Ixchela azteca, Valdez-Mondragón & Francke, 2015

Valdez-Mondragón, Alejandro & Francke, Oscar F., 2015, Phylogeny of the spider genus Ixchela Huber, 2000 (Araneae: Pholcidae) based on morphological and molecular evidence (CO 1 and 16 S), with a hypothesized diversification in the Pleistocene, Zoological Journal of the Linnean Society 175 (1), pp. 20-58 : 29-39

Ixchela azteca SP. NOV.

Type data: MEXICO: Estado de México: 1 ♂ holotype ( CNAN T0763 ) [26 August 2011; A. Valdez, J. Mendoza, D. Barrales, R. Monjaraz, E. Miranda] from Km 46 highway Toluca-Valle de Bravo (lat. 19.2560°, long. −100.0669°; 2315 m). Paratypes : 1 ♀ ( CNAN T0764 ) ; 1 ♀, 3 juv. ( CNAN T0765 ), same data as holotype .

Material examined: MEXICO: Estado de México: 3 ♀♀ (1 with egg sac) ( CNAN) [28 April 2011; A. Valdez, O. Francke, J. Cruz, R. Monjaraz, E. Miranda] from Km 34 highway Toluca-Zitácuaro (lat. 19.3687°, long. −100.0241°; 2730 m). 1 ♂, 1 juv. ( CNAN) [27 August 2011; A. Valdez, J. Mendoza, D. Barrales, R. Monjaraz, E. Miranda] from Cueva del Diablo, La Peña (next to the Microwave Station) (lat. 19.2006°, long. −100.1414°; 1885 m), Valle de Bravo, Municipio Valle de Bravo. 1 ♀ (with egg sac) ( CNAN) [26 August 2011; A. Valdez, J. Mendoza, D. Barrales, R. Monjaraz, E. Miranda] from km 46 highway Villa Victoria-Valle de Bravo (lat. 19.2560°, long. −100.0669°; 2315 m). 4 juv. ( CNAN) [26 August 2011; A. Valdez, J. Mendoza, D. Barrales, R. Monjaraz, E. Miranda] from Reserva Estatal Monte Alto (lat. 19.1930°, long. −100.1122 °; 2152 m), Municipio Valle de Bravo. 2 ♂♂, 1 juv. ( CNAN) [27 August 2011; A. Valdez, J. Mendoza, D. Barrales, R. Monjaraz, E. Miranda] from Cueva de Peña Blanca inside of Rancho La Mecedora (near to Casas Viejas) (lat. 19.1325°, long. −100.1051°; 2149 m), Municipio Valle de Bravo. Distrito Federal: 1 ♂, 3 ♀♀ ( AMNH) [28 February 1973; J. Reddell, D. McKenzie, M. McKenzie, M. Butterwick] from Cueva de Cerro de la Estrella, 2 km S of Iztapalapa (∼lat 19.3267°, long. −99.0918°; 2273 m), Delegación Iztapalapa. 1 ♂ ( CNAN) [13 July 1986; L. M. Ruíz] from Kinchil Mza. 168, Lt. 5, Colonia Heroes de Padierna (∼lat 19.2831°, long. −99.2216°; 2532 m), C. P. 14200, Delegación Tlalpan. 1 ♂ (male grown in the laboratory until the 6th. moult), 3 ♀♀ ( CNAN) [25 June 2009; A. Valdez, H. Montaño, R. Paredes, T. Garrido] from road to Cueva del Fraile (lat. 19.5876°, long. −99.1309°; 2614 m), Delegación Gustavo A. Madero. 1 ♂, 1 juv. ( CNAN) [25 June 2009; A. Valdez, H. Montaño, R. Paredes] from Cueva del Fraile (lat. 19.5938°, long. −99.1283°; 2810 m), Delegación Gustavo A. Madero. 1 ♂ ( CNAN) [25 January 2013; V. Reyes] from Instituto de Biología, UNAM, Cd. Universitaria (lat. 19.3205°, long. −99.1945°; 2327 m), Delegación Coyoacán. Guerrero: 3 ♀♀, 3 juv. ( CNAN) [4 June 2010; A. Valdez. O. Francke, J. Cruz, D. Barrales] from 5 km W of Casahuates (lat. 18.5874°, long. −99.6268°; 2275 m), Municipio Taxco de Alarcón. Michoacán: 2 ♀♀ ( CNAN) [28 April 2011; A. Valdez, O. Francke, J. Cruz, R. Monjaraz, E. Miranda] from El Naranjo (lat. 19.4017°, long. −100.3551°; 2113 m), Municipio Zitácuaro. 2 ♀♀ ( CNAN) [26 November 2012; D. Ortiz, E. Hijmensen, E. Goyer] from 7 km SE of Ciudad Hidalgo (lat. 19.6347°, long. −100.4828°; 1750 m), Municipio Ciudad Hidalgo. 1 ♂, 5 ♀♀, 7 juv. ( CNAN) [29 April 2011; A. Valdez, O. Francke, J. Cruz, R. Monjaraz, E. Miranda] from Gruta de Tziranda (lat. 19.6400°, long. −100.5021°; 1855 m), Municipio Ciudad Hidalgo. Morelos: 1 ♀ ( AMNH) [14 April 1940; C. Bolivar, D. Pelaez] from Parque Nacional de Zempoala. 1 ♀ ( CNAN) [21 May 1978; C. Valdez] from Cueva del Diablo or Ostoyehualco (lat. 18.9952°, long. −99.0601°; 1947 m), Municipio Tepoztlán. 1 ♀ ( CNAN) [21 May 1978; M. M. Oran?], same locality. 5 ♀♀, 2 juv. ( CNAN) [4 December 1977; I. Vázquez], same locality. 2 juv. ( CNAN) [2 July 1978; M. Ortiz], same locality. 2 ♂♂ ( CNAN) [20 December 1977; M. Morales], same locality. 1 ♂ ( CNAN) [4 December 1977; M. Morales], same locality. 1 ♀ ( CNAN) [23 May 1978; M. S. Trejo], same locality. 1 juv. ( CNAN) [21 May 1978; G. Borja], same locality. 2 ♂♂, 5 ♀♀, 33 juv. ( CNAN) [29 July 2009; A. Valdez, O. Francke, C. Santibáñez, T. Palafox, C. Trujano], same locality. 1 ♀ ( CNAN) [25 January 1978; J. Gutierrez] from Tepozteco, Municipio Tepoztlán. 1 juv. ( CNAN) [5 June 1981; V. A. Guillermina] from km 8 road Amatlán Santo Domingo, Municipio Tepoztlán.

