Protocentrophorus is a genus of was a genus of dogfish shark that existed during the Cretaceous.[2] Fossils have been found in the Tauragė County of Lithuania and British Columbia in Canada.[3] Known from teeth, they were originally assigned to the genus Centrophorus.

Protocentrophorus
Temporal range: 99–72 Ma Cenomanian to Campanian
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Order: Squaliformes
Family: Squalidae
Genus: Protocentrophorus
Adnet et al. 2008
Type species
Centrophorus balticus
Dalinkevičius, 1935
Other species
  • Protocentrophorus steviae Cappetta et al. 2019[1]

While some classify Protocentrophorus as belonging to the family Squalidae, phylogenetic tests indicate that it might be a member of the Centrophoridae.[4]

Description

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This squaloid shark had small teeth that combined traits from two modern shark families, Squalidae and Centrophoridae. The lower teeth were flattened from front to back, as seen in Centrophoridae, and wider than they were tall, like those in Squalidae. The base of the tooth root was flat, long, and almost vertical, similar to Centrophoridae, but it lacked the special hollow for overlapping teeth and the prominent root face typical of Squalidae. The apron, a part of the tooth, was moderately high and didn't extend past the base of the root, while the uvula, a small part of the tooth, was reduced and not prominent. Additionally, there was no infundibulum, a funnel-like structure, present.[2]

References

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  1. ^ Cappetta, Henri; Morrison, Kurt; Adnet, Sylvain (2021-08-03). "A shark fauna from the Campanian of Hornby Island, British Columbia, Canada: an insight into the diversity of Cretaceous deep-water assemblages". Historical Biology. 33 (8): 1121–1182. Bibcode:2021HBio...33.1121C. doi:10.1080/08912963.2019.1681421. ISSN 0891-2963.
  2. ^ a b Adnet, Sylvain; Cappetta, Henri; Mertiniene, Romualda (2008-08-01). "Re-evaluation of squaloid shark records from the Albian and Cenomanian of Lithuania". Cretaceous Research. 29 (4): 711–722. Bibcode:2008CrRes..29..711A. doi:10.1016/j.cretres.2008.01.014. ISSN 0195-6671.
  3. ^ "†Acanthidium Lowe 1839 (dogfish shark)". PBDB.org.
  4. ^ Feichtinger, I.; Guinot, G.; Straube, N.; Harzhauser, M.; Auer, G.; Ćorić, S.; Kranner, M.; Schellhorn, S.; Ladwig, J.; Thies, D.; Pollerspöck, J. (December 2022). "Revision of the Cretaceous shark Protoxynotus (Chondrichthyes, Squaliformes) and early evolution of somniosid sharks". Cretaceous Research. 140: 105331. Bibcode:2022CrRes.14005331F. doi:10.1016/j.cretres.2022.105331. hdl:11250/3061165. ISSN 0195-6671.