Ninetis marnif Huber sp. nov.

urn:lsid:zoobank.org:act: F8745B42-20F4-47BF-978F-85041A099439

Figs 3G, H, 28–33, 34D

Diagnosis. Males are easily distinguished from all known congeners (and the Omani Magana velox) by absence of frontal processes on male chelicerae (Fig. 29G–I; present in all known congeners); also by unique shapes of procursus (Fig. 29C; curved toward dorsal, ventrally semi-transparent) and bulbal processes (Fig. 29F; pointed ventral process and very short membranous dorsal process). Females are distinguished by short anterior epigynal plate (longer in known congeners) without median pocket (otherwise present in all species except N. samail sp. nov. and N. minuta) and pair of internal sclerites directed towards posterior, also visible in uncleared specimens (Fig. 30; in other species straight or curved towards anterior).

Type material. Holotype. OMAN — Dhofar • ♂; W of Al Marnif; 16.8640 °N, 53.7233 °E; 70 m a.s.l.; 24 Feb. 2018; B.A. Huber leg.; ZFMK Ar 24423.

Other material examined. OMAN — Dhofar • 4 ♂, 5 ♀; same collection data as for holotype; ZFMK Ar 24424 • 5 ♀, in pure ethanol; same collection data as for holotype; ZFMK Om 140 • 1 ♀; Ain Hamran; 17.1017 °N, 54.2842 °E; 130 m a.s.l.; 22 Feb. 2018; B.A. Huber leg.; ZFMK Ar 24425 • 1 ♂, 1 ♀, in pure ethanol; same collection data as for preceding; ZFMK Om 129 • 5 ♂, 2 ♀ (1 ♂ used for SEM); Wadi Shalyon; 17.1844 °N, 54.9538 °E; 360 m a.s.l.; 1 Mar. 2018; B.A. Huber leg.; ZFMK Ar 24426 • 8 ♀, in pure ethanol (four prosomata used for molecular work; 1 ♀ used for SEM); same collection data as for preceding; ZFMK Om 149 .

Etymology. The species epithet is a noun in apposition, taken from the type locality.

Description

Male (holotype)

MEASUREMENTS. Total body length 0.93, carapace width 0.38. Distance PME-PME 30 µm; diameter PME 35 µm; distance PME-ALE 20 µm; distance AME-AME 10 µm; diameter AME 15 µm. Leg 1: 1.76 (0.50 + 0.14 + 0.46 + 0.40 + 0.26), tibia 2: 0.38, tibia 3: 0.32, tibia 4: 0.52; tibia 1 L/d: 8; diameters of leg femora 90 µm, of leg tibiae 55 µm.

COLOUR (in ethanol). Prosoma and legs ochre to light brown, carapace without darker pattern; legs without darker rings; abdomen ochre-grey with darker internal marks dorsally and laterally; ventrally with ochre-brown plate in front of gonopore.

BODY. Habitus as in Fig. 3G. Ocular area barely raised. Carapace without thoracic groove (cf. Fig. 31A). Clypeus unmodified, without sclerotized rim. Sternum slightly narrower than long (0.28/0.30), without anterior processes near coxae 1. Abdomen oval to globular; gonopore without epiandrous spigots (Fig. 31E); spinnerets as in congeners (Fig. 31G).

CHELICERAE. As in Fig. 29G–I; without frontal modification; stridulatory files poorly visible in dissecting microscope, consisting of approximately 25 ridges (Fig. 31D), distances between ridges ~1.8 µm.

PALPS. As in Figs 28, 32A, B; coxa unmodified; trochanter ventrally slightly protruding; femur proximally with very indistinct retrolateral protrusion followed distally by shallow depression, with prolateral stridulatory pick, distally slightly widened but otherwise unmodified; femur-patella joints not shifted toward one side; tibia with two trichobothria in relatively distal position; tibia-tarsus joints not shifted toward one side; tarsus with strong dorsal hairs, tarsal organ capsulate (Fig. 32C). Procursus (Fig. 29A–C) small, distally curved towards dorsal, ventrally semi-transparent; genital bulb (Fig. 29D–F) with pointed ventral process and very short membranous dorsal process (putative embolus).

LEGS. Without spines, without curved hairs; with many short vertical hairs on tibia 1 only, in several rows with ~25 hairs each (Fig. 32E; barely visible in dissecting microscope); retrolateral trichobothrium of tibia 1 at 60%; prolateral trichobothrium absent on tibia 1; thin metatarsal hairs present on metatarsi 3 (one hair) and 4 (three to four hairs), in proximal ventral position (cf. Fig. 32F–H); tarsus 1 with ~4 pseudosegments, barely visible in dissecting microscope; tarsal organs on legs 3 and 4 apparently non-functional (Fig. 33C, D). Chemosensory hairs, trichobothria, other tarsal organs, rimmed pores, cuticular plates, and tarsal claws as in congeners (Figs 32, 33).

Variation (male)

Tibia 1 in 11 males (incl. holotype): 0.40–0.49 (mean 0.45).

Female

Females are much lighter than males; this difference is even more pronounced in live specimens (Fig. 3H). Chelicerae without stridulatory files (Fig. 31B), tibia 1 without short vertical hairs. Tibia 1 in 18 females: 0.36–0.46 (mean 0.41). Epigynum (Figs 30, 31F) anterior plate very short, roughly semi-circular, without pocket; posterior plate wide, as long as anterior plate. Internal genitalia (Figs 30, 34D) with pair of distinctive sclerites near median line, directed towards posterior, i.e. covered by posterior epigynal plate; apparently without pore plates.

Intraspecific distances. The genetic (K2P) distances between three sequenced specimens ranged from 13–15% (Table 2). No morphological differences were seen among specimens of the three localities.

Distribution. Known from three localities in Dhofar Province, western Oman (Fig. 4B).

Natural history. The spiders were found by turning rocks in habitats fully exposed to the sun (Fig. 5G, H). At the type locality, the spiders were found running on the ground rather than on the undersides of stones. In Wadi Shalyon, they were beaten from rocks lying on sandy soil. One egg sac contained three eggs with an egg diameter of 0.37.