Bioacoustics of Aetana libjo

Description Male ( holotype ) MEASUREMENTS. Total body length 3.1, carapace width 1.1. Leg 1: 37.4 (9.0 + 0.5 + 8.8 + 16.2 + 2.9), tibia 2: 5.1, tibia 3: 3.3, tibia 4: 4.8; tibia 1 L/d: 74. Distance PME-PME 270 µm , diameter PME 125× 95 µm , distance PME-ALE 20 µm ; AME absent. COLOR. Carapace ochre-yellow with black lateral margins, dark mark behind ocular area and dark median mark on posterior rim; ocular area and clypeus pale ochre; sternum bright orange; leg coxae ochre-yellow, other leg segments greenish-ochre (especially femora) to light brown (distal segments); abdomen grey with distinct dorsal and lateral pattern of black marks, ventrally with brown band between gonopore and spinnerets (mid-section indistinct). BODY. Habitus as in Fig. 8 ; ocular area slightly raised, each triad on low hump directed toward lateral; carapace only anteriorly with very shallow and narrow median furrow; clypeus barely modified, indistinct median process near rim provided with some slightly stronger hairs; sternum wider than long (0.70/0.55), unmodified. Gonopore with four epiandrous spigots in two pairs ( Fig. 37 ). ALS as in female ( cf . Fig. 36 ). CHELICERAE. As in Fig. 40 , with pair of ridge-shaped apophyses distally near median line, without proximal lateral apophyses; without modified hairs; without stridulatory ridges. PALPS. As in Figs 26–27 , coxa unmodified, trochanter on retrolateral side with large apophysis fused to femur; femur with small retrolateral process distally; tibia length/width: 0.50/0.22; retrolateral trichobothrium on tibia very distal; tarsus with semitransparent simple procursus directed toward patella; tarsal organ exposed ( Fig. 35 ); genital bulb large, with small retrolateral process proximally and three distinctive processes distally ( Figs 30–31, 33 , 38–39 ): dorsal process with distal hook; central hinged process with large prolateral flap and complex tip; ventral hinged process with simple pointed tip. Location of sperm duct opening unknown. LEGS. Without spines, with curved hairs on metatarsi, with vertical hairs in higher than usual density in one retrolatero-dorsal row on each tibia; retrolateral trichobothrium on tibia 1 at 2%; prolateral trichobothrium absent on tibia 1, present on other tibiae. Tarsus 1 with ~30 pseudosegments, distally distinct. Tarsus 4 comb-hairs with very dense tines ( Fig. 32 ). Male (variation) Tibia 1 in 6 other males: 8.3–9.0 (mean 8.6); ratio of palpal tibia length/width: 2.1–2.4. Some specimens with white marks on abdomen in addition to black marks. Female In general similar to male ( Fig. 9 ); eye triads closer together (distance PME-PME 215 µm ); clypeus unmodified; tibiae with short vertical hairs in low density; entire median area of carapace darker; clypeus also slightly darker; abdomen with or without white marks; tibia 1 in 9 females : 6.2–7.2 (mean 6.7). Epigynum with large, weakly sclerotized area, posteriorly protruding with short, narrow scape ( Figs 28 , 45–46 ); internal genitalia with large median membranous structure of unknown function ( Fig. 29 ).