I met some relatives of my beloved leatherleaf slugs in the mangroves of Singapore, the onch slugs! they’re perhaps some of the slowest-moving animals I’ve ever encountered; this is one in a hurry:
the species pictured is a Platevindex, which are particularly interesting to me since their backs are studded with extra eyes! the dorsal papillae each have a little black dot that’s a photoreceptor, which helps the slug detect changes in light exposure.
onchidiids are marine animals, living on costal rocks and in mangroves, but breathe air and spend much of their time out of the water. like the leatherleafs, they’ve got a dry, tough hide that maintains water balance, but Platevindex takes that to an extreme—when I picked one up, it felt like a vulcanized rubber tire!