22 mm long. One of four found in an oyster reef matrix on a mixed mud/basalt shore inside Bahia Falsa near San Quintin.

Described by Millen and Bertsch in 2005 as D. behrensi, this species was determined to have been described 100 years earlier by Cockerell (in Cockerell & Eliot, 1905) as D. nigromaculata.