Nesticus archeri Gertsch, 1984

Hedin, Marshal & Milne, Marc A., 2023, New species in old mountains: integrative taxonomy reveals ten new species and extensive short-range endemism in Nesticus spiders (Araneae, Nesticidae) from the southern Appalachian Mountains, ZooKeys 1145, pp. 1-130 : 1

Nesticus archeri Gertsch, 1984

Fig. 10A-C

Nesticus archeri Gertsch, 1984: 32, figs 115-117, 129-131.

Material examined.

Type material: Holotype: USA - Alabama • 1♂; Mt. Cheaha, Cheaha State Park ; 21 Apr. 1947; A.F. Archer leg; AMNH. Non type material: USA - Alabama , Clay Co. • 2♂, 3♀; Cheaha State Park , 0.5 mi N Hernandez Peak, along Pinhoti Trail ; 33.4645°N, - 85.8113°W; 26 Mar. 1995; M. Hedin, B. Dellinger leg.; • 2♂, 2♀; Cheaha State Park , N side of McDill Point; 33.4547°N, - 85.8205°W; 26 Mar. 1995; M. Hedin, B. Dellinger leg.; • 2♂, 4♀; Cheaha State Park , Pinhoti Trail, 0.5 mi. S Hernandez Peak; 33.4537°N, - 85.8144°W; 26 Mar. 1995; M. Hedin, B. Dellinger leg.; • ♂, 3♀; Talladega Mountain , Cheaha Wilderness, Nubbin Creek Trail, vicinity Mill Shoal Creek ; 33.4269°N, - 85.8177°W; 26 Mar. 1995; M. Hedin, B. Dellinger leg.; • ♂, 3♀; Talladega Mountain , Talladega National Forest , near headwaters of Cave Creek ; 33.4344°N, - 85.8128°W; 26 Mar. 1995; M. Hedin, B. Dellinger leg.; - Cleburne Co. • 1 imm; Cheaha State Park , just north of Bald Rock ; 33.4966°N, - 85.8075°W; 27 Sep. 1991; M. Hedin, K. Crandall leg.; • 4♂, 13♀; Cheaha State Park , just north of Bald Rock ; 33.4966°N, - 85.8075°W; 24 Sep. 1992; M. Hedin, S. O’Kane leg.; • 2♂, 2♀; Cheaha State Park , vicinity Bald Rock saddle, 0.5 mi NE Bald Rock; 33.4985°N, - 85.8028°W; 25 Mar. 1995; M. Hedin, B. Dellinger leg.

Diagnosis.

The only Nesticus species with a surface-dwelling habitus (small-bodied, darkly pigmented, well-developed eyes) in the region, and the only known Nesticus from Talladega Mountain. Male palp with a forked tegular apophysis, distal (highly sclerotized) fork lying behind pointed basal part of median apophysis in ventral view (Fig. 10A .). Paracymbium also distinctive, with prominent, sclerotized paradistal process. Very distinctive truncate, heart-shaped epigynum with a narrow median septum, large lateral pockets, and elongate spermathecae that hug the outer edges of the epigynal pockets, curving inwards anteriorly (Fig. 10B, C ).

Variation.

No significant male or female genitalic variation was noted in the material examined.

Distribution and natural history.

All known records are from high elevation habitats (most above 600 m, but as low as 430 m) on Talladega Mountain, east-central Alabama (Fig. 8 ). This species was previously known only from type material collected at an unspecified location within Cheaha State Park, at the northern end of Talladega Mountain. New collections suggest that Nesticus archeri can be found at several places on Talladega Mountain, spanning an approximately 102 kilometer area from near Bald Rock (northern side of Cheaha Mountain) in the north to Mill Shoal Creek in the south.

This species has been collected in dark, cool, relatively moist near-surface habitats. For example, field notes from 1992 collections north of Bald Rock indicate that spiders were collected from "below bluffs on a steep hillside", in "talus with a heavy leaf litter cover", where spiders were "most abundant under large rocks close to the surface". This situation compares favorably with the original "heavy talus of ravine" collections made by A.F. Archer, and the 1995 Hedin and Dellinger collections, most of which were made in north-facing talus, although at least one collection was from southwest-facing talus. This species is perhaps not as uncommon as previously believed and (in the late 1990s) was found consistently in suitable microhabitats.

Remarks.

We view Gertsch’s drawing of the male conductor (fig. 129) as inaccurate (compare to Fig. 10A ).

Figures

Figure 8. Distribution of the Nesticus archeri group, including Nesticus archeri, N. pecki, N. jemisinae, N. cressleri, and N. stygius. State boundaries and major cities shown for geographic context. Dashed lines circumscribe the distributions of N. pecki and N. stygius.

Figure 10. Nesticus archeri A Alabama, Clay Co., vicinity Mill Shoal Creek, ♂ specimen MCH # 2132, ventral palp B Alabama, Clay Co., vicinity Mill Shoal Creek, ♀ specimen MCH # 2129, epigynum, ventral view C dorsal view. Scale bar: 0.5 mm.