Doriopsis granulosa
Pease, 1860

Order: NUDIBRANCHIA
Suborder: DORIDINA
Family: Dorididae

DISTRIBUTION

Indo-West Pacific

PHOTO

Upper: Pointe de Babouillat, near Koumac, New Caledonia, Intertidal, coral rubble reef, shallow lagoon 13 October 1993, 7mm long alive, on orange sponge, AM C200465.
Lower: Arrawarra Headland, Coffs Harbour, New South Wales, Australia. upper intertidal under rocks on yellow-orange sponge, 16 March 1988. AM C155788. Length 28mm. [left photo showing gills] Photos: Bill Rudman

Species of Doriopsis are characterised by the arrangement of the gills in a transverse line across the back rather than in the typical dorid circle. There is a dorsal flap covering the gill opening. Doriopsis granulosa has low rounded tubercles over the mantle. It ranges in colour from a pale yellow-orange to a dark green. In yellow-green specimens the tubercles have scattered brown specks, especially on the sides, while in dark green animals the tubercles are often completely brown. Often found feeding on a yellow or orange sponge, which is probably Prianos phlox.

Specimens of Doriopsis are either deep blue, green or yellow and there has been considerable confusion in the literature concerning how many species there are in the genus. At one extreme 4 species, one each of green and blue and two of yellow have been suggested, while at the other extreme only one variably coloured species has been proposed.

Biological observations from throughout the Pacific suggest that there are at least two species, one yellow or green and one deep blue. It is also possible that the yellow New Zealand species, Doriopsis flabellifera (Cheeseman, 1881), is a third valid species. The earliest name for the yellow/green species is D. granulosa and for the blue, D. pecten. Reports from Hawaii (Kay & Young, 1969; Bertsch & Johnson,1981), Japan (Hamatani, 1961, Baba & Hamatani, 1961), and the central Pacific (Young, 1967; Johnson, 1981) show that D. pecten feeds exclusively on a deep blue sponge Terpios, and D. granulosa on a yellow or orange sponge, identified by Young (1967) as Prianos phlox de Laubenfels, 1954. The eggs of D. granulosa are reported to be yellow, while those of D. pecten are cream, and the egg ribbon of D. granulosa is about four times as wide as that of D. pecten. The green 'species' or 'form' has often been named Doriopsis viridis Pease, 1861.

Reference:
• Baba, K. & Hamatani, I., 1961. On two new species of Doriopsis (syn. Ctenodoris) from Japan (Nudibranchia - Dorididae). Publications of the Seto Marine Biological Laboratory, 9: 63-65.
• Bertsch, H. & Johnson, S., 1981. Hawaiian Nudibranchs. Honolulu: Oriental Publishing Co.
• Hamatani, I., 1961. Notes on veligers of Japanese opisthobranchs (4). Publications of the Seto Marine Biological Laboratory, 9(2): 353-361.
• Johnson, S., 1981. Blue camouflage in a nudibranch. Hawaiian Shell News, 29(6): 14.
• Kay, E.A. & Young, D.K., 1969. The Doridacea (Opisthobranchia: Mollusca) of the Hawaiian Islands. Pacific Science, 23: 172-231.
• Pease, W.H. (1860). Descriptions of new species of mollusca from the Sandwich Islands. Proceedings of the Zoological Society of London, 28: 18-37.
• Young, D.K., 1967. New records of Nudibranchia from the Central and West-Central Pacific with a description of a new species. The Veliger, 10: 159-173

Authorship details
Rudman, W.B., 2003 (March 7) Doriopsis granulosa Pease, 1860. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/dorigran

Copyright © Australian Museum, 1998-2010