Xenacanthus

Xenacanthus Temporal range: Devonian–Triassic
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Chondrichthyes
Order:	Xenacanthida
Family:	Xenacanthidae
Genus:	Xenacanthus
Species
See text.

Xenacanthidae is a family of prehistoric sharks, containing the single genus Xenacanthus. The first species of the genus lived in the later Devonian, and they survived until the end of the Triassic period, 202 million years ago. These species were found in fresh water. The sharks had a long spine at the back of their head. As all fossil sharks, Xenacanthus is mainly known because of fossilised teeth and spines.

Species

• X. atriossis
• X. compressus
• X. decheni
• X. denticulatus
• X. erectus
• X. gibbosus
• X. gracilis
• X. howsei
• X. laevissimus
• X. latus
• X. luedernesis
• X. moorei
• X. ossiani
• X. ovalis
• X. parallelus
• X. parvidens
• X. robustus
• X. serratus
• X. slaughteri
• X. taylori