How to Distinguish from Similar Species: The sea lemon Anisodoris nobilis has spots only between the tubercles, and the rhinophores and gills are lighter than the rest of the dorsum. This species does not smell and produces little mucus, while Anisodoris nobilis may give off lots of sweet-smelling mucus when disturbed. This species' congener, Archidoris odhneri, does not have the dark spots on the dorsum
Geographical Range: Kachemak Bay, Alaska to San Diego, CA
Depth Range: Intertidal to 50 m. Common intertidally in north end of range, subtidal at south end.
Habitat: Rocky areas and pilings, open coast and protected waters.
Biology/Natural History: Feeds on yellow crumb-of-bread sponge Halichondria panicea, as well as other sponges. Animals are simultaneous hermaphrodites, lay eggs throughout the year. Non-motile sperm from partner is stored in a seminal receptacle for some time before the sperm become motile and fertilize the eggs as they are laid. Eggs are in capsules of several eggs each, which are then formed into a narrow cord which is folded into a bright yellow or cream gelatinous ribbon of about 2 million eggs. The ribbon is attached in a coil by one edge to a hard substrate. Egg masses exposed to the light have higher mortality rates. Eggs hatch in 20-25 days, trochophore larvae settle within about 2 hours of hatching.
Sponges which live on the motile scallop Chlamys hastata are less vulnerable to predation by this nudibranch.
According to Baltzley et al., (2011), many gastropods, including this species, have a special network of pedal ganglia in their foot which assists in crawling. The two main neurons involved produce pedal peptides which elicit an increase in the rate of beating of cilia on the foot, resulting in crawling.
Kozloff 1987, 1996
Smith and Carlton, 1975
Baltzley, Michael J., Allison Serman, Shaun D. Cain, and Kenneth J. Lohmann, 2011. Conservation of a Tritonia pedal peptides network in gastropods. Invertebrate Biology 130: 4 pp. 313-324
Bloom, S., 1975. The motile escape response of a sessile prey: a sponge-scallop mutualism. J. Exp. Mar. Biol. Ecol. 17: 311-321
General Notes and Observations: Locations, abundances, unusual behaviors:
These nudibranchs are quite common around Rosario, and also on the open coast of Washington.
Authors and Editors of Page:
Dave Cowles (2005): Created original page