Pale form of Phidiana hiltoni

May 10, 2006
From: Elijah Woolery

Hello-

I found a couple of these specimens in the intertidal, just wondering if they are Hermissenda crassicornis (if so, I've never seen this color morph). Thanks for your help!

 Locality: Fitzgerald Marine Reserve, 1 m, California, USA. 24 April 2005. rocky intertidal Length: 20 mm? Photographer: Elijah Woolery.

Elijah Woolery
www.outofthedeepblue.com

eli@outofthedeepblue.com

Woolery, E.W., 2006 (May 10) Pale form of Phidiana hiltoni. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16474

Hi Eli,
Thanks for the interesting shots.  Your species is actually Phidiana hiltoni.  Normally Phidiana has a red line across the front of the head making it extremely easy to identifiy.  Your specimens are very light colored, kind of faded, and therefore for some reason lack this line.

Note however, they do have the characteristic red band on the lower portion of the rhinophores, and white on the upper half.  Also, the cerata have dark core with yellow tips.

Hermissenda on the other hand always has the distinctive yellow-gold line down the center of the dorsum, flanked by blue.  Also, the rhinophores in Hermissenda have a few irregular rounded rings or annulae, while in P. hiltoni the rhinophores are perfoliate [having many thin closely packed lamellae].

We always enjoy seeing extreme cases of color.  Keep up the good work.
Thanks again,
Dave Behrens

Rudman, W.B., 2006 (May 10). Comment on Pale form of Phidiana hiltoni by Elijah Woolery. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16474

Factsheet

Phidiana hiltoni

Related messages

  1. Re: Phidiana hiltoni with 4 rhinophores
    From: Blair Carmichael, June 30, 2006
  2. Phidiana hiltoni with 4 rhinophores
    From: Blair Carmichael, April 21, 2006
  3. A sea slug? from California
    From: Mila Zinkova, March 3, 2006
  4. Phidiana hiltoni north of Monterey, CA
    From: Ken-ichi Ueda, August 24, 2005
  5. Phidiana hiltoni from the Channel Islands, California
    From: Bruce Wight, August 9, 2005
  6. Phidiana hiltoni from California
    From: Bruce Wight, September 30, 2001
  7. Phidiana hiltoni feeding
    From: Bruce Wight, July 15, 2000
  8. Phidiana hiltoni fighting
    From: Bruce Wight, July 15, 2000

Show factsheet and all related messages