Bioacoustics of Ninetis amoud

Description Male ( holotype ) MEASUREMENTS. Total body length 0.95, carapace width 0.41. Distance PME-PME 40 µm; diameter PME 45 µm; distance PME-ALE 15 µm; distance AME-AME 10 µm; diameter AME 25 µm. Leg 1: 2.08 (0.60 + 0.14 + 0.53 + 0.51 + 0.30), tibia 2: 0.42, tibia 3: 0.36, tibia 4: 0.62; tibia 1 L/d: 11; diameters of leg femora 80–90 µm, of leg tibiae 50 µm. COLOUR (in ethanol). Prosoma and legs ochre-yellow, carapace median third slightly lighter, without distinct pattern; legs without darker rings; abdomen ochre-brown with small darker internal marks dorsally and laterally; ventrally with indistinct light ochre-yellow plate in front of gonopore. BODY. Habitus as in Fig. 3C . Ocular area barely raised. Carapace without thoracic groove (cf. Fig. 16A ). Clypeus unmodified. Sternum barely wider than long (0.30/0.28), with pair of anterior processes near coxae 1 (~30 µm diameter at basis, 20 µm high). Abdomen oval to globular; gonopore with four epiandrous spigots in two pairs ( Fig. 16E ); spinnerets as in congeners (see genus description above; cf. Fig. 16G, H ). CHELICERAE. As in Fig. 14G–I ; with pair of strongly curved frontal apophyses close together; stridulatory files ( Fig. 16D ) very fine, not visible in dissecting microscope, consisting of approximately 30 ridges, distances between ridges ~1.3 µm. PALPS. As in Figs 13 , 17A–D ; coxa unmodified; trochanter with small ventral process; femur proximally with indistinct retrolateral hump, with prolateral stridulatory pick ( Fig. 17E ), on ventral side with tiny tubercles ( Figs 13 , 17A ), distally slightly widened but otherwise unmodified; femur-patella joints shifted toward prolateral side; tibia with two trichobothria in relatively distal position; tibia-tarsus joints slightly shifted toward retrolateral side; tarsus with strong dorsal hairs; procursus short and simple ( Fig. 14A–C ), strongly bent towards prolateral at approximately one third of its length, distally membranous; genital bulb ( Fig. 14D–F ) with long ventral process, dorsal process with distinctive flattened sclerite (wide in dorsal view) provided with sclerotized ventral ridges, and short putative embolus with membranous and sclerotized elements. LEGS. Without spines, without curved hairs; with short vertical hairs ( Fig. 18G, H ) on tibia 1 only; retrolateral trichobothrium of tibia 1 at 60%; prolateral trichobothrium absent on tibia 1; thin metatarsal hairs present on metatarsi 3 and 4 (one each, in proximal ventral position; cf. Fig. 18E ); tarsus 1 with ~5 pseudosegments, barely visible in dissecting microscope; anterior tarsal organs as in congeners ( Fig. 19A–C ), those of leg 4 apparently non-functional ( Fig. 19D ); chemosensory hairs, rimmed pores, cuticular plates, and tarsal claws as in congeners ( Figs 18–19 ). Variation (male) Tibia 1 in 47 males (incl. holotype ): 0.46–0.60 (mean 0.53). Dark marks on abdomen variably distinct. Female In general very similar to male but usually lighter than male (orange rather than ochre), sternum unmodified, chelicerae without stridulatory files ( Fig. 16B ), tibia 1 without short vertical hairs. Tibia 1 in 70 females : 0.47–0.64 (mean 0.54). Palp ends distally in simple sclerotized tip ( Fig. 18A ). Spinnerets as in male. Epigynum ( Figs 15 , 16F ) anterior plate trapezoidal, with median pocket opening medially on anterior epigynal plate and directed towards anterior; with variably distinct anterior ridge; with pair of strong transversal internal sclerites visible through posterior epigynal plate; posterior plate wide and short. Internal genitalia ( Fig. 15 ) with pair of transversal sclerites and complex median structures, apparently without pore plates. Intraspecific distances. The genetic (K2P) distances between four sequenced specimens ranged from 3–17% ( Table 2 ). There was no apparent pattern between geographic and genetic distances: specimens from SW of Mecca and from E of Muhayil (distance 410 km ) had a K2P distance of only 3%; SW of Mecca versus NE of Ghran: 80 km , 12%; E of Muhayil versus NE of Wadi ‘Amoud: 130 km , 17%. No morphological differences were seen among specimens of these localities.