Psilochorus texanus, Slowik, Jozef, 2009

Slowik, Jozef, 2009, A review of the cellar spider genus Psilochorus Simon 1893 in America north of Mexico (Araneae: Pholcidae), Zootaxa 2144, pp. 1-53 : 41-43

Psilochorus texanus new species

Figs. 158–166, 190

Types. ɗ holotype and three Ψ paratypes from Padre Island, seashore park (27.30 N, 97.16 W), Kennedy County, Texas, USA; coll: J & W Ivie, 19-Jul-1966, AMNH.

PLATE 19. Figures 158–166. Psilochorus texanus new species. 158–162. Male holotype 158. Dorsal view of chelicerae. 159. Lateral view of chelicera. 160. Dorsal view of bulb apophysis. 161. Lateral view of procursus. 162. Lateral view of cleared procursus. 163–166. Epigynum of paratype. 163. Anterior view. 164. Ventral view. 164. Posterior view. 166. Lateral view.

PLATE 20. Figures 167–175. Psilochorus topanga Chamberlin and Ivie. 167–171. Male paratype. 167. Dorsal view of chelicerae. 168. Lateral view of chelicera. 169. Dorsal view of bulb apophysis. 170. Lateral view of procursus. 171. Lateral view of cleared procursus. 172–175. Epigynum of female paratype. 172. Anterior view. 173. Ventral view. 174. Posterior view. 175. Lateral view.

Further paratypes. 1 ɗ, 5 Ψ; MEXICO, Tamaulipas, 1 Ψ, Mier, Tamaulipas, L I Davis, 24-Oct-1937, AMNH; USA, Texas, Hidalgo County, 1 Ψ, Edinburg TX, S Mulaik, 07-Nov-1934, AMNH.

Etymology. The specific epithet refers to the state of the type locality.

Diagnosis. Specimens may be distinguished by: males spur rounded and curved in dorsal view (Fig. 158), long procursus with a squared end (Fig. 161), procursus appears bifurcate when cleared (Fig. 162) no AEP, MEP and PEP without ridges (Figs. 163, 165).

Male: (Holotype) (Figs. 158–162) Total length: 2.00; carapace length: 0.84; carapace width: 0.82; leg 1: 12.10 (3.68 + 0.32 + 3.71 + 3.40 + 0.99); tibia 2: 3.91; tibia 3: 2.17; tibia 4: 3.08. 17 leg I tarsal segments; femur1/carapace length: 4.38; RT at 16.2%; DT at 10.5%. Color typical for the genus. Spur large, located on the proximal part of the chelicerae (Fig. 159), curving ventrally in dorsal view, ends rounded (Fig. 158). Procursus distal area swollen, angular, end square to slightly concave (Fig. 161). Bulb apophysis bifurcate, prolateral tip 3 to 4 times as long as retrolateral, both tips pointed. Retrolateral tap extending to 1/3 the length of the prolateral tip, enclosing the retrolateral tip (Fig. 160).

Female: (N=3) Total length: 2.47± 0.19; carapace length: 1.00 ± 0.06; carapace width: 0.84± 0.02; leg 1: 10.25 ± 0.28 (2.65 ± 0.06 + 0.39 ± 0.00 + 2.92 ± 0.10 + 3.38 ± 0.11 + 0.91 ± 0.03); tibia 2: 2.08 ± 0.10; tibia 3: 1.69± 0.11; tibia 4: 2.28 ± 0.08. 17 leg I tarsal segments; femur1/carapace length: 2.65 ± 0.01; RT at 16.1–18.2%; DT at 10.0–13.9%. Color typical for the genus. No AEP, MEP low, rounded (Fig. 163), two dark areas located along the anterior mesal edge (Fig. 163). PEP rounded, following the shape of the MEP (Fig. 165).

Remarks. Males of P. t e x a n u s may be confused with P. re d e m p t u s in which it shares it’s small size. The procursus of P. texanus is long and narrow (L/W>9) and lacks the dorsal step. The female may be confused with P. coloradensis and P. simoni in which it differs in the lack of an AEP and any lateral markings on the MEP.

Distribution. Southern Texas south into Mexico.