| Re: Slug needs a name
The swaying and twisting motion is also a good identification feature - only Arion ater (and its close relative Arion rufus (or Arion ater subspecies rufus, according to some people) can do it.
There are a couple of other large Arion, the Lusitanian Slug A. lusitanicus (often red or dark brown) and the Durham Slug A. flagellus (stripey when young, often green or greyish as adult, but sometimes brown or black; but always opaque creamy white underneath, whereas ater is usually black or dark grey) but they don't show the swaying rocking reflex when disturbed.
So the behaviour can be really useful if you want to name your beast.
You're also right about the breathing hole - it's toward the front of the mantle in round-back slugs, Arion, and toward the back in keeled slugs like Limax and Deroceras.
Cheers
Brian |