Nesticus barrowsi 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 barrowsi Gertsch, 1984

Figs 44A, B , 45A-H

Nesticus barrowsi Gertsch, 1984: 35, figs 103-105, 118-120; Reeves 2000: 338.

Material examined.

Type material: Holotype: USA - Tennessee, Blount Co. • ♂ holotype; Tuckaleechee Caverns, Tuckaleechee Cove; 1 Nov. 1938; W.B. Jones leg.; AMNH. New collections from type locality: - Blount Co. • ♀; Tuckaleechee Caverns, Tuckaleechee Cove; 22 Sep. 1992; M. Hedin, S. O’Kane leg. Non type material: - Blount Co. • ♂, 7♀; Great Smoky Mountains NP, Gregory Cave , Cades Cove; 21 Aug. 1992; M. Hedin leg.; • 2♀; Great Smoky Mountains NP, Rich Mountain Blowhole , Calf Cave ; 2 Aug. 2000; M. Hedin, J. Cokendolpher, W. Reeves leg.; MCH 00_147; • ♀; Great Smoky Mountains NP, White Oak Sinks, Rainbow Cave ; 21 Aug. 1992; M. Hedin leg.

Diagnosis.

The diagnosis of Gertsch (1984) is revised here to recognize the phylogenetic affinities within the Nesticus barrowsi group. Nesticus barrowsi is troglomorphic (long-legged, pale, approximately eyeless, relatively large-bodied), unlike other species in the species group. The male tegular apophysis curves to lie behind a quadrate median apophysis, is sharply tipped, without a basal keel. The paracymbial dorsal process is translucent, skinny and finger-like, while the distal process includes a well-sclerotized pointed tip and a small ventral keel (Fig. 44A, B ). Female N. barrowsi differ from other members of the species group in overall morphology of the epigynum, including the pear-shaped spermathecae (Fig. 45A-H ).

Variation.

Minor variation is observed in the height and width of the paired epigynal plates across geographic locations (Fig. 45A-H ).

Distribution and natural history.

This troglomorphic species is only known from caves in karst windows along the northwestern edge of Great Smoky Mountains National Park (Cades Cove, Tuckaleechee Cove; Fig. 42 ). Reeves (2000) reported Nesticus barrowsi in sympatry with N. stupkai at two cave locations in Great Smoky Mountains National Park. We also collected these species in near syntopy at White Oak Sinks, with N. barrowsi found in the dark zone of caves and N. stupkai found closer to cave entrances (twilight zone).

Figures

Figure 42. Distribution of the Nesticus barrowsi group. Type localities designated with yellow circles. State boundaries and major cities shown for geographic context. Dashed lines circumscribe known species distributions.

Figure 44. Nesticus barrowsi ♂ palps. Tennessee, Blount Co., Great Smoky Mountains NP, Gregory Cave, MCH specimen # 1295, ventral (A), dorsal (B). Scale bar: 0.5 mm.

Figure 45. Nesticus barrowsi epigynal variation. Tennessee, Blount Co., Great Smoky Mountains NP, Calf Cave, MCH 00 _ 147, ventral (A), dorsal (B). Tennessee, Blount Co., Great Smoky Mountains NP, White Oak Sinks, Rainbow Cave, MCH specimen # 1303, ventral (C), dorsal (D). Tennessee, Blount Co., Tuckaleechee Caverns, MCH specimen # 1568, ventral (E), dorsal (F). Tennessee, Blount Co., Great Smoky Mountains NP, Gregory Cave, MCH specimen # 1297, ventral (G), dorsal (H). Scale bar: 0.5 mm.