Mammalia - Sirenia - Dugongidae

Synonyms: Hydrodamalis spissa Furusawa 1988, Hydrodamalis spissus Furusawa 1988

Full reference: D. P. Domning. 1978. Sirenian evolution in the North Pacific Ocean. University of California Publications in Geological Sciences 118:1-176

Belongs to Hydrodamalis according to D. P. Domning 2008

Sister taxon: Hydrodamalis gigas

Type specimens:

• Hydrodamalis cuestae: UCMP 86433. Its type locality is Avilla Beach W, which is in a Piacenzian marine sandstone in the Pismo Formation of California.
• Hydrodamalis spissa: TMANH 0001, a partial skeleton (partial skull & skeleton).

Ecology: aquatic herbivore