Menemerus nigli Wesolowska & Freudenschuss, 2012

Ali, Pir Asmat, Maddison, Wayne P., Zahid, Muhammad & Butt, Abida, 2018, New chrysilline and aelurilline jumping spiders from Pakistan (Araneae, Salticidae), ZooKeys 783, pp. 1-15 : 1

Menemerus nigli Wesolowska & Freudenschuss, 2012 Figs 5-13

Notes.

This species was described by Wesołowska and Freudenschuss (2012) based on a male from Baluchistan Province, Pakistan, and redescribed (also from the male) by Chatterjee et al. (2017) from India. In our collecting, we found a male matching M. nigli in close proximity and in similar habitat to a female of similar size and markings. As no other species of Menemerus has yet been collected from Pakistan, except the distinctly different M. bivittatus (Dufour, 1831) and M. marginatus (Kroneberg, 1875) ( Bauer et al. 2015), we interpret the female collected to be that of M. nigli . The female is described for the first time.

Description.

Male (from Pakistan: Khyber Paktunkhwa: Karak (Karak city), 33.11°N, 71.08°E, elev. 550 m, 29 July 2015, Pir Asmat Ali, specimen PAA#2015-07-081). Carapace length 2.72, width 2.06, height 1.12. Abdomen length 2.35, width 2.06. Palp as in the figures of Wesołowska and Freudenschuss (2012). Embolus longer than in most Menemerus species, curved. A membranous "conductor" beside the embolus leads to a membranous area that forms a groove separating the embolus from the tegulum. Tibial apophysis elongate and fairly thin, pointing somewhat ventrally (Figs 7-8). Prolateral side of tibia swollen ( Wesołowska and Freudenschuss 2012, figure 6). Cymbium with short white setae; femur with long brown and white hairs. Body and face as in Figs 5-6.

Female (from Pakistan: Khyber Paktunkhwa: Karak (Serekhawah), 33.27°N, 71.21°E, elev. 509 m., 29 July 2015, Pir Asmat Ali, specimen PAA#2015-07-086), Measurements: Carapace: length 2.82, width 2.06, height 1.31. Ocular area widest at AER; ocular area length 1.41, width of PLE row 1.59, width of PME row 1.50, AER width 1.76. Abdomen: length 3.76, width 2.16. Leg I: coxa 0.65, trochanter 0.47, femur 1.50, patella 0.84, tibia 1.03, metatarsus 0.75, tarsus 0.47. Leg II: coxa 0.56, trochanter 0.37, femur 1.31, patella 0.75, tibia 0.94, metatarsus 0.75, tarsus 0.37. Leg III: coxa 0.65, trochanter 0.37, femur 1.50, patella 1.08, tibia 1.22, metatarsus 0.47, tarsus 0.56. Leg IV: coxa 0.75, trochanter 0.37, femur 1.59, patella 0.84, tibia 1.41, metatarsus 1.12, tarsus 0.56.

Structure. Carapace flat in the cephalic region, dropping down to a lower thoracic area. Chelicerae stout, unidentate, with two promarginal teeth and long fangs. Posterior lateral spinnerets longer than others. Epigynum (Figs 11-13) with broad atria (Figure 11, "At") opening toward the anterior, on the inner (dorsal) wall of which is a sharp fold (Figure 11, "F"), which may serve to guide the entrance of the embolus. The precise point at which the atrium becomes narrowed into the copulatory duct is unclear, but it appears that the path of the embolus (or sperm) would be toward the posterior initially in the broad atrium, then turning medially, and once at the midline then turning posteriorly, at that point clearly in the copulatory duct. Spermatheca touching at midline, overlapped. Fertilization duct long.

Colour (Figs 9). Carapace brown, with cephalic sides dark brown covered by brown and white bristles and a basal band of white hairs. Ocular area black with brown and white bristles. Face black with short and long white bristles; chelicera almost black. Sternum yellow-brown. Legs brown to yellowish brown, metatarsus and tarsus palest; leg I darkest. Dorsum of abdomen with indistinct brown to cream markings, in the anterior half forming a darker longitudinal medial band near the base flanked by two whitish bands, and in the posterior half having a medial whitish patch. Venter is grey with scattered white hairs. Spinnerets yellow.

Remarks.

The female of Menemerus nigli can be distinguished from other Menemerus species by the broad forward-opening atria from which extend distinctive folds (Figure 11, "F"). There are other species with broad atria that open more or less to the anterior, but in most the atria are less deep and more laterally-facing: Menemerus marginatus (Kroneberg, 1875) (see Bauer et al. 2015), Menemerus minshullae Wesołowska, 1999 (see Wesołowska 1999), and Menemerus rubicundus Lawrence, 1928 (see Wesołowska 1999). The epigynum of Menemerus namibicus Wesołowska, 1999 is perhaps most similar to M. nigli , in that the atria face directly to the anterior, but they are not so spacious, and the distinctive fold of M. nigli is lacking ( Wesołowska 1999).