Bioacoustics of Holocnemus reini

Redescription Male ( Morocco , near Tilamizene, ZFMK Ar 22319) MEASUREMENTS. Total length 6.7, carapace width 1.75. Distance PME–PME 120 µm; diameter PME 120 × 140 µm; distance PME–ALE 50 µm; diameter AME 100 µm; distance AME–AME 25 µm. Leg 1: 38.4 (11.7 + 0.8 + 10.0 + 13.6 + 2.3), tibia 2: 6.9, tibia 3: 5.5, tibia 4: 6.5; tibia 1 L/d: 47; femora 1–4 diameters: 0.31, 0.25, 0.22, 0.23. COLOR (in ethanol). Carapace ochre-yellow; ocular area posteriorly with light brown V-mark; sternum dark brown; legs ochre-yellow, femora and tibiae with light tips and indistinct darker subdistal rings, with black lines on femora and (few) on tibiae, very few also on metatarsi; abdomen with distinct pattern of dark marks and whitish marks dorsally and laterally; ventrally with distinct black median band, partly disrupted, behind gonopore divided by two thin longitudinal light lines. BODY. Habitus as in Fig. 7 . Ocular area slightly raised. Deep thoracic pit and pair of shallow furrows diverging from pit toward posterior margin. Clypeus unmodified but rim more sclerotized than in female. Sternum wider than long (1.10/0.85), with distinct indentations between consecutive leg coxae and between coxae 4 (cf. Fig. 81 ). Abdomen strongly elongated beyond spinnerets, dorso-posteriorly pointed. Gonopore with seven epiandrous spigots ( Fig. 93 ); ALS with one widened spigot and one pointed spigot ( Fig. 94 ). CHELICERAE. As in Figs 64–65 , with pair of low proximal frontal humps and pair of frontal lateral apophyses, each with two large modified cone-shaped hairs; distance between tips of modified hairs: 520 µm; several ‘regular’ frontal hairs with small but distinct processes at basis; lateral stridulatory ridges very fine ( Fig. 84 ; distances between ridges: 2–3 µm), barely visible in dissecting microscope. PALPS. As is Figs 59–61 ; coxa with rounded retrolateral hump; trochanter barely modified; femur slightly curved towards dorsal, distally widened, with rounded ventral protrusion, proximally with prolateral stridulatory pick ( Fig. 86 ), with barely visible retrolateral transversal line, without retrolateral proximal process; femur-patella joints shifted toward prolateral side; tibia very large compared to femur, tibia-tarsus joints shifted toward retrolateral side; tarsus without macrotrichia; procursus ( Figs 62–63 ) straight, few hairs slightly curved upwards; tarsal organ capsulate ( Fig. 87 ); proximally on prolateral side with strong hump free of hairs, procursus tip with distinctive flat membranous element retrolaterally (arrow in Fig. 63 ) covering proximal part of ventral sclerite, with dorsal transversal flap and complex retrolateral elements ( Figs 89–91 ); genital bulb ( Figs 66–68 ) with simple basal sclerite connected to distal (main) sclerite, sperm duct opening in membranous area prolaterally at basis of distal sclerite ( Fig. 92 ); distal sclerite with one large apophysis (fold) and two smaller apophyses on prolateral side; with indistinct retrolateral parallel ridges ( Fig. 68 ). LEGS. Femur 1 with single row of ~24 ventral spines; without curved hairs; few vertical hairs; retrolateral trichobothrium of tibia 1 at 3%; prolateral trichobothrium absent on tibia 1, present on other leg tibiae; tarsal pseudosegments indistinct and irregular except 4–5 distally. Male (variation) Tibia 1 in 73 males : 7.6–12.8 (mean 10.6). Chelicerae maximum width (N = 57): 0.56–0.80 (mean 0.67); distance between tips of cheliceral apophyses: 0.41–0.58; cheliceral apophyses sometimes with 3 modified hairs, sometimes asymmetric (2 and 3 hairs, respectively; Figs 82–83 ). Procursus length (N = 58): 0.82–1.16 (mean 1.03). Coloration of fresh specimens slightly variable, usually with dark median band on carapace. Posterior elongation of abdomen variably long, ~0.5–1.0 × distance pedicel– spinnerets. Gonopore with 6–8 epiandrous spigots. Female In general similar to male ( Fig. 8 ) but without spines on legs; often with slightly longer dorsal abdominal elongation. Without stridulatory apparatus between carapace and abdomen; with fine cheliceral stridulatory ridges as in male ( Fig. 85 ; distances between ridges ~3 µm). Tibia 1 in 53 females : 6.4– 12.5 (mean 9.2). Epigynum as in Figs 71–76 and 96 , main epigynal plate triangular to trapezoidal, weakly protruding; only posteriorly laterally strongly sclerotized; with pair of variably distinct pockets (distance between pockets 0.5–0.6); internal sclerotized arc and median round structure variably visible in uncleared specimens; posterior epigynal plate large but simple; pair of low but distinct elevations in front of epigynum. Internal genitalia ( Figs 69–70 , 77–80 ) with triangular pore plates converging anteriorly, dorsal arc simple and slender, ventral arc laterally strongly widened, medially strong, with simple median pouch. Natural history This species lives in a variety of habitats, ranging from shady pine forests and river valleys to very dry arid slopes. Most specimens were found in sheltered spaces among and under rocks. The large webs (diameter ~ 30 cm ) were often exposed to direct sunlight, but during the day the spiders rested on the shady rock surface. On some occasions, the species was present outside of caves while the caves were occupied by a different species (e.g., SE of Zebzat: Maghreba aurouxi gen. nov. ; Grotte Kef el Ghar: Micropholcus sp. ). On several occasions, H. reini was found on rocks very close to undescribed representatives of Micropholcus , occupying much the same microhabitat (Paradise Valley; Imi n’Ifri; near Ksiba). Near Sidi Ben Daoud, the spiders were extremely abundant in a very dense field of cacti. The domed webs transformed to distinct funnels that led into the barely accessible space among the cacti. High abundances were also reported by Hajer & Řeháková (2003) , who observed “communities of up to several hundred individuals” (vouchers of their “ Crossopriza sp. ” were reexamined; see above). Hajer & Řeháková (2003) also described web construction and the production of silk puffs, which were in principle identical to those of H. pluchei (see above). Unlike, H. pluchei , however, mated females built a more open spotted dome (rather than a sphere) within the main web and left this dome for attacking prey. Also, females tolerated the presence of males inside the dome and copulated repeatedly while still holding the egg sac. After the second molt of the spiderlings, females destroyed the dome and the spiderlings dispersed ( Hajer & Řeháková 2003 ).