Galeodea triganceae is a species of large sea snail, a marine gastropod mollusc in the family Cassidae, the helmet snails.

The maximum shell height is 48 mm, and maximum width 31 mm.

This species is endemic to New Zealand[1] including the Chatham Islands.

This helmet shell is found at depths of between 90 and 600 m.

This Cassidae-related article is a stub.