Velutinids are prosobranch gastropods of the  family Velutinidae (sometimes referred to as the family Lamellariidae). They have a fully internal shell that is covered by the mantle which is often elaborately colored or ornamented. They are frequently mistaken for dorid nudibranchs. They may be distinguished by their cephalic tentacles that emerge from beneath the mantle and by the bulbous eye spots at their bases. They feed on colonial tunicates. A few of the species most frequently mistaken for sea slugs:

un. velutinid #1 CP: Maui; Aug. 2003	un. velutinid #2 CP: Maui; March, 2002	un. velutinid #3 CP: Maalaea Bay, Maui; Oct. 22, 2007
un. velutinid #4 CP: Napili Bay, Maui; Sept. 12, 1998	un. velutinid #5 CP: Kapalua Bay, Maui; April 17, 2009	Coriocella nigra CP: Kapalua Bay, Maui; May 22,  2008

For more information see:   Velutinids on the Sea Slug Forum