Shells are highly variable in sculpture and colouration, but shells are often dark with a white aperture.

Penion sulcatus is endemic to New Zealand. The species is found of the entire North Island and northern South Island coasts. Penion sulcatus is a carnivore and is known to feed on mussels and Dosina zelandica zelandica.

Shells found in middens of historic Māori settlements indicate that P. sulcatus may have been intentionally foraged as a food-source.