Hallaxa cryptica
Gosliner & Johnson, 1994
Order: NUDIBRANCHIA
Suborder: DORIDINA
Superfamily: EUDORIDOIDEA
Family: Actinocyclidae
DISTRIBUTION
Known from Marshall Ids, Philippines, and here from Kerama Is., southern Japan.
PHOTO
Under side of small dead coral, Kerama Is. near Okinawa,Japan. Approx 15mm long, depth 3m. PHOTO: Atsushi Ono.
Grows to about 25mm long. General body varies in colour from translucent cream to light purple brown. Both colour forms have opaque white spots which appear to be tubercles but are not. Gills and rhinophores similar colour to the mantle. Cryptic on its food sponge.
Reference:
• Gosliner, T.M. & Johnson, S. (1994) Review of the genus Hallaxa (Nudibranchia: Actinocyclidae) with descriptions of nine new species. The Veliger, 37(2): 155-191.
Rudman, W.B., 2000 (April 5) Hallaxa cryptica Gosliner & Johnson, 1994. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/hallcryp
Related messages
Hallaxa cryptica from Kerama Id, Japan
April 6, 2000
From: Atsushi Ono
Dear Bill,
Thank you for your comments about Goniodoris glabra.
This time I have attached a milky, translucent dorid. This animal is so hard to take a photo clearly, that my photos look like out of focus. I think this is Hallaxa species.... Is this Hallaxa cryptica?
It is about 15mm long, found at 3m depth, under side of small dead coral, at Kerama Is. near Okinawa in Japan.
Could you help me to identify this?
Sincerely,
Atsushi Ono
ononini@cosmos.ne.jp
Ono, A., 2000 (Apr 6) Hallaxa cryptica from Kerama Id, Japan. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/2215Dear Atsushi,
I have never seen this animal alive but from Gosliner & Johnson's description i think you are right in thinking it is Hallaxa cryptica. It is certainly an interesting genus. It seems that each species mimics the sponge that it feeds on.
Best wishes,
Bill Rudman.