Etymology: The specific name is a noun in apposition and is dedicated to the Aztecs, a Mesoamerican culture from central Mexico (dominant from approx. 1428 to 1521 AD), where most of the localities reported for this species are located.

Diagnosis: Resembles I. abernathyi and I. simoni , distinguished from I. abernathyi by the FAC wider and longer ( Figs 37, 40 ); palp femur wider and curved ventrally ( Figs 38, 39 ); epigynum longer, curved, and conical ( Figs 41, 44 ); MSE complete, posteriorly touching the PP ( Fig. 43 ); by the carapace with longer brown markings on each side ( Fig. 35 ); the fovea with straight and wider brown mark around it ( Fig. 35 ); and legs without numerous colour rings; from I. simoni by the FAC conical ( Fig. 40 ); the SAC developed ( Fig. 37 ); the shorter PAB ( Figs 38, 39 ); the palp femur more curved ventrally ( Figs 38, 39 ); the epigynum longer and curved ( Fig. 41 ); the PP wider than long ( Fig. 43 ); and by the oval concavities between MSE and PP more visible ( Fig. 43 ).

Description: Male (Holotype). Prosoma: Carapace beige, with one pale brown mark on each side ( Fig. 35 ). Fovea with irregular, wide and pale brown mark around it, which is joined with the ocular region ( Fig. 35 ). Ocular region dark brown, with a wide line from anterior median eyes to posterior part of the ocular region, one thin brown line from each posterior median eye to posterior part of the ocular region ( Fig. 35 ). Clypeus brown, darker distally ( Fig. 36 ). Chelicerae brown, paler in prolateral proximal part and around the sclerotized apophysis of chelicerae ( Fig. 37 ). Sternum pale orange. Labium and endites brown, white apically. Legs: Coxae pale yellow, grey distally in prolateral and retrolateral parts. Trochanters brown. Femora brown, with a marked wide ring sub-distally; femur IV paler than the others. Patellae dark grey. Tibiae, metatarsi and tarsi pale brown. Tibiae with a dark ring basally and other one distally. Opisthosoma: Conical, pale blue, longer than high ( Figs 34, 35 ). Gonopore plate olive, oval. Palp: Femur orange, conical, paler ventrally, with wide VAF ( Figs 38, 39 ). Patellae and tibia orange. Procursus brown, conical, paler basally, with curved and thin spine distally ( Fig. 38 ). VPP rounded, with numerous long setae ( Fig. 38 ). Embolus conical, with curved dorsal–distal spine, ventrally with sclerotized, long and curved projection ( Figs 38, 39 ). Measurements: Total length (prosoma + opisthosoma) 8.25. Carapace 3.10 long, 2.85 wide. Clypeus 1.20 long. Diameter AME 0.14, ALE 0.24, PME 0.18, PLE 0.23. Distance ALE–PME 0.18, PME– PME 0.34. Leg I: 49.42 (femur 13.62 + patella 1.30 + tibia 13.00 + metatarsi 16.00 + tarsi 5.50), tibia II: 9.37, tibia III: 7.70, tibia IV: 9.50; tibia I (length/diameter) (l/d) 26.00.

