Thuridilla carlsoni

Photographed by Webmaster at Tulamben, Bali, Indonesia
Oct. 2001

Thuridilla carlsoni, Gosliner 1995

This BOW is dedicated to the pioneering nudibranch couple, Clay Carlson and Patty Jo Hoff who first discovered this species. Clay and Patty Jo are mostly into bubble shells now but it is absolutely amazing the small branchs Clay will bring in as a result of his search for the elusive bubble shells.

Thuridilla carlsoni is of course in the Sacoglossa order! Again one has to ask the question as in BOW #279 and that is how are they able to crawl out in the open away from the usual algal prey most Saco's seem to associate themselves with. Cimino and Ghiselin postulate that color adaptation has enabled Thuridilla to move from a more traditional cryptic setting of larger algal masses to smaller patches protected by defensive chemicals derived from their food. It has been my experience in the Indo-Pacific to see Thuridilla roaming about much in the manner of some highly decorated chromadorids.

According to Gosliner, T. carlsoni is most closely related to Thuridilla multimarginata although they differ in certain external color aspects. Quite often the inside of the parapodia of T. carlsoni can be quite striking as already seen in Thuridilla splendens and is also true of T. carlsoni .

T. carlsoni has previously been featured on Bob Bolland's Okinawa Slug Site and also Bill Rudman's SeaSlug Forum . Distribution is probably throughout the Indo-Pacific.

Mike Miller
San Diego, CA
Dec. 2001


Camino, G. and Ghiselin, M. (1998) Chemical defense and evolution in the Sacogolossa (Mollusca: Gastropoda: Opisthobranchia. Chemoecology, 8:51-60

Gosliner, T.M. (1995) The genus Thuridilla (Opisthobranchia: Elysiidae) from the tropical Indo-Pacific, with a revision of their phylogeny and systematics of the Elysiidae. Proceedings of the California Academy of Sciences, 49(1): 1-54.

Clay and Patty Jo at home in their "nudibranch" laboratory at Merizo, Guam. For those who have dove with Clay, you will know his passion is bubble shells. How he finds them is beyond this Webmaster. Judging from the camera equipped microscope as the backdrop, one has a better idea how Clay and Patty Jo are able to capture the unique morphology of bubble shells.

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