Ixchela tzotzil, Valdez-Mondragón, Alejandro, 2013

Valdez-Mondragón, Alejandro, 2013, Taxonomic revision of the spider genus Ixchela Huber, 2000 (Araneae: Pholcidae), with description of ten new species from Mexico and Central America, Zootaxa 3608 (5), pp. 285-327 : 316-318

Ixchela tzotzil new species

Figures 160–172

Type data. MEXICO: Chiapas: 1 3 holotype (CNAN T0728) [17 June 2011; A. Valdez, O. Francke, C. Santibáñez, J. Cruz, R. Monjaraz, G. Contreras, K. Zárate] from Grutas de Arcotete (lat 16.7254°, lon -92.5846°; 2323 m), Municipio San Cristóbal de las Casas. Paratypes: 1 Ƥ (with ovisac) (CNAN T0729) [31 July 2010; D. Barrales, K. Zárate], same locality as holotype. 4 3, 3 ƤƤ (CNAN T0730), same data as holotype.

Other material examined. MEXICO: Chiapas: 4 3, 3 ƤƤ, 3 immatures (CNAN 3326) [31 July 2010; D. Barrales, K. Zárate], same locality as holotype. 2 3, 1 Ƥ, 18 immatures (CNAN 3327), same data as holotype. 1 3, 21 immatures (CNAN 3548) [10 June 2010; K. Zárate, C. Pérez, E. Pérez], same locality as holotype. 1 Ƥ (AMNH) [24 August 1966; J. Ivie, W. Ivie] from 8 km W of San Cristóbal de las Casas (lat 16.733329°, lon - 92.714494°; 2420 m), Municipio San Cristóbal de las Casas.

Etymology. The specific name is a noun in apposition and refers to the main ethnic group: Los Tzotziles; that live in the Municipio San Cristóbal de las Casas, where the type locality is located.

Diagnosis. Resembles to I. abernathyi , distinguished by the chelicerae with FAC bigger ( Figs 162, 163 ); by the SAC inconspicuous ( Fig. 162 ); and by the epigynum with central apex wider in frontal view ( Fig. 169 ), and by the trapezoidal shape in ventral view ( Fig. 170 ).

Description. Male (Holotype). Prosoma: Pale yellow, with three brown spots each side ( Fig. 161 ). Ocular region orange, with a wide brown line in the middle ( Fig. 161 ). Fovea with a wide brown region surrounding it and extending backward ( Fig. 161 ). Clypeus pale orange, with a wide longitudinal grey region ( Fig. 164 ). Chelicerae brown ( Figs 162, 163 ). Sternum orange, with several small grey spots, particulary at the base of the setae. Labium and endites brown, pale distally. Endites with retrolateral apophysis slightly bifurcated. Legs: Coxae pale yellow, trochanters brown. Femora dark orange, with several brown rings throughout its length; one sub-distal ring, wide and very marked. Patellae brown. Tibiae orange with several brown rings throughout its length, less marked than on femora ( Fig. 12 ). Metatarsi and tarsi orange, without rings. Opisthosoma: Conical, larger than high, pale grey ( Fig. 160 ). Gonopore plate hexagonal. Palp: Femur conical, pale orange, paler ventrally, with VAF conical ( Fig. 167 ). Patellae and tibia orange. Procursus brown, paler basally, long and slightly curved, with distal spine small and curved ( Fig. 167 ). VPP inconspicuous, with few and large setae ( Fig. 167 ). Embolus conical, dorsally with bifurcated spine (arrow Fig. 166 ); ventrally with apical large projection ( Figs 166–168 ). PAB wide ( Fig. 168 ). Measurements: Total length 7.20. Carapace 2.90 long, 2.65 wide. Clypeus 1.10 long. Diameter AME 0.13, ALE 0.22, PME 0.18, PLE 0.24. Distance ALE-PME 0.16, PME-PME 0.25. Leg I: 49.45 (13.31+1.20+13.37+16.87+4.70), tibia II: 9.50, tibia III: 8.60, tibia IV: 11.25. Tibia I l/d: 30.42.

Female (Paratype). (CNAN T0729). Similar to the male, differences: Prosoma: Paler yellow than on male. Ocular region orange, paler than on male, with one thin line from each posterior eye toward posterior region. Brown longitudinal pattern on the clypeus. Legs: Femora, tibiae, metatarsi and tarsi paler orange than the male. Epigynum: Wider than long ( Figs 170, 172 ). PP wide, with two oval concavities sac-shaped between MSE and PP, MSE with upside down Y-shape ( Fig. 171 ). Measurements: Total length 7.50. Carapace 2.70 long, 2.60 wide. Clypeus 1.00 long. Diameter AME 0.14, ALE 0.20, PME 0.18, PLE 0.22. Distance ALE-PME 0.19. PME-PME 0.25. Leg I: missing, tibia II: 9.00, tibia III: 6.60, tibia IV: 8.50; tibia I l/d missing.

