Syntomodus
Extinct genus of cartilaginous fish
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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]
| Syntomodus Temporal range: Permian | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Chondrichthyes |
| Order: | †Eugeneodontiformes |
| Family: | †Edestidae |
| Genus: | †Syntomodus |
| Species: | †S. abbreviatus |
| Binomial name | |
| †Syntomodus abbreviatus Obruchev, 1964 | |
| Synonyms | |
|
Syntomotus abbreviatus Ginter et al. 2010 | |
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]