Heliobatis was a genus of stingrays that lived during the Eocene period. Fossils
of them have been found in the Green River formation of Wyoming, Colorado, and
Utah. Like modern stingrays, Heliobatis had a whip-like tail that could be used
as a defensive weapon.
The average length of Heliobatis is about 13-15 inches, though some specimans
have been found that are 3 feet long.
North America is not the only part of the world that Heliobatis inhabited.
Fossilized remains of Heliobatis have also been discovered in Asia, Australia,
Indonesia, Europe, and northern Africa.
Stingrays originated during the late part of the Cretaceous period. About 60
million years ago, they began invading the freshwater domains, i.e. lakes and
rivers. Some stingrays live in freshwater today; those are found in South
America. Most stingrays inhabit oceans.
Like their cousins, the sharks, stingrays have cartilaginous skeletons. There
are 300-350 species. Female stingrays do not lay eggs; they give live birth to
their offspring.
Many stingrays take in water through large openings (called spiracles) on the
head, rather than through the mouth. Singrays have llattened disc-shaped bodies;
the shape of the disc varies from nearly circular to diamond-shaped.

Neal Robbins

Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Order: Rajiformes
Family: Dasyatidae
Genus: Heliobatis
Type species: Heliobatis radians





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