Female (Paratype). ( CNAN T 0764). Similar to the male, except by: Prosoma: Carapace with brown markings on each side, which are darker than in male. Fovea with brown mark around it, darker. Ocular region with inconspicuous lines. Clypeus darker brown. Chelicerae darker brown. Sternum, labium and endites darker brown. Legs: Femora darker brown than the male. Epigynum: Wider than long ( Fig. 42 ). PP wide, with MSE strongly sclerotized ( Fig. 43 ). Oval concavities between MSE and PP sac-shaped ( Fig. 43 ). Measurements: Total length 8.00. Carapace 3.10 long, 3.00 wide. Clypeus 1.15 long. Diameter AME 0.13, ALE 0.25, PME 0.20, PLE 0.24. Distance ALE–PME 0.16. PME–PME 0.30. Leg I: 44.19 (11.56 + 1.23 + 12.00 + 14.50 + 4.90), tibia II: missing, tibia III: 6.70, tibia IV: 8.60; tibia I l/d 25.40.

Variation: Male specimens from Cueva del Diablo or Ostoyehualco and from Gruta de Tziranda were notably smaller than specimens from the type locality and the other localities. Female specimens from Grutas de Tziranda and Road to Cueva del Fraile were notably smaller than specimens from the other localities. Specimens from Cueva del Diablo have paler coloration on carapace and legs than the other specimens. There was variation in the opisthosomal coloration: grey, pale grey, blue or pale blue. Males: Cueva del Diablo or Ostoyehualco (N = 4), tibia I: 10.87–12.50 (x = 11.74). Cueva del Diablo, La Peña (N = 1): tibia I: 18.12. Cueva de Peña Blanca (N = 2), tibia I: 13.75, 14.00. Gruta de Tziranda (N = 1): tibia I: 11.00. Road to Cueva del Fraile and Cueva del Fraile, respectively (N = 2): tibia I: 9.50, 12.25. Females: Cueva del Diablo or Ostoyehualco (N = 7): tibia I: 7.50–16.00 (x = 12.77). Km 34 highway Toluca-Zitácuaro (N = 3): tibia I: 6.60–12.5 (x = 9.50). 5 km W of Casahuates (N = 3): tibia I: 9.37–15.25

PHYLOGENY OF IXCHELA 39

(x = 11.95). El Naranjo (N = 2): tibia I: 9.50, 11.75. 7 km SE of Ciudad Hidalgo (N = 2): tibia I: 9.7, 11.37. Gruta de Tziranda (N = 4): tibia I: 7.10–10.2 (x = 8.70). Road to Cueva del Fraile (N = 2): tibia I: 10.12, 11.87.

Natural history: Specimens from Estado de México and Guerrero were collected on their sheet webs in oak– pine and pine forests, inside cavities on walls along road-cuts in wet and shaded areas covered with roots. The male collected in the Instituto de Biología, UNAM, was walking on a wall. The specimens collected from Cueva del Fraile, Distrito Federal and Gruta de Tziranda, Michoacán, were on their sheet webs inside the caves, close to the walls. Specimens collected outside the Cueva del Fraile were among boulders in shady moist areas, whereas specimens from Cueva del Diablo or Ostoyehualco were collected in the cave entrance and inside the cave, where humidity was c. 70% and it was cold. Those specimens were collected on their sheet webs, and it was very common to find prey remains in their webs, mainly large leafcutter ants of the genus Atta (subfamily Myrmicinae ), because there was a nest inside the cave. The ants are a readily avail- able food source for the spiders, which could also explain the high density of the spiders inside the cave.

Distribution: MEXICO: Estado de México, Distrito Federal, Guerrero, Michoacán, Morelos ( Fig. 90 ).

Figures

Figure 90. Known records of Ixchela azteca sp. nov., Ixchela jalisco sp. nov., Ixchela mendozai sp. nov., Ixchela purepecha sp. nov. and Ixchela tlayuda sp. nov.

Figures 34–44. Ixchela azteca sp. nov. Male: 34, 35, Habitus, lateral and dorsal views, respectively. 36, Carapace and chelicerae, frontal view. 37, Chelicerae, frontal view. 38, 39, Left palp, retrolateral and prolateral views, respectively. 40, Chelicera, lateral view. Female: 41, Epigynum, left lateral view. 42, Epigynum, ventral view. 43, Epigynum, dorsal view. 44, Epigynum, frontal view. Scale bars: 0.5 mm (Figs 42, 43), 1 mm (Figs 34–41, 44).