Photo taken on Jun 10, 2012

While roaming through Polistovsky, we sometimes observed some small dark creatures running from under the Argo's tracks. We couldn't guess what it is: too small for a chick, too large for an insect (as it was obviously not a beetle or butterfly). Once we were lucky: the dark shadow ran away when the vehicle had just stopped, and I jumped out to find out who was that. After a series of jumps I catched a nice fat raft spider.

Raft spiders and nursery-web spiders belong to the same family Pisauridae (in Russian this family is called “wandering hunters”). There are just a few species of this family in European Russia (most other species are native to tropical Asia), and all of them catch their prey without a web. The raft spiders are semi-aquatic, living near pools of water; when trying to run away from me she dived into the wet sphagnum — in fact under the water. These spiders grow more than 2 cm long and are capable to catch and eat not only an insect but also a tadpole or even a small fish.

species Raft spider Dolomedes fimbriatus