| Tristychius Temporal range: Early Carboniferous |
|
|---|---|
| Restoration | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Chondrichthyes |
| Subclass: | Elasmobranchii |
| Order: | Ctenacanthida |
| Genus: | Tristyichius |
Tristychius is an extinct genus of shark from the Carboniferous period. Fossils have been found in Scotland.
Tristychius was a small shark, about 60 centimetres (2 ft) long. It had a well-developed upturned caudal fin, similar to that of many modern sharks. Physically it may have resembled a modern dogfish. Tristychius also had spikes attached to the bases of its dorsal fins, probably for protection against predators.[1]