Ixchela placida (Gertsch, 1971)

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 : 300-302

Ixchela placida (Gertsch, 1971)

Figures 60–71

Coryssocnemis placidus Gertsch, 1971: 57 , figs 28–29 (description Ƥ). Coryssocnemis placida Brignoli, 1983: 161 .

Ixchela placida Huber, 2000: 153 (Ƥ transfer from Coryssocnemis ).

Type data: MEXICO: Veracruz: 1 Ƥ holotype (AMNH) (not examined) [8 August 1967; J. Reddell] from Cueva de Ojo de Agua de Tlilapan (lat 18.8065°, lon -97.1014°, 1176 m), Municipio Tlilapan.

Material examined. MEXICO: Veracruz: 1 Ƥ, 3 immatures (AMNH) [5 January 1974; W. Elliott] from Sotano del Hombre Invisible, Soledad Atzompa (lat 18.7545°, lon -97.1515°, 2109 m), Municipio Soledad Atzompa. 1 3, 1 immature (AMNH) [5 January 1974; J. Reddell, W. Elliott, R. Jameson, D. McKenzie] from Cueva de Mazatopa, Soledad Atzompa (lat 18.7545°, lon -97.1515°; 2109 m), Municipio Soledad Atzompa. 1 immature (AMNH) [June 1963; D. McKenzie] from Sotano del Oztauatlilztaloa, 0.5 km NW of Tequila (lat 18.7324°, lon -97.0734°; 1705 m), Municipio Tequila. 1 immature (AMNH) [6 August 1967; J. Reddell, T. Evans] from Sotano de Sphodrini , Tequila (lat 18.7295°, lon -97.0710°; 1679 m), Municipio Tequila. 2 immatures (AMNH) [6 August 1967; J. Reddell, J. Fish, T. Evans] from Rock Quarry, 10.5 km on Tequila-Zongolica Road (lat 18.6823°, lon -97.0561°, 1920 m). 1 immature (AMNH) [5 August 1967; J. Reddell, T. Evans] from Cueva de Opilionida, 1.6 km N of Tequila (lat 18.7438°, lon -97.0693°; 1860 m). 4 ƤƤ (2 with egg sac) (CNAN 3348-3351) [22 January 2010; A. Valdez, O. Francke, C. Santibáñez, J. Cruz] from Cueva de Atlahuilapa (lat 18.7037°, lon - 97.0855°; 1142 m) (oak-pine forest), Municipio Atlahuilco. 5 3, 9 ƤƤ, 5 immatures (CNAN 3352) (same anterior data). 1 3, 1 Ƥ (CNAN 3353) [13 May 2011; O. Francke, J. Cruz, I. Bokma, G. Contreras] (same anterior locality). 1 Ƥ (TMM-UT Inv. Zoo. Coll. # 10,326) [25 March 1995; P. Sprouse] from Cueva de Xometla, 800 m E of Atlahuilco, Municipio Atlahuilco. Puebla: 1 3, 1 Ƥ (AMNH) [January 1978; P. S. Strickland] from Zoquitlán, 2nd River Cave (lat 18.3362°, lon -97.0201°; 2220 m), Municipio Zoquitlán. 1 3, 1 Ƥ (AMNH) [January 1977; P. Strickland, P. Forsythe, F. Poer, J. Rodemarker] from Sotano of Log-Filled Sink, Zoquitlán, Municipio Zoquitlán.

Diagnosis. Close relative of I. abernathyi , distinguished by FAC slightly curved apically ( Figs 62, 63 ); by palp femur slightly curved in dorsal-distal part ( Figs 65, 66 ); by PAB curved and thinner, forming a notch between PAB and embolus ( Fig. 66 ); by opisthosoma less conical ( Fig. 60 ); by a wide brown region longitudinal on clypeus ( Fig. 64 ), absent on I. abernathyi ( Fig. 23 ); by having a single darker sub-distal ring on the femora, I. abernathyi has numerous rings along femora and tibiae; and by epigynum with two lateral prominent corners ( Figs 68, 69, 71 ); in frontal view, with distal margin concave ( Fig. 68 ).

