A new species of Doriopsilla (Nudibranchia: Dendrodorididae) from the Pacific coast of North America, including a comparison with Doriopsilla albopunctata (Cooper, 1863)

Much confusion has surrounded the systematics of the yellow species of Dendrodorididae inhabiting the Pacific coast of North America. Re-examination of Doris albopunctata Cooper, 1863, indicates that it is properly placed in Doriopsilla. Examination of specimens from different localities throughout California, the Pacific coast of Baja California, and within the Gulf of California, indicates that ail white-gilled specimens are conspecific with D. albopunctata, and that D. fulva (MacFarland, 1905) and D. reticulata (Cockerell & Eliot, 1905) are regarded as junior synonyms. A second species with yellow gills is here described as Doriopsilla gemela, It differs from D. albopunctata in aspects of its color pattern, external morphology, digestive system, reproductive anatomy, and developmental biology. The two species also differ in allozyme allelic frequencies. Doriopsilla gemela and D. albopunctata are also compared to other members of the genus present in the eastern Pacific. These comparisons show that, while D. gemela and D. albopunctata are externally similar to each other, their internal anatomy is more similar to other species than to each other.