Variation. Males and females with variation in the color of dorsal spots on carapace and on the region around the fovea, in some specimens darker brown than on others. There is variation in the number of rings on the legs in both sexes, 5–9 rings on femora and 4–8 on tibia, femur I has more rings than the others. Male tibia I: 9.75–13.37 (x = 11.37). Female tibia I: 8.70–8.80 (x = 8.75).

Natural History. Most specimens were collected inside the cave on their irregular sheet webs, in cracks between walls or between karstic formations (stalactites, stalagmites and columns). Some specimens were collected outside the cave, in an oak-pine forest, under fallen logs and boulders ( Fig. 12 ). Ixchela tzotzil new species was collected around the type locality of I. pecki, Grutas de Arcotete, Chiapas; although specimens of I. pecki were not collected at this locality during this study, the two species might be considered sympatric. Ixchela pecki was collected 30 km SE of Grutas de Arcotete, inside the Cueva de Teopisca, Chiapas. Both species are easily distinguished morphologically ( Figs 47–59 , 160–172 ), as well as by molecular data (in prep.).

Distribution. MEXICO: Chiapas ( Fig. 214 ).

Figures

FIGURE 214. Known distribution of Ixchela franckei new species, Ixchela huasteca new species, Ixchela santibanezi new species, Ixchela tzotzil new species and Ixchela viquezi new species.

FIGURES 160 – 172. Ixchela tzotzil new species. Male: 160, Habitus, lateral view. 161, Carapace, dorsal view. 162, Chelicerae, frontal view. 163, Chelicera, lateral view. 164, Carapace, frontal view. 165, Bulb and procursus, dorsal view. 166, Embolus, prolaterodorsal view (arrow indicates the bifurcated spine). 167 – 168, Left palp, retrolateral and prolateral views respectively. Female: 169, Epigynum, frontal view. 170, Epigynum, ventral view. 171, Epigynum, dorsal view. 172, Epigynum, left lateral view. Scales: 1 mm (Figs 160, 161, 164, 167, 168, 172), 0.5 mm (Figs 162, 163, 165, 169 – 171), 0.25 mm (Fig. 166).

FIGURES 1 – 12. Living specimens of the genus Ixchela Huber, 2000, from Mexico. 1, Ixchela abernathyi (Gertsch, 1971), female from Km 227 Carretera Federal No. 70 Cd. San Luis Potosí-Rio Verde, San Luis Potosí. 2, Ixchela placida (Gertsch, 1971), female from Cueva de Atlahuilapa, Veracruz. 3, Ixchela pecki (Gertsch, 1971), female from Cueva de Teopisca, Chiapas. 4, Ixchela simoni (O. Pickard-Cambridge, 1898) from 2 km W of crossroad Omiltemi-Chautipan, Guerrero. 5, Ixchela mixe new species, female with egg sac from cave near Tlahuitoltepec, Oaxaca. 6, Ixchela huberi new species, male from Santa Inés del Monte, Oaxaca. 7, Ixchela juarezi new species, female with egg sac from 2 km E of Guelatao, Oaxaca. 8, Ixchela taxco new species, female from Rancho La Soñadora, 6 km W of Taxco, Guerrero. 9, Ixchela franckei new species, male from Cueva del Borrego, 3.5 km E of Omiltemi, Guerrero. 10 – 11, Ixchela huasteca new species: 10, male from 1.5 km road to Microondas La Pingüica, Querétaro; 11, female with egg sac from Buenavista, near Ahuacatlan, San Luis Potosí. 12, Ixchela tzotzil new species, male from Grutas de Arcotete, Chiapas.

FIGURES 47 – 59. Ixchela pecki (Gertsch, 1971). Male: 47, Habitus, lateral view. 48, Carapace, dorsal view. 49, Chelicerae, frontal view. 50, Chelicera, lateral view. 51, Carapace, frontal view. 52, Bulb and procursus, dorsal view (arrow indicates the dorsal sclerotized line on embolus). 53 – 54, Left palp, retrolateral and prolateral views respectively (arrows in Fig. 53 indicate the dorsal sclerotized line (left arrow), and ventral sclerotized line on embolus (right arrow )). 55, Left embolus, prolateraldorsal view (arrow indicates the sclerotized spine small and sub-distal on the embolus). Female: 56, Epigynum, ventral view. 57, Epigynum, dorsal view (arrow indicates the sac-shaped concavities between MSE and PP). 58, Epigynum, frontal view. 59, Epigynum, left lateral view. Scales: 1 mm (Figs 47, 48, 51, 53, 54), 0.5 mm (Figs 49, 50, 52, 55 – 59).