Hello Burton, I certainly can see similarities to the Neritina coromaneliana
(Sowerby, 1836) that Dick Petit suggested [although it's listed from the
Philippines and not Australia as far as I can tell].  However if the shell
really did come from Australia you might consider another possibility
Neritina cf zigzag (Lamarck, 1822). This species is very variable but your
image is very similar to plate 2, #15 a-d [especially 15 B] of Barry
Wilson's Australian Marine Shells Volume 1.  It's listed from Darwin, NW
territories, Australia as well as Pupua New Guinea.  The size listed in
Wilson is smaller at 1.3 cm than your 2.0 cm however.  It's definitely not a
Crepidula [slipper shell].  Maybe someone more expert than I, can solve the
mystery for you?  Bert Bartleson PNWSC

-----Original Message-----
From: Conchologists List [mailto:[log in to unmask]] On Behalf Of
Burton Vaughan
Sent: Monday, September 08, 2008 12:37 PM
To: [log in to unmask]
Subject: [CONCH-L] ID Assistance

I would greatly appreciate help in identifying the following shell,
which was obviously mis-identified in the Archerd Shell Collection:

http://shells.tricity.wsu.edu/ArcherdShellCollection/
QuestionableIDs.html

-Burton Vaughan

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