Stathmonotus hemphillii, the blackbelly blenny, is a species of chaenopsid blenny found in coral reefs in the western central Atlantic ocean.

It can reach a maximum length of 5 centimetres (2.0 in) TL.

This species can also be found in the aquarium trade.

[2] The specific name honours the malacologist Henry Hemphill (1830-1914) who collected the type.

This Chaenopsidae article is a stub.