid from the upper Dinosaur Park Formation (upper Campanian) is based on partial skulls, several vertebrae, ribs, gastralia, chevrons, a sacrum, partial pelvis, and partial fore and hind limbs. It is the largest troodontid known, with an estimated height of 180 cm and length of 350 cm. Like other troodontids, it possesses an elongated ambiens process and has a horizontal ventral margin of the postacetabular process. It differs from all other derived troodontids in that the slightly retroverted pubis has a shaft that curves anteroventrally. Some specimens from the Dinosaur Park Formation previously assigned to Troodon are reassigned to the new taxon, including multiple partial crania, an associated dentary and metatarsus, and a partial skeleton. Previously undescribed elements from the lower part of the Dinosaur Park Formation are assigned to the resurrected Stenonychosaurus inequalis. Distinct stratigraphic separation of Stenonychosaurus inequalis and the new taxon indicates a replacement in troodontid fauna, similar to the turnover of large ornithischians in the same formation. The new taxon is phylogenetically more closely related to Mongolian taxa, indicating the replacement of Stenonychosaurus may have been from an earlier Asian form immigrating into North America.

Aaron J. van der Reest and Philip J. Currie. 2017. Troodontids (Theropoda) from the Dinosaur Park Formation, Alberta, with A Description of A Unique New Taxon: Implications for Deinonychosaur Diversity in North America. Canadian Journal of Earth Sciences. 54; xx. DOI: 10.1139/cjes-2017-0031

 Introducing Latenivenatrix mcmasterae, new Troodontid from the DPF published in @CanJEarthSci this morning! Sorry Troodon formosus #invalid

 twitter.com/AaronVDReest/status/894926653855481856

Dino hips discovery unravels species riddle  bit.ly/2ulK0w6 via @ualberta @EurekAlert

Résumé: Les troodontidés connus proviennent d’Asie et d’Amérique du Nord, les spécimens les plus complets provenant du Jurassique de la Chine et du Crétacé de la Mongolie. Les troodontidés nord-américains sont peu connus et les spécimens décrits consistent en des éléments isolés ou des squelettes partiels représentés par une quantité limitée de matériau. Un nouveau troodontidé de la partie supérieure de la Formation de Dinosaur Park (Campanien supérieur) est basé sur des crânes partiels, plusieurs vertèbres, des côtes, une gastralia, des chevrons, un sacrum, un pelvis partiel et des membres antérieurs et postérieurs partiels. Il s’agit du plus grand troodontidé connu, dont la hauteur est estimée a` 180 cm et la longueur, a` 350 cm. À l’instar d’autres troodontidés, il présente un processus ambiens allongé et une marge ventrale horizontale du processus post-acétabulaire. Il se distingue de tous les autres troodontidés dérivés par son pubis légèrement rétroversé doté d’une diaphyse courbée antéroventralement. Certains spécimens de la Formation de Dinosaur Park auparavant attribués a` Troodon, incluant plusieurs crânes partiels, un os dentaire et un métatarse associés, ainsi qu’un squelette partiel, sont réaffectés au nouveau taxon. Des éléments non décrits auparavant de la partie inférieure de la Formation de Dinosaur Park sont affectés a` Stenonychosaurus inequalis. La séparation stratigraphique claire de Stenonychosaurus inequalis et du nouveau taxon indique un remplacement de la faune de troodontidés semblable au renouvellement des grands ornithischiens de la même formation. Le nouveau taxon est plus étroitement apparenté sur le plan phylogénétique aux taxons de Mongolie, ce qui indique que le remplacement de Stenonychosaurus pourrait être dû a` l’immigration en Amérique du Nord d’une forme asiatique plus ancienne.

Albertavenator curriei  Evans, Cullen, Larson & Rego, 2017 DOI: 10.1139/CJES-2017-0034

ABSTRACT

Troodontid material from the Maastrichtian of North America is extremely rare, beyond isolated teeth from microvertebrate sites. Here we describe troodontid frontals from the early Maastrichtian Horseshoe Canyon Formation (Horsethief Member). The most complete specimen, TMP 1993.105.0001, is notably foreshortened and robust when compared with numerous specimens referred to Troodon from the Dinosaur Park Formation, and exhibits several characteristics that distinguish it from other Late Cretaceous troodontids. Morphometric analyses reinforce shape differences between TMP 1993.105.0001 and other North American troodontids, and show that proportional differences are independent of size. We therefore erect a new taxon, Albertavenator curriei gen. et sp. nov., which is diagnosed by the following autapomorphies: (1) primary supraciliary foramen is truncated anteriorly by the lacrimal contact; (2) superficial (ectocranial) surface of the frontal proportionally shorter than all known troodontids, with a length to width ratio under 1.3; and (3) frontoparietal contact in which an enlarged lappet of the frontal extends medially to extensively overlap the lateral region of the anteromedial process of the parietal. Interestingly, tooth and jaw morphology from the single relatively complete dentary recovered from the Horseshoe Canyon cannot be distinguished from dentaries and teeth from the Dinosaur Park Formation. If the dentary and teeth from the Horsethief Member of the Horseshoe Canyon Formation prove to belong to A. curriei, extensive overlap in tooth morphology between the Dinosaur Park and Horseshoe Canyon formations reinforces the notion that tooth morphotypes do not exhibit strong correspondence to species alpha diversity, and may encompass multiple closely related taxa.

