This is without question my favorite Indo-Pacific Cuthona. A large species for this genus, it usually reaches 20 mm in length but in this instance was recorded at a whopping 45 mm - big enough for most of us to find on subtidal sojourns!
The head is white and the cephala-tentacles and rhinophores orangish-brown. The are 18-20 rows of cerata, the tallest along each ridge being nearest the dorsal midline. The 'Cub Scout' blue and yellow ceratal colors vary, but go something like this. They are tipped by either white or black. If white, there is a thin subapical black band. Below this is a yellow band followed by a terrific blue band (appearing grey in Mike's specimen shown here). See Debelius, pg 306, Nudibranchs and Sea Snails. Indo-Pacific Field Guide for the typical blue ceratal banding. The remaining 1/2- 2/3's of the ceras being white. As shown clearly here in Mike's photo, the amount of white on the cerata varies from the mid-line outwards, the outermost cerata having little or no white at all.
A hydroid predator, its distribution ranges from South Africa and Tanzania to Western Australia and Indonesia.
The next time you see this tidy Cub Scout of a nudibranch scouting the bottom to do a good deed, please salute it for me.
Webmaster's Note Aug. 9th, 2002 : Updated information that has appeared on Bill Rudman's Sea Slug Forum since our presentation of Cuthona Kanga indicate this animal is probably Cuthona yamasui . What can be said, they sure look the same to me!
We found El Doroado to be a well managed diving resort with an outstanding house reef right in front. Perhaps a little bit pricey from what we are accustomed to in the Philippines, but nevertheless well worth visiting if you are in the area!
David W. Behrens
Pacific Coast Nudibranchs
Send Dave mail at firstname.lastname@example.org