Article extracted from Saint Martin | sxminfo.fr http://www.sxminfo.fr/64472/2013/08/18/a-piece-of-st-martin-wild-life-argiope-argentata/ and written by Mark YOKOYAMA.
Tiny Thieves: Spiders Stealing from Spiders
If you look closely at the webs of the Silver Argiope (Argiope argentata) and other large spiders you may find one or more tiny Dewdrop Spiders (Argyrodes spp.). These tiny spiders don’t build their own webs. They live in the webs of larger spiders and steal small insects that are caught. This behavior is known as kleptoparasitism. In some cases, however, it is possible that these spiders help their host keep the web clean by eating prey that is too small for the host.
Although these spiders are tiny, about the size of a grain of rice, close inspection will reveal that they are often quite beautiful. On St. Martin, they have a variety of colors and patterns. Most have abdomens shaped like a drop of water. There may be six or more Dewdrop Spiders living in the web of a single host. The next time you pass a large spider web, take a close look for these tiny thieves.