Re: A Californian mystery

December 11, 1998
From: Rebecca Johnson

Dear JM and Dr. Rudman,
Concerning JM's Dec 1st message: I think the large molluscs JM has found on the beach in Monterey, CA are chitons. From his description they sound like dead Cryptochiton stelleri. This is the largest chiton in the world. It has internal valves and a hard, rough, reddish brown mantle. I have seen them washed up on the beach many times and they look a bit like American footballs. I could not find a web site with a picture of the live animal, but maybe someone else can. I hope this helps.
Rebecca Johnson

Johnson, R., 1998 (Dec 11) Re: A Californian mystery. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Thanks Rebecca,
It's a pity anything dead and dishevelled gets called a "slug". Certainly a Cryptochiton would fit the bill. I didn't realise they got so large in your part of the world .. but I guess it is California!

Rudman, W.B., 1998 (Dec 11). Comment on Re: A Californian mystery by Rebecca Johnson. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Related messages

  1. Strange thing in my tank
    From: Brandon Buys, March 3, 2010
  2. A slug-like chiton
    From: John Markby, November 13, 2009
  3. Dorid-like chiton from Moss Beach, California
    From: John Albers-Mead, December 18, 2006
  4. Some type of sea slug?
    From: Chris Fourness, July 8, 2006
  5. Re: Sluglike shelled creature from South Africa
    From: Dawn Ahomed, March 15, 2006
  6. Sluglike shelled creature from South Africa
    From: D. Ahomed, March 13, 2006
  7. Unidentified Canadian Sea Slug?
    From: Jess Trueman, January 14, 2004
  8. Slug? on live rock
    From: Manuel Marquez, January 9, 2004
  9. Mystery from Washington State, USA
    From: Julie, November 14, 2003
  10. Re: Chiton or slug?
    From: Frans Slieker, January 29, 2003
  11. Alien in my tank
    From: Anders Olausson, January 15, 2003
  12. Chiton or slug?
    From: Dee Ryden, November 27, 2002
  13. Re: A Californian mystery
    From: Peter Firminger, December 11, 1998
  14. A Californian mystery
    From: JM, December 1, 1998

Show factsheet and all related messages