Clepsysaurus

Clepsysaurus is a dubious genus of extinct archosaur from the Carnian Passaic Formation and Lockatong Formation of Lehigh [County, Pennsylvania|Lehigh County], and York County, Pennsylvania.
Two species are known: C. pennsylvanicus and C. veatleianus.

Discovery and naming

''Clepsysaurus pennsylvanicus''

The holotype of C. pennsylvanicus, ANSP 9526, 9555-71, 9594-5, consists of teeth, ribs and vertebrae from the Passaic Formation of Pennsylvania. It was described by Isaac Lea in 1851.
Other specimens of C. pennsylvanicus are known, including ANSP 15071, AMNH 2337 and ANSP 15529.
A left anterior dentary and right dentary, from the Lockatong Formation, found on the farm of George Huber was identified by Colbert as belonging to C. pennsylvanicus.

''Clepsysaurus veatleianus''

The holotype of C. veatleianus, AMNH 2331, consists of a single broken tooth, with AMNH 2330, a tooth, as a referred specimen—these were found in the Phoenixville tunnel in York County, Pennsylvania. C. veatleianus was described by Edward [Drinker Cope] in 1876.

Classification

Clepsysaurus was traditionally classed as a sauropodomorph, but more recent studies indicate that it was either a dubious basal archosaur or a member of the Phytosauria. Clepsysaurus was eventually seen as a synonym of either the dubious archosaur Palaeosaurus or the sauropodomorph Anchisaurus, but Clepsysaurus was eventually resurrected as a valid, but dubious, genus.