Ischnacanthus gracilis

Ischnacanthus was a type of fish belonging to the class Acanthodii. Remains have been discovered in the Lochkovian/Emsian stages of the Devonian Period in the Tillywhandland quarry (one of the best early Devonian fish sites in Scotland), Old Red Sandstone, Forfarshire, they first appeared in the very late Silurian Period. Fossil remains have also been discovered in North America.

Their bodies were covered with small mosaic scales, they had small teeth which were primarily situated in the lower jaws, and some of the species had no teeth. The majority of their fins (except caudal) were supported by elongated spines made of dentine. Three species are attributed to Ischnacanthus; the more commonly known I.gracilis and, I.kingi and I.wickhami, the latter two named by White in 1961, they were most likely active predatory fish.

Name

Ischnacanthus gracilis

Authority

Egerton, 1861

Meaning of generic name

Thin spine

Meaning of specific name

graceful

Size

Length: 10 cm

Remains

Complete fossils.

[Complete skeletons or more ?]

Age and Distribution

Early Permian, Tillywhandland Quarry, Forfar, Scotland

Classification

Acanthodii Ischnacanthiformes Ischnacanthidae

Further Reading

C. J. Burrow. 2007. Early Devonia (Emsian) Acanthodian Faunas Of The Western USA. Journal of Paleontology; September 2007; v. 81; no. 5; p. 824-840.