Diving bell spider
Genus of spiders
The diving bell spider or water spider (Argyroneta aquatica) is the only species of spider known to live almost entirely under water. It is the only member of the genus Argyroneta and the type genus of the family Argyronetidae. When out of the water, the spider ranges in colour from mid to dark brown, although the hairs on the abdomen give it a dark grey, velvet-like appearance.
From Wikipedia, under CC BY-SA. More on occurri.