Pterosphenus is an extinct genus of marine
snake of the
Eocene period.[1][2]
Classification
Pterosphenus belong to the
Alethinophidia snakes, a clade which includes all snakes outside of
blind and
thread snakes, and more specifically to the extinct
Palaeophiidae. Its closest relative is Palaeophis, of which both belong to the subfamily
Palaeophiinae. Five species are known, P. schucherti from North America, P. sheppardi from South America, P. schweinfurthi from northern Africa and P. biswasi, and P. kutchensis from Asia.
Description
While only known from partial remains, enough has been found of Pterosphenus to suggest it was a large reptile. Based on the regression model used to estimate the length of
boids, the most reliable length estimate lies between 2.5 and 4.8 metres (8.2 and 15.7 ft); the largest vertebra may have belonged to an individual reaching 5.7 metres (19 ft) in length.[3] Its body was strongly laterally compressed as an adaptation to pelagic life.
Palaeoenvironment and Palaeoecology
A marine ocean dweller, Pterosphenus lived in the shallow seas of the future eastern US (fossils are known from
Texas,
Louisiana,
Mississippi, and
Arkansas and up north to
New Jersey), Africa in the
Tethys Ocean (fossils are known from
Morocco,[4]Libya,[5]Nigeria,[6] and
Egypt[7]), South America (fossils are known from
Ecuador[8]) and southern Asia (fossils are known from
India[9]). Pterosphenus was a top predator of the ecosystem, likely preying on fish and molluscs found in the same area.
It is certain that Pterosphenus would have encountered basal
cetaceans of the time like Zygorhiza, Dorudon, and Basilosaurus, though its likely a mixed of
niche partitioning and living in different areas in the case of Basilosaurus (which lived in estuary ecosystems according to recent finds) would prevent competition between the species.
References
^Case, Dennis; Parmley, Gerard (September 23, 1988). "New records of Eocene sea snakes (Pterosphenus) from Louisiana". Journal of Vertebrate Paleontology. 8: 334–339.
JSTOR4523211.
^Westgate, Jim F.; Ward, James. W. (1981). "The giant aquatic snake Pterosphenus schucherti (Palaeophidae) in Arkansas and Mississippi". Journal of Vertebrate Paleontology. 1 (2): 161–164.
doi:
10.1080/02724634.1981.10011887.