Gastropod torsion

March 19, 1999
From: Manjit Hansra

I saw the page you had on the nudibranch torsion of gills, but was wondering if you had any additional information on gastropod torsion in general. Any additional discussion upon its evolutionary history and variety of opinions for its existence would be very helpful.

Thank-you for your time,
Manjit Hansra

Hansra, M., 1999 (Mar 19) Gastropod torsion. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Dear Manjit,
I am afraid an account on gastropod torsion in general, although very interesting, is a bit outside the scope of the Forum. If I had the time I would love to answer general mollusc questions but I don't. I have mentioned a number of times a new 2 volume book on molluscs which was published last year in Australia called Mollusca: The Southern Synthesis. Despite its name, it covers all the mollusc families worldwide and has introductory chapters on all aspects of mollusc evolution. Unfortunately it is a bit expensive but all good libraries should be urged to get a copy.

If you are interested there is a description of the book on Dave Behrens, Sea Challengers online bookshop at (California) and at Patty Jansen's Capricornia Publications at (Sydney, Australia).

Two useful recent references would be:
Haszprunar, G. (1988). On the origin and evolution of major gastropod groups, with special reference to the Streptoneura (Mollusca). Journal of Moulluscan Studies, 54: 367-441.

Ponder, W.F. & Lindbergh, D.R. (1997) Towards a phylogeny of gastropod molluscs. Zoological Journal of the Linnean Society, London, 19(2): 83-265.

Best wishes,
Bill Rudman.

Rudman, W.B., 1999 (Mar 19). Comment on Gastropod torsion by Manjit Hansra. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Related messages

  1. Torsion & nudibranch gills
    From: Hilda Norris, October 28, 1998

Show factsheet and all related messages