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“The bonebed was discovered by Danek Mozdzenski, an amateur fossil collector from Edmonton, on March 31, 1989 (Bell and Campione, 2014) and was initially excavated by the Royal Tyrrell Museum of Palaeontology in 1989 and 1991, during which time approximately 80 specimens were collected, including a partial articulated skeleton. The bonebed was reopened by the University of Alberta Laboratory for Vertebrate Palaeontology in 2006, and has since produced over 800 catalogued specimens.”

........

The Danek Edmontosaurus Bonebed: new insights on the Systematics, Biogeography, and Palaeoecology of Late Cretaceous Dinosaur Communities. Canadian Journal of Earth Sciences. 51(11) [November 2014] http://www.nrcresearchpress.com/toc/cjes/51/11

http://www.cdnsciencepub.com/news-and-events/press-releases/PR-CJES-Danek_Bonebed_Dec_2014.aspx

 The Danek Edmontosaurus Bonebed: new insights on the systematics, biogeography, and palaeoecology of Late Cretaceous dinosaur communities / Le lit d’ossements d’Edmontosaurus de Danek : le point sur la systématique, la biogéographie et la paléoécologie des populations de dinosaures du Crétacé tardif. Canadian Journal of Earth Sciences, 2014, 51(11): iii, 10.1139/cjes-2014-0148

Michael E. Burns, Clive Coy, Victoria M. Arbour, Philip J. Currie, Eva B. Koppelhus. 2014. The Danek Edmontosaurus Bonebed: new insights on the systematics, biogeography, and palaeoecology of Late Cretaceous dinosaur communities. Canadian Journal of Earth Sciences, 2014, 51(11): v-vii, 10.1139/cjes-2014-0217

David A. Eberth, Phil R. Bell. 2014. Stratigraphy of the Danek Bonebed (Upper Cretaceous Horseshoe Canyon Formation, central Alberta) and correlations with strata in the Drumheller and Grande Prairie regions. Canadian Journal of Earth Sciences, 2014, 51(11): 975-981, 10.1139/cjes-2014-0069

Angelica Torices, Gregory F. Funston, Shannon T. Kraichy, Philip J. Currie. 2014. The first appearance of Troodon in the Upper Cretaceous site of Danek Bonebed, and a reevaluation of troodontid quantitative tooth morphotypes. Canadian Journal of Earth Sciences, 2014, 51(11): 1039-1044, 10.1139/cjes-2014-0071

Phil R. Bell, Philip J. Currie. 2014. Albertosaurus (Dinosauria: Theropoda) material from an Edmontosaurus bonebed (Horseshoe Canyon Formation) near Edmonton: clarification of palaeogeographic distribution. Canadian Journal of Earth Sciences, 2014, 51(11): 1052-1057, 10.1139/cjes-2014-0050

Abstract

 Amongst the fossil material collected by the Sino-Soviet Expeditions (1959–1960) to the Alshan Desert, China, was a large, virtually complete ankylosaur skeleton. Gobisaurus domoculus gen. et sp. nov. closely resembles Shamosaurus scutatus, but is distinct in having an unfused basipterygoid–pterygoid contact and elongate premaxillary processes of the vomers. Although it is difficult to make a definitive taxonomic assignment without considering postcranial material, a preliminary phylogenetic analysis places Gobisaurus as the sister taxon of Shamosaurus, clustered as one of several successive outgroups of the Ankylosaurinae.

Systematic palaeontology

Dinosauria Owen 1842 | Ornithischia Seeley 1888

Ankylosauria Osborn 1923 | Ankylosauridae Brown 1908

Gobisaurus gen. nov.

Type species: Gobisaurus domoculus.

Etymology: Gobi, refers to the geographic locale.

Gobisaurus domoculus sp. nov.

Type locality: IVPP V12563 (Holotype) is believed to have been collected from the same general locality as the large theropod Chilantaisaurus maortuensis, approximately 60 km north of Chilantai (Jilantai; 39 45 N, 105 45E), on the east side of Chilantai Salt Lake (Chilantaiyen Chih), Maortu, Alashan Desert, Nei Mongol Zizhique (Inner Mongolia), China.

Formation: Ulanhushao (Suhongtu) Formation, Lower Cretaceous (Aptian–?Albian).

Etymology: domo to subjugate; and oculus, the eye

Matthew K. Vickaryous, Anthony P. Russell, Philip J. Currie, and Xi-Jin Zhao. 2001. A new ankylosaurid (Dinosauria: Ankylosauria) from the Lower Cretaceous of China, with comments on ankylosaurian relationships. Canadian Journal of Earth Sciences/Rev. can. sci. Terre 38(12):1767-1780.

http://www.bio.ucalgary.ca/contact/faculty/pdf/russell/238.pdf

https://www.researchgate.net/publication/40662046_A_new_ankylosaurid_(dinosauria__ankylosauria)_from_the_Lower_Cretaceous_of_China_with_comments_on_ankylosaurian_relationships

http://www.nhm.ac.uk/nature-online/life/dinosaurs-other-extinct-creatures/dino-directory/gobisaurus.html