Hexurella rupicola Gertsch & Platnick, 1979

Monjaraz-Ruedas, Rodrigo, Mendez, Raymond Wyatt & Hedin, Marshal, 2023, Species delimitation, biogeography, and natural history of dwarf funnel web spiders (Mygalomorphae, Hexurellidae, Hexurella) from the United States / Mexico borderlands, ZooKeys 1167, pp. 109-157 : 109

Hexurella rupicola Gertsch & Platnick, 1979

Fig. 13

Hexurella rupicola Gertsch & Platnick (1979): 31, figs 4, 32, 82, 89-91 (Dmf).

Hexurella rupicola Platnick & Forster (1982): 8, fig. 22.

Hexurella rupicola Hedin et al 2019: figs 1, 3, 4, 5, 6.

Material examined.

Near-type locality material: USA - California, Riverside Co. • ♂, 1 imm; west of Temecula , Rancho California Rd , 33.4973, -117.1694; 22 Dec. 2021; M. Hedin, R. Monjaraz-Ruedas, G. Azevedo leg.; MCH 21_107; Non-type material : - California, San Diego Co. • ♂; 1.3 mi W of Guatay, Old Hwy 80, N side Guatay Mtn , 32.8541, -116.5754; 26 Jan. 2002; M. Hedin leg.; MCH 02_029; - San Diego Co. • ♀, 1 imm; 1.3 mi W of Guatay, Old Hwy 80, N side Guatay Mtn, 32.8541, -116.5754; 24 Mar. 2002; M. Hedin leg.; MCH 02_045; • ♂, 1 imm; 1.3 mi W of Guatay, Old Hwy 80, N side Guatay Mountain , 32.8541, -116.5754; 29 Feb. 2004; M. Hedin leg.; MCH 04_002; • ♀; 1.3 mi W of Guatay, Old Hwy 80, N side Guatay Mountain , 32.8541, -116.5754; 28 Jan. 2006; M. Hedin leg.; MCH 06_010; - San Diego Co. • ♂, 2 imm; south side of Viejas Mtn, off I-8 at Williams Rd, 32.8357, -116.7319; 19 Dec. 2021; M. Hedin leg.; MCH 21_105; - San Diego Co. • 2♀, 1 imm; near Viejas Mountain trailhead, off Boundary Truck Trail, 32.8550, -116.7400; 11 Mar. 2022; R.W. Mendez leg.; RWM 22_061.- San Diego Co. • 2♂, 6♀, 5 imm; San Ysidro Mtns, NW Lupe Spring, off Cottonwood Creek road, 32.5906, -116.7738; 10 Mar. 2022; R.W. Mendez leg.; RWM 22_058 .

Diagnosis.

Following the original diagnosis of Gertsch and Platnick (1979), H. rupicola is similar to H. encina in that the prolateral surface of male femur I lacks spines (Fig. 13A ), distinguishing these two taxa from all other western clade members. Hexurella rupicola differs from H. encina in also lacking the distinctive femur I ventral spines found in this latter taxon ( Gertsch and Platnick 1979: fig. 86). These authors also note that H. rupicola and H. encina differ in the separation of the embolus from the conductor, being separated versus closely appressed, respectively ( Gertsch and Platnick 1979: figs 87 vs. 90).

Variation.

We have examined adult males from three locations in San Diego County (near Guatay, Viejas Mtn, San Ysidro Mtns), south of the type locality in Riverside County. Males from all locations are similar in condition, lacking spines on the prolateral surface of femur I (Fig. 13A ).

Distribution and natural history.

Known from inland chaparral in Riverside and San Diego Counties. Temecula specimens were uncommonly found under stones in north facing Adenostoma fasciculatum Hook & Arn. (Chamise) chaparral, while Viejas Mountain specimens were found to be common under well-set intrusive igneous rocks in more exposed, south-facing Chamise chaparral (Fig. 13D, F ). The Guatay Mountain collections are north-facing and from slightly higher elevations, with a richer plant community ( Quercus sp., A. fasciculatum , Arctostaphylos sp., etc.) but again with intrusive igneous rocks prevailing. Like other western Hexurella , H. rupicola must deal with long periods of hot and dry conditions in the summer.

Discussion.

The gap between H. rupicola and the Mojave species requires further sampling. We however note that many devoted mygalomorph biologists have sampled for decades in this region (e.g., Wendell Icenogle in Riverside County) without detecting Hexurella .

Conservation status.

Likely secure, and likely with a slightly larger distribution than is currently known.

Figures

Figure 13. H. rupicola A ♂ leg I, prolateral view (SDSU _ TAC 000682, San Ysidro Mtns) B ♂ palp, retrolateral view (SDSU _ TAC 000682, San Ysidro Mtns) C live ♂ in web (San Ysidro Mtns, RWM 22 _ 058) D live ♂ in situ (Viejas Mtn, MCH 21 _ 105), E ♀ spermathecae (SDSU _ TAC 000683, San Ysidro Mtns) F Viejas Mtn (MCH 21 _ 105) microhabitat.