Bioacoustics of Agyneta unguiserrata

Description. Male ( Holotype FCE–Ar 13431) Total length: 1.76; carapace length: 0.79, width: 0.62; abdomen length: 0.96, width: 0.64. CEPHALOTHORAX: Eyes diameters and interdistances: AME: 0.05, PME: 0.06, ALE: 0.07 and PLE: 0.07; AME–ALE: 0.05, PME–PLE: 0.05, AME–AME: 0.03, PME–PME: 0.03. Eyes margined with black, suffused with black between AME and between ALE and PLE. Carapace ovoid, longer than wide, brown. Labium light brown. Sternum dark brown to light brown in the center, with scattered setae. Clypeus height: 0.13. Chelicerae length: 0.29; light brown; seta-tipped tubercles absent; promargin three denticles and pointed projection, retromargin one denticle and pointed projection near the base of the fang. Cheliceral stridulatory organ ~70 striae, uniformly spaced ( Fig. 6A ). ABDOMEN: Elliptic, longer than wide, dorsally dark gray with a medial transverse light gray stripe and light gray spot both anteriorly and posteriorly, ventrally dark gray to brown in the center ( Figs 3G–H ). Spinnerets and colulus dark gray. LEGS: light orange; leg I total length: 3.08; leg III total length: 2.55; Tm I: 0.28, Tm IV: absent. GENITALIA: Palpal retrolateral tibial apophysis pointed and sclerotized, with denticles in the retrolateral margin ( Figs 3A , 6B ); dorsal tibial apophysis highly developed, fanglike, with denticles in the retrolateral margin; two retrolateral trichobothria and a dorsal one ( Figs 3A , 6B ). Cymbium rounded; glabrous depression present, retrolateral cymbial tubercle rounded and smooth; dorsal cymbial tubercle truncated and smooth; ventral cymbial tubercle slightly acute and smooth ( Figs 3A–B , 6B–C ); membranous region present ( Figs 3A , 6B ); prolateral notch absent ( Fig. 3B ). Paracymbium apical pocket large; anterior pocket large, triangular, and membranous; posterior pocket absent ( Figs 3A , 6B ). Embolus tip pointed ( Figs 3B–C ); Fickert’s gland basal, elongated ( Fig. 3C ); ventral lamella smooth and hooked Fig. 3C ); thumb short, well below the embolus proper ( Fig. 3C ). Embolus proper peak rounded and set apically in the embolus ( Fig. 3C ). Anterior terminal apophysis membranous, long, wide and apically crenated ( Fig. 3D ); posterior terminal apophysis basal extension large, membranous, trisected and ensiform with thorns ( Figs 3D , 6B, 6D ); posterior terminal apophysis highly sclerotized and spiky ( Fig. 3D ); posterior terminal apophysis prong longer than wide and apically dentated ( Fig. 3D ); lamella characteristica longer than wide, with a lobe near the apex and thorns in the distal part ( Figs 3A, 3D , 6B, 6D ). Female paratype (FCE-Ar 13621). Total length: 1.40; carapace length: 0.59, width: 0.52; abdomen length: 0.86, width: 0.63. CEPHALOTHORAX: Eyes diameters and interdistances: AME: 0.05, PME: 0.06, ALE: 0.07 and PLE: 0.07; AME–ALE: 0.02, PME–PLE: 0.02, AME–AME: 0.01, PME–PME: 0.02. Eyes margined with black, suffused with black between AME and between ALE and PLE. Carapace ovoid, longer than wide, brownish orange. Labium brown. Sternum brown, with scattered setae. Clypeus height: 0.11. Chelicerae length: 0.32; brownish orange; seta-tipped tubercles absent; promargin four denticles, retromargin five denticles. Cheliceral stridulatory organ ~54 striae, narrowly spaced throughout ( Fig. 6C ). ABDOMEN: Elliptic, longer than wide, dark gray with median and posterior transverse gray stripe ( Figs 4E, 4F ). Spinnerets and colulus dark gray. LEGS: light orange, leg I total length: 2.62; leg III total length: 2.22; palpal tarsal claw absent; Tm I: 0.32, Tm IV: absent. Colulus present. GENITALIA: Epigynum with proximal part of scape triangular (margins convex and widen to the anterior part), longer than tall, with two conspicuous elliptical processes ( Figs 4A, 4B , 7D ); epigynal slits crescent; lateral lobes elongated and crescent in the extremes; pit hook depression absent; stretcher elongated ( Fig. 4A , 7D ). Median part of the scape long and wide; genital pores at the base of lateral lobes pockets ( Fig. 4C ). Internal genitalia with a large, reniform dorsal receptacula ( Figs 4B–D ). Variation. Total length ( 6 males ): 1.76–2; carapace length: 0.77–0.87, width: 0.60–0.67; leg I total length: 3.08–3.52; leg III total length: 2.29–2.64. Total length ( 6 females ): 1.40–2.04; carapace length: 0.59–0.79, width: 0.47–0.55; leg I total length: 2.62–3.28; leg III total length: 2.04–2.49. Coloration in females is quite variable. Some individuals lack the median transverse and posterior dark gray stripe in the abdomen and have a uniform pale gray abdomen. Natural history: Agyneta unguiserrata n. sp. was found in natural grasslands and riparian forests. Males were collected using pitfall traps, G-Vac, looking down and beating tray, females with pitfall traps.