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Anyphaenid sac spider

Sac spiders
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Scientific classification
Kingdom:Animalia
Phylum:Arthropoda
Class:Arachnida
Order: Araneae
SuborderAraneomorphae
FamilyAnyphaenidae
Genera
Anyphaena
Hibana

Aysha velox. This specimen was found on the floor of a house in North Carolina, USA. The eyes of this species are especially reflective. They generally sit quietly, even if approached fairly closely, but once they decide to flee they can move with great rapidity. This is not the species known as the "yellow sac spider."

The anyphaenid sac spiders of the family Anyphaenidae are distinguished from the sac spiders and other spiders by having the abdominal spiracle placed one third to one half of the way anterior to the spinnerets toward the epigastric furrow on the underside of the abdomen. In most spiders the spiracle is just anterior to the spinnerets. Like clubionids, anyphaenids have eight eyes arranged in two rows, conical anterior spinnerets that touched and are wandering predators that built silken retreats, or sacs, usually on plant terminals, between leaves, under bark or under rocks. There are more than 500 species in over 50 genera worldwide. The family is widespread and includes such common genera as Anyphaena(worldwide except tropical Africa and Asia) and Hibana (New World). Species in the latter genus are important predators in several agricultural systems, especially tree crops. They are able to detect and feed on insect eggs, despite their poor eyesight. They share this ability at least with some miturgid spiders.

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01-04-2007 01:18:14
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