05 January 2009

News from the slugarium—Part 2

In yesterday's post I wrote about a fallen beech tree that was covered with the feeding tracks of the slug Megapallifera mutabilis. The 2 slugs I have been keeping for about a week now happen to be the same species. So over the last weekend I decided to generate some "homemade" feeding tracks. From the fallen tree I got a nice piece of beech densely covered with cyanobacteria (green algae), put in my slugarium early in the evening and placed one of the slugs on it. This is what I had the next morning.

MegapalliferaTracks1

Interestingly, the slug formed a complete loop. It started out near the upper right-hand corner where I had placed it next to the black object (which is a piece of fecal string), crawled to the other end, turned around and crawled back to its starting point, then it stopped feeding and left the wood. Disappointingly, however, it left only a few teeth marks on the bark and those were difficult to spot (arrows).

MegapalliferaTracks2

I don't know why these slugs sometimes leave distinct marks (see the pictures in yesterday's post) and sometimes don't. Also, after discussing this with Megan, now I am not sure if those marks are made by the radular teeth or the ribs on the jaws. There will be more on that in the future.

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