Ninetis samail Huber sp. nov.

urn:lsid:zoobank.org:act: 6A336EF2-1ED5-4A86-8F2A-F6D2F878FB16

Figs 3E, F, 21–27, 34C

Diagnosis. Males are easily distinguished from all known congeners (and the Omani Magana velox) by presence of unique spine (macroseta) on procursus (Fig. 22C; absent in other species); also by distinctive set of sclerotized processes on genital bulb (Fig. 22D–G; complex flat ventral process and sclerite on dorsal process with small teeth; known congeners and M. velox with simple ventral sclerotized process) and by pair of long frontal apophyses on chelicerae close together (Fig. 22H–J; in other species shorter and/or wider apart). Females externally very similar to known congeners but epigynum without median pocket ( N. marnif sp. nov. similar but with much shorter epigynum); also distinguished by presence of pair of large membranous elements in internal genitalia (Figs 23, 34C; absent in other species).

Type material. Holotype. OMAN — Ad Dakhiliyah • ♂; near Samail; 23.309 °N, 57.940 °E; 440 m a.s.l., 14 Feb. 2018; B.A. Huber leg.; ZFMK Ar 24419.

Other material examined. OMAN — Ad Dakhiliyah • 3 ♂, 2 ♀ (1 ♂ used for SEM); same collection data as for holotype; ZFMK Ar 24420 • 2 ♂, 4 juvs, in pure ethanol; same collection data as for holotype; ZFMK Om 100 • 1 ♂, 2 ♀; near upper entrance of Al Hoota cave; 23.101 °N, 57.374 °E; 1040 m a.s.l.; 16 Feb. 2018; B.A. Huber leg.; ZFMK Ar 24421 • 3 ♀, 7 juvs, in pure ethanol (4 juvs used for molecular work; 1 ♀ used for SEM); same collection data as for preceding; ZFMK Om 109 • 3 juvs, in pure ethanol (identity confirmed with CO1); Wadi Sact; 23.0632 °N, 58.0464 °E; 820 m a.s.l.; 17 Feb. 2018; B.A. Huber leg.; ZFMK Om 111 .

Ash Sharqiyah North • 1 ♂, 1 ♀; between Al Rawda and Al Hayema; 22.880 °N, 58.293 °E; 690 m a.s.l.; 17 Feb. 2018; B.A. Huber leg.; ZFMK Ar 24422 • 1 ♀, 5 juvs, in pure ethanol; same collection data as for preceding; ZFMK Om113 .

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

Description

Male (holotype)

MEASUREMENTS. Total body length 1.00, carapace width 0.44. Distance PME-PME 45 µm; diameter PME 40 µm; distance PME-ALE 10 µm; distance AME-AME 10 µm; diameter AME 25 µm. Leg 1: 2.04 (0.60 + 0.14 + 0.56 + 0.46 + 0.28), tibia 2: 0.44, tibia 3: 0.38, tibia 4: 0.60; tibia 1 L/d: 10; diameters of leg femora 90 µm, of leg tibiae 55 µm.

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

BODY. Habitus as in Fig. 3E. Ocular area barely raised. Carapace without thoracic groove (cf. Fig. 24A). Clypeus unmodified but with sclerotized rim. Sternum slightly wider than long (0.33/0.27), with pair of very low anterior processes near coxae 1 (Fig. 24B). Abdomen oval to globular. Gonopore without epiandrous spigots (Fig. 24E). Spinnerets as in congeners (Fig. 24G).

CHELICERAE. As in Fig. 22H–J; with pair of long frontal apophyses close together; stridulatory files poorly visible in dissecting microscope, consisting of approximately 15 ridges (Fig. 24C), distances between ridges ~3.2 µm.

PALPS. As in Figs 21, 25A–D; coxa unmodified; trochanter ventrally slightly protruding; femur proximally with retrolateral rounded process followed distally by depression, with prolateral stridulatory pick, distally strongly 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 prolateral side; tarsus with strong dorsal hairs; tarsal organ capsulate (Fig. 25E). Procursus (Fig. 22A–C) small, distally semitransparent and curved towards dorsal and prolateral; with strong macroseta originating on retrolateral side; genital bulb (Fig. 22D–G) complex, with flat ventral process, and dorsal process consisting of sclerite set with small teeth (Fig. 25F), membranous elements (putative embolus), and prolateral sclerite.

LEGS. Without spines, without curved hairs; with many short vertical hairs in several rows on tibiae 1 and 2 (Fig. 26C; barely visible in dissecting microscope): ~25–30 hairs in each row on tibia 1 and ~10 hairs in each row on tibia 2; retrolateral trichobothrium of tibia 1 at 63%; prolateral trichobothrium absent on tibia 1; thin metatarsal hairs present on metatarsi 3 (one hair) and 4 (three hairs), in proximal ventral position (cf. Fig. 26E); tarsus 1 with ~5 pseudosegments, barely visible in dissecting microscope; tarsal organ on leg 4 apparently non-functional (cf. Fig. 27D). Chemosensory hairs, trichobothria, other tarsal organs, rimmed pores, cuticular plates, and tarsal claws as in congeners (Figs 26, 27).

Variation (male)

Tibia 1 in eight males (incl. holotype): 0.54–0.62 (mean 0.57). In male from between Al Rawda and Al Hayema, prolateral sclerite of genital bulb (arrow in Fig. 22D) straight rather than curved towards ventral, and cheliceral apophyses slightly shorter. Genetic distances between sequenced specimen from this locality and putative conspecifics from other localities were barely higher than those among specimens from the other localities (see below).

Female

In general very similar to male but clypeus rim not sclerotized, sternum unmodified, chelicerae without stridulatory files (Fig. 24D), leg tibiae without short vertical hairs. Tibia 1 in nine females: 0.54–0.68 (mean 0.60). Palp ends distally in simple sclerotized tip (Fig. 26A). Epigynum (Figs 23, 24F) anterior plate trapezoidal, without pocket but with anterior ridge, with pair of posterior dark marks, posterior margin almost straight; posterior plate wide and short. Internal genitalia (Figs 23, 34C) with pair of transversal sclerites and pair of large membranous elements, apparently without pore plates. Females from between Al Rawda and Al Hayema with smaller dark marks at posterior margin of epigynal plate.

Intraspecific distances. The genetic (K2P) distances between four sequenced specimens ranged from 5–7% (Table 2). The morphologically slightly deviant specimens from between Al Rawda and Al Hayema differed from specimens of the other three localities by 6–7%; differences among specimens of the other three localities ranged from 5–6%.

Distribution. Known from several localities in eastern Oman (Fig. 4B).

Natural history. The spiders were found by turning rocks in habitats fully exposed to the sun (Fig. 5E, F). Upon turning the stones, the spiders ran rapidly and dropped to the ground. They shared the habitat with two further Pholcidae species: Artema bahla Huber, 2019 and Crossopriza miskin Huber, 2022 .