Wooly-legged Jumping Spider - Saitis barbipes
In accordance with the requirements of courtship in jumping spiders, in which the visual cues are the primary releaser, males of the Wooly-legged Jumping Spider, Saitis barbipes (Salticidae) are highly skilled.
Although most males jumping spiders use their first legs for signaling toward the female, some genera (e.g. Saitis, Maratus, Habronattus) have specialized their third legs for that purpose. In the Mediterranean Saitis barbipes, the third legs, larger than the others, are red and bear conspicuous black hair brushes on tibia and metatarsus. During courtship these legs are waved up and down, and from time to time he makes the white-tipped tarsi vibrate rapidly in a plane perpendicular to the body axis. The vibration frequency is high enough to produce a sound perceivable by man.
Although the male seems extenuated by this performance, the effect on the female is impressive, she collapses on her legs and half turns her abdomen ventral side upward.
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Photo credits: [Top: ©kankikun | Locality: not indicated, 2012] - [Bottom: ©Thomas Roppenecker | Locality: not indicated, 2014]