Reptilia - Dinosauria

Alternative combination: Sauroidichnites tenuissimus

Synonym: Harpedactylus gracilis Hitchcock 1848

Belongs to Harpedactylus according to R. S. Lull 1904

Sister taxa: Harpedactylus crassus, Harpedactylus gracilior

Type specimens:

• Harpedactylus tenuissimus: AC 27/8, a footprint. Its type locality is Wethersfield tracksite, which is in a Hettangian/Sinemurian fluvial-lacustrine shale/sandstone in the Portland Formation of Connecticut.
• Harpedactylus gracilis: Its type locality is below Turners Falls, tracksite, which is in a Hettangian/Sinemurian fluvial-lacustrine sandstone/shale in the Portland Formation of Massachusetts.

Ecology: