For the identification of insects and other fauna and flora of South Africa.

Wednesday, August 8, 2012

Tetragnatha (long-jawed water spiders)

These are very handy spiders to have as their main food is mosquitoes.
 Tetragnatha is a nocturnal and sometimes diurnal spider.
 The integument is cryptically coloured in shades of brown, cream and green for those species that occur amongst foliage. Tetragnatha has an very elongated body. The long chelicerae projects forward with long fangs folded against it. Its body length is rather small as can be seen on the picture of it on a Morning Glory below.
 The delicate orb-web, with few radii and spirals, is usually horizontally inclined over streams or bodies of water. The web is taken down and reconstructed daily and the spider is often found on an incomplete web.
 On the web the spider resembles a piece of dry grass as the front two pairs of legs are projected forward while the back pairs are projected backwards. Tetragnatha has a world distribution and is the most common genus, of the Tetragnathidae, with 14 species in South Africa. The name is derived from the Greek "tetra" means "four" and "gnathos" means "jaws".