Tristichopteridae

Tristichopteridae Temporal range: 392–359Ma PreЄ Є O S D C P T J K Pg N Middle - Late Devonian
Teeth of Platycephalichthys, in CosmoCaixa Barcelona
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Sarcopterygii
Clade:	Eotetrapodiformes
Family:	†Tristichopteridae Cope, 1889
Genera
See below

Tristichopterids (Tristichopteridae), were a diverse and successful group of tetrapodomorph fishes living throughout the Middle and Late Devonian. They first appeared in the Givetian stage of the Middle Devonian. Within the group sizes ranged from a few tens of centimeters (Tristichopterus) to several meters (Hyneria and Eusthenodon).

Some tristichopterids share some of the features of the elpistostegalians, a paraphyletic assemblage of fishes close to the origin of tetrapods. This mainly concerns the shape of the skull and a reduction in size of the posterior fins.

An old and persistent notion is that Eusthenopteron was able to crawl onto land using its fins. However, there is no evidence actually supporting this idea. All tristichopterids went extinct by the end of Late Devonian.

Genera of Tristichopterids

• Cabonnichthys
• Canningius
• Eusthenodon
• Eusthenopteron
• Hyneria
• Jarvikina
• Langlieria
• Mandageria
• Notorhizodon
• Platycephalichthys
• Tristichopterus
• Heddleichthys

Phylogeny

Below is a cladogram from Swartz, 2012:

Tetrapodomorpha	Kenichthys Rhizodontidae Canowindridae Megalichthyiformes Eotetrapodiformes Tristichopteridae Spodichthys Tristichopterus Eusthenopteron Jarvikina Cabonnichthys Mandageria Eusthenodon Tinirau Platycephalichthys Elpistostegalia Panderichthys Tiktaalik Elpistostege Tetrapoda

References

• Ahlberg, PE and Z Johanson (2001). "Second tristichopterid (Sarcopterygii, Osteolepiformes) from the Upper Devonian of Canowindra, New South Wales, Australia, and phylogeny of the Tristichopteridae." in Journal of Vertebrate Palaeontology 17:563-673.
• Johanson, Z. and P.E. Ahlberg (1997). "New tristichopterid (Osteolepiformes; Sarcopterygii) from the Mandagery Sandstone (Famennian) near Canowindra, N.S.W., Australia." in Transactions of the Royal Society of Edinburgh 88:39-53.