Biology:Syntomodus
Syntomodus is an extinct genus of eugeneodont from the Late Permian of Russia. The genus includes a single species, S. abbreviatus, which is known only from a single, poorly preserved set of four teeth. The species may belong to the family Edestidae.[1][2]
Discovery
The holotype specimen of Syntomodus was discovered in a Lopingian-stage deposit in the Yana River Basin of Sakha Republic, Russia. The taxon was named and described by researcher Dmitry Vladimirovich Obruchev.[1][3] The holotype (and only specimen) is part of the collection of the Palaeontological Institute in Moscow.[4]
Description
The only known specimen of Syntomodus is incomplete and has been described as poorly preserved.[1] The teeth are triangular and blade-like, and because of their state of preservation it is unclear if they are angled forwards or backwards. In life they were positioned along the midline, or symphysis, of the jaw.[1][2]
Classification
When first described by Obruchev, Syntomodus was placed in the family Helicoprionidae, within the order Bradyodonti and the subclass Holocephali.[4] Syntomodus is now presumed to instead be a member of the family Edestidae, although because the direction its teeth were angled (a characteristic which distinguishes Edestidae and Helicoprionidae) is unclear, this assignment is tentative.[1][2] In 1981 publication, researcher Rainer Zangerl proposed that Syntomodus is the most basal edestid if it is included in that family.[2]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 Ginter, Michał; Hampe, Oliver; Duffin, Christopher J. (2010). Handbook of paleoichthyology: teeth. München: F. Pfeil. pp. 132. ISBN 978-3-89937-116-1.
- ↑ 2.0 2.1 2.2 2.3 Zangerl, Rainer (1981) (in English). Chondrichthyes 1: Paleozoic Elasmobranchii (Handbook of Paleoichthyology). Friedrich Pfell (published January 1, 1981). pp. 2–3, 74–94. ISBN 978-3899370454.
- ↑ Obroucheva, Natalie V. (2014). "Dmitry Vladimirovich Obruchev: Life and destiny (1900–1970)" (in en). Paleontological Journal 48 (9): 950–963. doi:10.1134/S0031030114090093. ISSN 0031-0301. http://link.springer.com/10.1134/S0031030114090093.
- ↑ 4.0 4.1 Obruchev, Dmitry (1967) (in en). Fundamentals of paleontology. A manual for paleontologists and geologists of the USSR. 11. Jerusalem: Israel Program for Scientific Translations. pp. 353-419.
Wikidata ☰ Q135913217 entry
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