Eusthenopteron

***Eusthenopteron*** is an extinct genus of lobe-finned fish from the Late Devonian. Early depictions of _Eusthenopteron_ show it emerging onto land; however, everyone now agrees that it is a strictly aquatic animal. Notably, it is one of the earliest sarcopterygians in which the humerus is preserved. Among the various species of this genus, the most popular is undoubtedly _E. foordi_. Also, it’s the earliest fish with preserved bone marrow.

The species:

- _Eusthenopteron foordi_ (type species)
- _Eusthenopteron farloviensis_
- _Eusthenopteron jenkinsi_
- _Eusthenopteron kurshi_
- _Eusthenopteron obruchevi_
- _Eusthenopteron savesoderberghi_
- _Eusthenopteron traquairi_
- _Eusthenopteron wenjukowi_

## Description

_Eusthenopteron_ is a medium-to large-sized tristichopterid. _E. foordi_ is estimated to exceed 1.5 m (4 ft 11 in), while _E. jenkinsi_ probably reached 2.1 m (6 ft 11 in). The earliest-known fossilized evidence of bone marrow has been found in _Eusthenopteron_, which may be the origin of bone marrow in tetrapods.

The most notable features of _Eusthenopteron_ are the pectoral and pelvic fins. It had a large head with powerful jaws that could've been capable of biting prey. However, unlike the early tetrapods though, _Eusthenopteron_ did not have larval gills.

## Distribution

Finds have been made in Europe and North America.

## Some species

_Eusthenopteron foordi_ is a well-known species. The other species, however, are not well-known.

### _Eusthenopteron foordi_

_Eusthenopteron foordi_ is the type species of _Eusthenopteron_. It is the most famous and well-known species of _Eusthenopterus_. It is also one of the most scientifically important fossil vertebrates.

### _Eusthenopteron farloviensis_

_Eusthenopteron farloviensis_ is another species of _Eusthenopteron_. Like the other species except _E. foordi_, it is not well-known.

### _Eusthenopteron jenkinsi_

_Eusthenopteron jenkinsi_ is yet another species of _Eusthenopteron_. Little is known about this species. However, it may have been up to six feet long with a torpedo-shaped body and fangs. It was probably a large species for the _Eusthenopteron_.

## Paleoecology

_Eusthenopteron_ probably hunted other fish by setting ambushes on the seabed, where it rested with its robust fins. Although fleshy and particularly strong, it is in fact unlikely that they could take the animal out of the water.

## What it ate

_Eusthenopteron_ preyed on smaller fish. Its teeth were small yet sharp, and were used to nab prey as the lobe-finned fish swallowed them whole.

## Out of water

_Eusthenopteron_ was depicted hauling itself out of a pond, much like a mudskipper. However, no scientific evidence supports this.

## Related pages

- Hyneria
- Rhizodus
- Pleuropholis
- Eusthenodon
- Cabonnichthys
- Archaeolepidotus
- List of prehistoric bony fish genera

## References

1. <small>Downs, Jason P.; Daeschler, Edward B.; Long, Alison M.; Shubin, Neil H. (2018). "_Eusthenopteron jenkinsi_ sp. nov. (Sarcopterygii, Tristichopteridae) from the Upper Devonian of Nunavut, Canada, and a Review of _Eusthenopteron_ Taxonomy". _Breviora_.</small>
1. <small>Zylberberg, L., Meunier, F. J. and Laurin, M. 2010. A microanatomical and histological study of the postcranial dermal skeleton in the Devonian sarcopterygian _Eusthenopteron foordi. Acta Palaeontologica Polonica_ 55: 459–470.</small>
1. <small>Schultze, H.-P. 1984. Juvenile specimens of _Eusthenopteron foordi_ Whiteaves, 1881 (Osteolepiform rhipidistian, Pisces) from the Late Devonian of Miguasha, Quebec, Canada. _Journal of Vertebrate Paleontology_. **4**: 1-16.</small>

## Other websites

- Palaeos.com – Vertebrates – Sarcopterygii (archive)