There are two pairs of lyriform
organs and three pairs of needle-like sternal setae [St1 (30-36), St2 (54-60), St3 (60-66)], and St3 is the longest.
Two pairs of lyriform fissures situated on sternal shield, first pair near to St1, second pair near to St5.
Two pairs of lyriform fissures situated, first pair near to St1, second pair between St4 and St5 (Fig.
Median endocarina absent; epicranial stem present but very short; frontal sutures lyriform, strongly curved; bases contiguous.
Median endocarina and epicranial stem very short; frontal sutures lyriform, strongly curved; bases contiguous.
salei needs proprioceptive information for homing because animals that have been surgically altered (e.g., spiders with the lyriform
slit sense organs of the femur and tibia destroyed mechanically) returned with less success to the site from which they had been chased.
The distribution of trichibothria and lyriform
organs on the legs of spiders with different habits.
Two pairs of lyriform fissures present near pedofossae of leg IV.
Sternal shield smooth and bearing one pair of lyriform fissures near base of St1.
They sense mechanical stress in the exoskeleton caused by vibrations, gravity or the spider's own movement and occur singly ('slit sensillae') or in groups where slits run parallel to each other ('lyriform
organs') (Foelix 1996).
This has been shown to be the case in the homing of the ctenid spider Cuppiennius salei Keyserling 1877 which can return to its refuge using only information gathered from the lyriform
organs (Seyfarth & Barth 1972).