Ptomacanthus
Extinct genus of cartilaginous fishes
From Wikipedia, the free encyclopedia
Ptomacanthus (meaning thorny corpse) is an extinct genus of spiny shark,[1] an early relative of living cartilaginous fishes (sharks, rays, and chimaeras).[2]
| Ptomacanthus Temporal range: | |
|---|---|
| |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Chondrichthyes |
| Genus: | †Ptomacanthus Miles 1973[1] |
| Species: | †P. anglicus |
| Binomial name | |
| †Ptomacanthus anglicus Miles 1973[1] | |
Location found
Ptomacanthus is known mainly from the Old Red Sandstone of the United Kingdom.[1] The most completely known species, P. anglicus is known from several articulated fossils from Wayne Herbert Quarry, Herefordshire, United Kingdom.[1] Two indeterminate species are known from shoulder-girdles recovered from Castle Mattock Quarry, Herefordshire and Zaleszychi, Ukraine.[1]
Description
Paleobiology
P. anglicus is important to our understanding of early vertebrate evolution as it preserves part of the braincase, a scientifically informative part of the skeleton.[2] Because of the cartilaginous makeup of the acanthodian internal skeleton, it is very rarely preserved, and the braincase of Ptomacanthus is only the second acanthodian braincase known to science (the first being that of Acanthodes).[4] The description of this braincase reignited debate over the relationships of acanthodians as well as those of early vertebrates more generally.[2][4]
