User:Macrophyseter/sandbox2

Macrophyseter/sandbox2 Temporal range: Albian-Maastrichtian,
Squalicorax pristodontus tooth from Khouribga, Morocco
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Chondrichthyes
Subclass:	Elasmobranchii
Subdivision:	Selachimorpha
Order:	Lamniformes
Family:	†Anacoracidae
Genus:	†Squalicorax Whitley, 1939
Type species
†Corax pristodontus Agassiz, 1835
Species
List of species †S. pristodontus Agassiz, 1835 (type) †S. appendiculatus Agassiz, 1839 †S. falcatus Agassiz, 1843 †S. falcatus praecursor Sokolov, 1978 †S. kaupi Agassiz, 1843 †S. heterodon Reuss, 1845 †S. obliquus Reuss, 1845 †S. obliquus subserratus Glückman, 1980 †S. lindstromi Davis, 1890 †S. curvatus Williston, 1900 †S. bassanii Gemmellaro, 1920 †S. baharijensis Stromer, 1927 †S. primaevus Dalinkevicius, 1935 †S. kugleri Leriche, 1938 †S. yangaensis Carteville & Casier, 1943 †S. dalinkevichiusi Glückman & Shvazhaite, 1971 †S. mississippiensis Glückman, 1971 †S. volgensis Glückman, 1971 †S. obruchevi Glückman, 1980 †S. sagisicus Glückman, 1980 †S. santonicus Glückman & Zhelezko, 1980 †S. papulovi Zhelezko, 1980 †S. africanus Cappetta, 1991 †S. primigenius Landemaine, 1991 †S. coquandi Vullo et al., 2007 †S. priscoserratus Siversson et al., 2007 †S. bernardezi Guinot et al., 2013 †S. benguerirensis Cappetta et al., 2014 †S. microserratus Cappetta et al., 2014 †S. deckeri Bice & Shimada, 2016 †S. lalunaensis Guinot & Carrillo-Briceño, 2018 †S. moodyi Guinot & Carrillo-Briceño, 2018 †S. acutus Siversson et al., 2019 †S. bazzii Siversson et al., 2019 †S. mutabilis Siversson et al., 2019

Squalicorax is a genus of extinct lamniform shark known to have lived during the Cretaceous period.

Taxonomy and evolution

Carcharhiniform or lamniform?

The ambiguous characteristics of Squalicorax have led to a confusion about which shark order the genus belongs to, and to this day there remains no full certainty on the issue. Historically, scientists have suggested a placement of Squalicorax within one of four orders: the cow sharks (Hexanchiformes), the carpet sharks (Orectolobiformes), the ground sharks (Carcharhiniformes), or the mackerel sharks (Lamniformes). The first two were suggested based on the similarities of the teeth of some Squalicorax species with modern members of those orders, as well as the purported presence of skull features that are exclusive to them. The study of Squalicorax skeletons by Shimada & Cicimurri (2005) ruled out these placements by identifying a number of contradicting anatomical features.

Phylogeny

S. volgensis S. curvatus S. falcatus S. kaupi S. pristodontus

Possible phylogenetic relationships between Squalicorax species from North America based on Shimada & Cicimurri, 2006

External links

• Elasmo.com page on Squalicorax
• Cretoxyrhina mantelli - The Ginsu Shark and Squalicorax falcatus - The Crow Shark
• Squalicorax beim ReefQuest Centre for Shark Research