Habrosaurus

Habrosaurus Temporal range:
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Amphibia
Order:	Urodela
Family:	Sirenidae
Genus:	†Habrosaurus Gilmore, 1933
Synonyms
Adelphesiren

For the duck-billed dinosaur, see Hadrosaurus

Habrosaurus is an extinct genus of prehistoric salamanders, and the oldest known member of the family Sirenidae. Two species are known, H. prodilatus from the middle Campanian Dinosaur Park Formation of Alberta, and H. dilatus from the late Maastrichtian and Paleocene of western North America. It is relatively common in the Lance Formation of Wyoming, and less common in the Hell Creek of Montana.

Description

Habrosaurus was one of the largest lissamphibians of all time, comparable to modern giant salamanders at about 1.6 meters. H. prodilatus possessed chisel-like teeth, while H. dilatus had bulkier crowns. The teeth of H. dilatus also exhibited heavy wear facets while those of H. prodilatus had only mild wear, suggesting that H. dilatus was more adapted for durophagy than H. prodilatus. H. dilatus may have preyed upon arthropods with hard carapaces as well as mollusks.

Classification

Habrosaurus is a sister taxa to both Pseudobranchus and Siren.