Sunday, January 27, 2013

TM2499, Sun 27th Jan

Snow gone and valley well flooded, much to the delight of a Little Egret or two (waiting for it's big cousin to turn up...) Just one species today - Common Pill Woodlouse in the woodpile.

Still spending far too long trying to make headway with the numerous small snails here. I use the FSC key (Cameron) and find it very difficult to feel sure at couplet 26 whether to go to Gastrodontidae/Oxychilidae or Helicoidea. I don't find "glossy or waxy" very helpful personally - I guess I just need to look at lots more... Then if I assume it's the former group, I then end up at "Shell with rapidly (or slowly) expanding whorls" and again I find the differences unconvincing. Look at the picture of Aegopinella nitidula on p53 and Oxychilus draparnaudi on p54 - they look pretty similar to me in terms of speed of whorl expansion. Hmm. Time for bed methinks...

2 comments:

  1. I find it quite useful when starting on something new like that to put the names of some of the species into Google images and get an impression of what they look like. The keys are often a little easier to follow once I've got a little more familiar with the range of forms available. Snails are interestingly similar, however, and as I'm just about to start looking at some slugs from my compost bin using the newly acquired slug key I'll probably end up getting just as confused.

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  2. Yeah, good idea Bill thanks. Have done this tonight and whilst not there yet, at least I've ruled a few options out so definitely helpful.

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