Adalaria jannae

Photo by Dave Nesheim taken near Nanaimo, British Columbia, September, 1999

Adalaria jannae Millen, 1987

There is a number of small, light colored, tuberculate, bryozoan eating dorids belonging to the suctorian family Onchidoridae in the northeastern Pacific. At first glance, they all look alike and it became a real challenge to find out how many species there are and to match them with their names in the literature. Not surprisingly, a few did not match and I am still in the process of describing them. I named Adalaria jannae in part after my daughter Janna, who now has a daughter of her own. This is a small species, usually about 7 mm long but reaching a length of 15 mm. It is semi-translucent and usually cream colored but may be yellow or orange. It can be distinguished from similar species most easily by the presence of a large round, white, post-branchial tubercle whose function is unknown. The spiculose notal tubercles are small and rounded or only slightly pointed with a stout stalk. The spawn of these animals is also distinctive in that it has a sinuous appearance while similar species have much smoother coils. The radula has 28-39 rows of teeth with the formula (4-6.0.4-6). The large first lateral tooth has 13-21 small denticles.

This species feeds upon encrusting bryozoans, usually Membranipora, growing on kelp. It is found from June to January, spawning July to November. This animal has been found from British Columbia to California and is probably amphi-Pacific in distribution having been also spotted in eastern Russia ( Alexander Martynov, personal communication).

Reference: Millen, Sandra. 1987. The nudibranch genus Adalaria, with a description of a new species from the northeastern Pacific. Can. J. Zool. 65: 2696-2702.

Sandra Millen

Department of Zoology
University of British Columbia
Vancouver, B.C., Canada, V6T 1Z4
Phone (604) 822-2087; Fax (604) 822-2416
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Sandra is pictured at third from left along with Dave Nesheim (LAUPS), Alan Grant (aka the diving dentist), and Mike Miller (webmaster) taking a break between dives at Nanaimo, British Columbia during a field trip to British Columbia in September of last year. We flew up to Seattle, rented a car and continued up into Canada. We didn't see the number of branchs encountered during our '98 trip report, but nevertheless were able to get spectacular video and still footage of what we did see. And of course, diving Dodd's Narrows is always a must when in the Nanaimo area. We were very happy with our boat skipper Rod and the whole Ocean Explorers Diving operation.

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