Known from nth Atlantic and Arctic Oceans [Svalbard (Spitzbergen), Greenland, nthn Norway] and Atlantic coast of Nth America [Cape Cod to Nova Scotia] (Robilliard, 1970).
Locality: Svalbard (Spitzbergen), 15 metres, Norway, Arctic Ocean, 2002, Very silty bottom out of a glacier. Length: 15 cm. Photographer: Erling Svensen.
Body translucent with fine reddish brown specks giving the body a reddish tinge and a pattern of reticulate reddish wrinkles. Scattered over dorsum are quite large white spots. Verrill described the white spots as yellow and also describe yellow tips to the gills and oral veil papillae. In the specimen illustrated here the spots and tips are white not yellow.
The body is relatively flattened and short and the large oral veil has four or five papillae on each side. They are usually thick and short with small simple branches. There are 6 - 7 pairs of gills down each side of the body. They are short and relatively unbranched. Often, each 'gill' consists of two or three separate trunks inserting separately into the body wall.
Little is known of the ecology of this species. Robilliard (1972) notes reports of it living from the intertidal to 230 m deep. He also reports frinding hydroid remains in the stomachs of Nth American animals and sabellid worms in animals from Norway.
Erling Svensen's animals at 15 cm long, are much longer than any previous record of the species.
Bergh, L. S. R. (1894) Reports on the dredging operations off the west coast of Central America to the Galapagos, to the west coast of Mexico, and in the Gulf of California, in charge of Alexander Agassiz, carried on by the U. S. Fish Commission steamer "Albatross", during 1891, Lieut. Commander Z. L. Tanner, U.S.N. commanding. Part 13. Die Opisthobranchien. Bulletin of the Museum of Comparative Zoology, Harvard, 32: 125-233, Pls.1-12.
Robilliard, G. A. (1970) The systematics and some aspects of the ecology of the genus Dendronotus. The Veliger, 12: 433-479, pls. 63-64.
Robilliard, G. A. (1972) A new species of Dendronotus from the northeastern Pacific with notes on Dendronotus nanus and Dendronotus robustus (Mollusca: Opisthobranchia). Canadian Journal of Zoology, 50(4): 421-432.
Verrill, A.E. (1870) Contributions to zoology from the Museum of Yale College. No 8 - Descriptions of some New England Nudibranchiata. American Journal of Science & Arts, 50: 405-406.
Rudman, W.B., 2007 (March 6) Dendronotus robustus Verrill, 1870. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/dendrobu
Dendronotus robustus from Massachusetts, USA
From: Alan Shepard, March 8, 2007
Dendronotus robustus from Spitzbergen, Nth Atlantic
From: Erling Svensen, March 7, 2007