Tristychius
Encyclopedia
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 fin
s, probably for protection against predators.
Shark
Sharks are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago....
from the Carboniferous
Carboniferous
The Carboniferous is a geologic period and system that extends from the end of the Devonian Period, about 359.2 ± 2.5 Mya , to the beginning of the Permian Period, about 299.0 ± 0.8 Mya . The name is derived from the Latin word for coal, carbo. Carboniferous means "coal-bearing"...
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
Squaliformes
Squaliformes is an order of sharks that includes about 97 species in seven families.Members of the order have two dorsal fins, which usually possess spines, no anal fin or nictitating membrane, and five gill slits. In most other respects, however, they are quite variable in form and size...
. Tristychius also had spikes attached to the bases of its dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
s, probably for protection against predators.