Description. Male. (CNAN 3352). Prosoma: Carapace beige; ocular region brownish, with small pale brown region behind PME ( Fig. 61 ); a wide dark brown region around the fovea ( Fig. 61 ); and with lateral spots fused, forming two longitudinal brown blotches ( Fig. 61 ). Clypeus with a wide longitudinal brown region ( Fig. 64 ). Chelicerae brown, with SAC ( Fig. 62 ). Sternum and endites dark brown ( Fig. 60 ). Labium darker brown than sternum, distally pale. Endites distally pale. Legs: Coxae pale yellow, small brown region in prolateral and retrolateral parts. Trochanters brown. Femora dark brown, paler basally becoming orange; without numerous rings, only a wide sub-distal gray ring. Patellae dark gray. Tibiae, metatarsi and tarsi brown, paler than femora; tibiae with one gray basal ring and another one distally. Opisthosoma: Semi conical, slightly larger than high, with dark blue coloration ( Fig. 60 ). Gonopore plate oval. Palp: Femur with small VAF ( Fig. 65 ). Procursus long, sigmoidal, with small and curved distal spine ( Figs 65, 67 ). Embolus distally with dorsal spine-shaped projection; ventrally with apical projection, thin and curved ( Figs 65, 66 ). Measurements: Total length 7.30. Carapace 2.90 long, 2.85 wide. Clypeus 1.15 long. Diameter AME 0.14, ALE 0.26, PME 0.19, PLE 0.24. Distance ALE-PME 0.18, PME- PME 0.34. Leg I 56.0 (15.50+1.23+14.25+19.62+5.40), tibia II: 10.87, tibia III: 8.85, tibia IV: 10.87. Tibia I l/d: 29.12.

Female. (CNAN 3352). Similar to the male, differences: Legs: Femore with wide gray sub distal ring, darker than the male. Patellae darker gray than on the male. Tibiae with basal and distal gray rings darker than on the male. Epigynum: Wider than long and high ( Figs 68, 69 ). PP with lateral concavity; MSE thin, with Y-shaped upside down ( Fig. 70 ). Long concavities between MSE and PP ( Fig. 70 ). Measurements: Total length 8.70. Carapace 3.50 long, 3.20 wide. Clypeus 1.35 long. Diameter AME 0.14, ALE 0.30, PME 0.23, PLE 0.28. Distance ALE-PME 0.23. PME-PME 0.33. Leg I: 63.17 (16.37+1.50+16.00+23.00+6.30), tibia II: 12.00, tibia III: 9.50, tibia IV: 11.75; tibia I l/d 31.75.

Variation. The ophistosoma on some males and females is blue and on others is green in life. There is minor variation in the total length in males, but among the females there is a marked continuous variation. Male tibia I: 14.25–16.25 (x = 14.97). Female tibia I: 10.00–17.00 (x = 14.15).

Natural History. The specimens from Cueva de Atlahuilapa were collected on their sheet webs 5–8 m inside the cave, primarily close to the walls ( Fig. 2 ). The specimens were collected relatively close to each other. The cave had high humidity, ca 80%, and was fairly cold, because of a small river inside. The cave is located in a large karstic zone, in oak-pine forest at 1142 m elevation.

Distribution. MEXICO: Veracruz (Gertsch 1971), Puebla ( Fig. 85 ).

Figures

FIGURE 85. Known distribution of Ixchela abernathyi (Gertsch, 1971), Ixchela furcula (F. O. Pickard-Cambridge, 1902), Ixchela pecki (Gertsch, 1971), Ixchela placida (Gertsch, 1971) and Ixchela simoni (O. Pickard-Cambridge, 1898).

FIGURES 60 – 71. Ixchela placida (Gertsch, 1971). Male: 60, Habitus, lateral view. 61, Carapace, dorsal view. 62, Chelicerae, frontal view. 63, Chelicera, lateral view. 64, Carapace, frontal view. 65 – 66, Left palp, retrolateral and prolateral views respectively. 67, Bulb and procursus, dorsal view. Female: 68, Epigynum, frontal view. 69, Epigynum, ventral view. 70, Epigynum, dorsal view (arrow indicates the sac-shaped concavities between MSE and PP). 71, Epigynum, left lateral view. Scales: 1 mm (Figs 60, 61, 64, 65, 66, 68 – 71), 0.5 mm (Figs 62, 63, 67).

FIGURES 19 – 30. Ixchela abernathyi (Gertsch, 1971). Male: 19, Habitus, lateral view. 20, Carapace, dorsal view. 21, Chelicerae, frontal view. 22, Chelicerae, lateral view. 23, Carapace, frontal view. 24, Bulb and procursus, dorsal view. 25 – 26, Left palp, retrolateral and prolateral views respectively (arrows indicate the apical-dorsal projection spine-shaped on the embolus, and the apical-vental projection respectively). Female: 27, Epigynum, frontal view. 28, Epigynum, ventral view. 29, Epigynum, dorsal view. 30, Epigynum, left lateral view. Scales: 1 mm (Figs 19, 21, 23, 25, 26), 0.5 mm (Figs 20, 22, 24, 27 – 30).

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.