8 — Fan shell, Talochlamys gemmulata

Talochlamys gemmulata, Castlecliff Beach,
Wanganui, 11/89.

Talochlamys gemmulata (Reeve, 1853) is a small fan shell (up to ~50mm) endemic to New Zealand . They are closely related to scallops (Family: Pectinidae) and are found on the continental shelf, down to ~300m depth. They can also live in relatively shallow water and so they do wash up occasionally on beaches. What’s interesting about these particular shells is that they are fossils and were collected (by me) from Castlecliff Beach, Wanganui in November 1989.

There are banks of fossiliferous sediment just up past the dunes at Castlecliff and shells (and other marine fossils) continuously fall out if them. These fossil deposits are thought to date back to at least the Pleistocene, which means that these two shells could be upwards of a million years old. These fossils are morphometrically identical to living populations, so I think it’s interesting to see how little this species has changed.



More info:

http://www.gns.cri.nz/static/Mollusca/taxa/BM488.html

http://www.mollusca.co.nz/speciesdetail.php?speciesid=2280&species=Talochlamys%20gemmulata