you please help me identify this shell I find in the archaeological deposits
of Niah Cave, Sarawak, N. Borneo. I also find it living today in the lowland
freshwater streams just outside the cave. The identification of this will
help the imminent completion of my PhD thesis.
Send thoughts and
Mark Stephens BSc MSc
Department of Geography
University of London
Hmmm... looks like a cerithioid
to me, possibly a member of Pleuroceratidae (or is it Pleuroceridae
that is correct?), with its lack of a sharply-defined canal (pleuroceratids
have a subtle spoutlike labral flexure for a canal); Thiaridae and
Melanopsidae have sharply-defined canal.
Too big for any hydrobiid I know of... if he has any spares, I'd be
interested, esp with operc! (and any other spp he comes across...).
Not a viviparid (I think!) or ampullariid.
This looks more like a hydrobiid
to me as there are several similar but much smaller shells from Thailand/Vietnam.
- will need to chech litterature
The mystery shell from the Niah
Cave and aquatic biotopes in Sarawak is a species of Paludomus (Fam.
Pleuroceridae, suffamily Paludominae). Several species have been recorded
from Borneo in general and Sarawak in particular: luteus H. Adams,
1874 (=moreleti Issel, 1874), isseli Brot (=crassus Issel,1874 not
von dem Busch); persolida Issel, 1874 (=borneensis Nevill, 1884) and
I have a specimen of Balanocochlis glandiformis
(Schepman, 1896). It is similar in every respect, but a bit eroded
on the spire. It came from near Sandakan, Sabah, Malaysia, in small
stream on mud in rainforest, June 24, 1990, collected by Stephanie
Clark. There is an image up at http://members.aol.com/Mkohl2/Pleuroceridae.html
, but looking at the specimens in hand, they look much more like your
excellent photos than the scans up on that page do.
Thank you for your interest,