Reprinted from PCAS, ser. 4, vol. 57 (April 2006) PROCEEDINGS OF THE CALIFORNIA ACADEMY OF SCIENCES Fourth Series Volume 57, No. 8, pp. 357–364, 3 figs. April 18, 2006 A New Species of Adalaria (Nudibranchia: Onchidorididae) from the Northeastern Pacific Sandra V. Millen Department of Zoology, University of British Columbia, 6270 University Boulevard, Vancouver, B.C., Canada, V6T 1Z4. Email:
[email protected] A new species of Adalaria Bergh, 1878 is described from the northeastern Pacific. It is white, characterized by highly spiculose, rounded tubercles with narrow bases, 4- 6 tubercles on the rhinophore sheath, and separate gill leaves inserted in a circlet. This species is known to range from Alaska to Oregon. A comparison is made between this new species and others in the genus. KEY WORDS: Adalaria, Arctadalaria, Onchidorididae, phanerobranch, Nudibranchia, Northeastern Pacific The genus Adalaria, in the family Onchidorididae, is composed of small white, off-white, or yellow phanerobranch dorid nudibranchs with a spiculose dorsum and tubercles, an ample mantle margin, lamellate rhinophores and a veil-like head. They are bryozoan feeders and are similar to another bryozoan feeding genus, Onchidoris, which are usually white or brown in colour. Both gen- era have a reduced or absent, rectangular central tooth, a large, flat, beak-like first lateral tooth, which may have a few inner denticles, and small, oval, outer lateral teeth with a small hook. Adalaria are distinguished by having more than one outer lateral tooth and by usually having a smooth rather than a papillate lip disk, although A. jannae Millen, 1987 has a papillate lip disk.