7th March 2015 (weekly review)

A very slow week. Only one new species was found. Frustratingly, I managed to find the empty shells on no less than four species that I need to see. I am not yet desperate enough to start counting empty shells but if I get desperate towards the end of the year I might start giving myself half-marks for them.

My one new species this week – species number 21 – was:

Aegopinella pura, the Clear Glass Snail

There are two Aegopinella species in the UK, the other being Aegopinella nitidula. A. nitidula is a very common species, but is easily mixed-up with one of the Oxychilus species. A. pura, on the other hand, is reasonably distinct but less common in my experience. It is a reasonably small snail – max width of just over 4mm – and has a very pleasant ivory/pearl coloured shell. Picture by me:

Whilst I’ve found A. nitidula in gardens and waste ground, I’ve only ever found A. pura in leaf litter or in the bases of very mature hedges. At the Pulpit Hill and Grangelands Nature Reserve, which I visited this week with @RyanClarkNature & @BrianE_Cambs, we found A. pura in quantities far exceedingly the numbers I have seen at any other site ever. Presumably the underlying chalk and deep beech-leaf litter is particularly to their liking.

A good picture by @BrianE_Cambs:

The most distinctive feature of A. pura is the structure of the shell, though you’ll need a x20 lens in order to see it. The shell is marked with radial striations (similarly, but not as strongly as in Nesovitrea hammonis) as well as spiral striations. This means that shell, when viewed closely, has a pattern of what appears to be tiny squares. A picture of this by @BrianE_Cambs:

This week I plan to explore some riverside habitats in the hope of finding species such as Succinea putris, Arianta arbustorum and Zonitoides nitidus. Wish me luck!