Xenacanthus

The foreign spike, Xenacanthus (1848)

Phylum : Chordata
Class : Chondrichthys
Subclass : Elasmobrachii
Order : Xenacanthida
Family : Xenacanthidae
Genus : Xenacanthus
Species : X. atriossis, X. compressus, X. decheni, X. denticulatus, X. erectus, X. gibbosus, X. gracilis, X. howsei, X. laevissimus, X. latus, X. luedernsis, X. moorei, X. ossiani, X. ovalis, X. parallelus, X. parvidens, X. robustus, X. serratus, X. serratus, X. slaughteri, X. taylori

  • Late Devonian/Triassic (310 - 202 Ma)
  • 80 cm long (size)
  • Oceans worldwide (map)

Xenacanthus is a genus of prehistoric sharks. The first species of the genus lived in the later Devonian period, and they survived until the end of the Triassic, 202 million years ago. Fossils of various species have been found worldwide.

Xenacanthus had a number of features that distinguished it from modern sharks. This freshwater shark was about one meter (three feet) in length. The dorsal fin was ribbon-like and ran the entire length of the back and round the tail, where it joined with the anal fin. This arrangement resembles that of modern conger eels, and Xenacanthus probably swam in a similar manner. A distinctive spine projected from the back of the head, and gives the genus its name. The teeth had an unusual V-shape, and it probably fed on small crustaceans, and heavily scaled palaeoniscid fishes.

As in all fossil sharks, Xenacanthus is mainly known because of fossilised teeth and spines.

Saturday’s shark for SharkWeekSketchJam: the ancient Xenacantus!

Xenacanthus is a genus of prehistoric sharks. The first species of the genus lived in the later Devonian period, and they survived until the end of the Triassic, 202 million years ago. Fossils of various species have been found worldwide.

Xenacanthus had a number of features that distinguished it from modern sharks. This freshwater shark was about one meter (three feet) in length. The dorsal fin was ribbonlike and ran the entire length of the back and round the tail, where it joined with the anal fin. This arrangement resembles that of modern conger eels, and Xenacanthus probably swam in a similar manner. A distinctive spine projected from the back of the head and gave the genus its name. The teeth had an unusual “V” shape, and it probably fed on small crustaceans and heavily scaled palaeoniscid fishes.

As with all fossil sharks, Xenacanthus is mainly known because of fossilised teeth and spines.

Such an old shark…

22/01/2016
Xenacanthus
When: All the way through the Devonian period to the end of the Triassic
Where: Global
Size: up to bout 1 metre
Fun fact:The spine on its head was made out of bone unlike the rest of its cartilaginous skeleton