Shells 1 – Trochus virgatus

In recent weeks I have been undertaking frequent circuits of the island to count turtle tracks. This has also given me the opportunity to note the various species of shells that are washed up at high tide. One of the projects under the island’s biodiversity plan is to survey the marine life on the surrounding reef flats and whilst that activity is not scheduled for another couple of years, identification of shells on the beach is as good a starting point as any.

Of course many of the shells washed up are old or damaged and not of sufficient quality for good photographs to be taken such that readers can readily identify the species in question from the photo on the blog. So in each case I will only post on a species when I encounter a good quality and characteristic shell specimen.

So I start today with Trochus virgatus. The Trochidae are a family of medium to large sea snails with conical shells that typically graze on algae though some eat sponges. T. virgatus is very similar to T. maculatus with one of the key differences being that the columella of maculatus is toothed. Jarrett (2000) states that T. virgatus is common in Seychelles being typically found in secure niches on the open reef.

Simply click on the photos below to enlarge.

(Photos J Nevill 2008).

Jarrett, A.G. (2000): Marine Shells of the Seychelles. Carole Green Publishing, Cambridge, UK. ISBN 1 903479 00 2