Bioacoustics of Austrohahnia catleyi

Description. Female holotype ( Figs 2A, B, H, I ; 3G–I; 4E, F). Total length 3.84. Carapace 1.75 long, 1.26 wide; abdomen 2.34 long, 1.70 wide. Eye sizes and interdistances: AME 0.08, ALE 0.11, PME 0.10, PLE 0.10. AME–AME 0.04, ALE–ALE 0.19, PME–PME 0.07, PLE–PLE 0.32, AME–PME 0.08, ALE–PLE 0.02. Clypeus height 0.17, clypeus height at AME 0.25. Chelicerae with weak stridulatory files laterally; three promarginal and three retromarginal teeth. Sternum slightly wider than long. Leg measurements: I 4.51 (1.27, 1.47, 1.02, 0.75); II 4.38 (1.25, 1.42, 1.01, 0.70); III 4.36 (1.25, 1.34, 1.10, 0.67); IV 5.54 (1.55, 1.72, 1.47, 0.80). Carapace dark brown, slightly lighter near the edges, edges black. Sternum dark brown, somewhat lighter in the middle. Abdomen with pale yellow chevrons dorsally along the abdomen ( Figs 2A , 4E, F ); ventrally brown with lighter irregular spots ( Fig. 2B ). Legs pale yellow with dark brown rings. Epigyne with two somewhat spherical copulatory opening, located in medium atrium ( Figs 2H ; 3G); middle stretch of copulatory duct converging toward the middle ( Fig. 3H ). The secondary receptacle not close to copulatory opening ( Fig. 3I ). Variation (n = 5): total length 3.14–4.00, mean 3.62; one female from Salta has slightly shorter middle stretch of copulatory duct. Male paratype (MACN-Ar 30194) ( Figs 2C–G ; 4G, H). Total length 2.75. Carapace 1.40 long, 1.10 wide; abdomen 1.45 long, 1.04 wide. Eye sizes and interdistances: AME 0.05, ALE 0.10, PME 0.09, PLE 0.08. AME–AME 0.04, ALE–ALE 0.16, PME–PME 0.07, PLE–PLE 0.27, AME–PME 0.07, ALE–PLE 0.02. Clypeus height 0.14, clypeus height at AME 0.22. Chelicerae, sternum and abdomen as in female. Leg measurements: I 4.27 (1.15, 1.35, 1.00, 0.77); II 4.17 (1.15, 1.30, 1.00, 0.72); III 4.04 (1.05, 1.25, 1.05, 0.69); IV 4.98 (1.25, 1.56, 1.35, 0.82). Femora uniformly dark brown (in nature looking metallic; figure 4G, H). Other characters as in female. Palp ( Figs 2E–G ): patellar apophysis without granulated edge; copulatory bulb and embolus with the configuration of the genus ( Figs 2F, G ). Variation (n = 3): total length 2.40–2.76, mean 2.64. Natural history ( Figs 4E–H ). Austrohahnia catleyi new species inhabits litter of alder forests ( Alnus acuminata Kunth ) in Northwestern Argentina to over 1700 m altitude, where it builds small horizontal sheet-webs with a retreat. These spiders are very fast and hide rapidly at the slightest disturbance, so they are hard to find among the dry leaves on the ground. Some males were observed wandering on the female webs, approaching slowly towards the retreat.