Bioacoustics of Helvetia

Description. Small spiders (about 3-6 mm ) with low, elongated carapace and long abdomen ( Fig. 1 ). Abdominal color patterns include pairs of light patches on a dark background, which can be fused forming transverse stripes ( Fig. 1 ), dark abdomen with a large patch of light scales covering the entire abdomen and longitudinal stripes of dark scales on a light background ( Fig. 8 ). Chelicerae about one third of carapace length, almost vertical ( Fig. 1 ), with two teeth on promargin and one on retromargin. Legs Iusually strongest and darkest, strongly developed in some species ( Fig. 1 ). Palps have the heliophanine bump and can have a short embolus, originating distally on the prolateral side of the tegulum and a short RTA ( Figs 15 and 16 ), or can exhibit extensive modifications, such as a very long embolus associated with a counterclockwise rotation of the tegulum in the left palp ( Fig. 19 ), grooves on the cymbium to hold the tip of the curling embolus ( Fig. 18 ), bifid RTA, with a developed ventral branch ( Fig. 20 ) or with a very developed dorsal branch (see GALIANO 1976 , fig. 10). Epigyna vary from very short copulatory ducts ( Figs 4 and 5 ) to coiled, very long copulatory ducts ( Figs 11-14 ), on whose medial part there is a pair of glandular swollen areas; copulatory openings are usually well separated from each other ( Figs 4, 6, 9 , and 13), but can be found close together, forming a median small atrium ( Fig. 11 ) or on the internal wall of a very large, deep atrium ( Figs 21 and 22 ); the epigynal pockets can be fused ( Fig. 4 ), medially placed ( Figs 7 and 10 ) or separated into a pair of lateral pockets ( Figs 12 and 14 ), which can be connected in some species. The stridulatory apparatus consists in this group of a series of three modified setae dorsally on the distal portion of the femur I ( Figs 1 and 3 ) and a granulose area laterally on the anterior portion of the carapace ( Figs 1 and 2 ), extending from the anterior lateral eyes to the region behind the posterior lateral eyes.