Ixchela tlayuda, 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 : 42-44

Ixchela tlayuda SP. NOV.

Type data: MEXICO: Oaxaca: 1 ♂ holotype ( CNAN T0787 ) [4 November 2012; C. Santibáñez] from San Pablo Etla, forest La Nevería (lat. 17.1668°, long. −96.6851°; 2981 m), Distrito Etla, Municipio San Pablo Etla. Paratypes : 1 ♀ ( CNAN T0788 ) , 2 ♀♀ ( CNAN T0789 ), same data as holotype .

Material examined: MEXICO: Oaxaca: 2 ♀♀, 5 juv. ( CNAN) [19 September 2009; A. Valdez, C. Santibáñez, R. Paredes, J. Cruz] from San Felipe del Agua (lat. 17.1162°, long. −96.7095°; 2001 m), Municipio San Felipe del Agua . 1 ♂ ( CNAN) [19 February 2005; G. Gutierrez], same locality . 1 ♀ ( CNAN) [12 November 2005; O. Francke, G. Montiel, C. Santibáñez], same locality . 1 ♀ ( CNAN) [18 June 2007; A. Valdez, C. Santibáñez] from Campamento del Monte, El Punto (lat. 17.2011°, long. −96.5879°; 2500 m), Municipio Sta. Catarina Ixtepeji , Distrito Ixtlán . 1 ♂, 2 ♀♀ ( CNAN) [27 November 2010; G. Montiel, M. Hernández, R. Paredes] from Parador Ecoturistico del Monte, 3 km S of El Punto (lat. 17.2017°, long. −96.5911°; 2537 m), Municipio Sta. Catarina Ixtepeji . 2 ♂♂, 2 ♀♀ (with egg sac) ( CNAN) [26 March 2010; A. Valdez, O. Francke, C. Santibáñez, J. Cruz] from 9 km N of San Miguel Etla, road to Las Guacamayas (lat. 17.2247°, long. −96.7385°; 2197 m), Municipio San Miguel Etla, Distrito San Miguel Etla . 3 ♀♀ (2 with egg sac), 2 juv. ( CNAN) [23 April 2010; A. Valdez, C. Santibáñez, J. Cruz, D. Barrales] from Km 189 road Tuxtepec-Oaxaca (lat. 17.1934°, long. −96.6001°; 2561 m) . 3 ♂♂, 4 ♀♀ (one with egg sac), 1 juv. CNAN) [22 April 2010; A. Valdez, C. Santibáñez, J. Cruz, D. Barrales] from Campamento Las Flores (lat. 17.3509°, long. −96.5312°; 2320 m), Municipio Santa María Jaltianguis, Distrito Ixtlán . 1 ♂, 1 ♀, 2 juv. ( CNAN) [18 September 2009; A. Valdez, C. Santibáñez, R. Paredes] from Centro Recreativo Calpulalpan de Méndez (lat. 17.3228°, long. −96.4452°; 2000 m), Distrito Ixtlán . 2 ♀♀ ( CNAN) [22 April 2010; A. Valdez, C. Santibáñez, J. Cruz, D. Barrales], same locality . 1 ♂, 3 ♀♀, 2 juv. ( CNAN) [18 September 2009; A. Valdez, C. Santibáñez, R. Paredes] from La Trinidad (lat. 17.2865°, long. −96.4379°; 2268 m), Distrito Ixtlán de Juárez . 1 ♂ ( CNAN) [3 April 2005; Col.?] from Tierra Colorada, Distrito Ixtlán de Juárez . 1 ♀ ( CNAN) [22 July 2007; A. Valdez, O. Francke, H. Montaño, C. Santibáñez, A. Ballesteros] from Campamento Tatachinto (lat. 17.2876°, long. −96.4176°; 2326 m), Municipio Santiago Xiacuí, Distito Ixtlán de Juárez . 1 ♀ ( CNAN) [3 November 2005; A. Valdez, O. Francke, H. Montaño] from road to Magdalena Mixtepec (lat. 16.9301°, long. −96.8742°; 2676 m) . 1 ♂ ( CNAN) [16 March 2008; A. Valdez, C. Satibáñez, H. Montaño] from La Trinidad, Santiago Xiacuí (lat. 17.2865°, long. −96.4377°; 2258 m) . 5 ♀♀, 1 juv. ( CNAN) [11 September 2010; A. Valdez, O. Francke, J. Cruz, D. Barrales] from 1 km W of Puerto de la Soledad (lat. 18.1754°, long. −97.0050°; 2245 m), Municipio Huautla de Jiménez . 1 ♀, 2 juv. ( CNAN) [15 March 2008; A. Valdez, H. Montaño, C. Santibáñez] from Tlahuitoltepec (lat. 17.0927°, long. −96.0547°; 2040 m), Municipio Santa María Tlahuitoltepec, Distrito Mixes . 1 ♂ ( CNAN) [14 September 2009; A. Valdez, C. Santibáñez, R. Paredes ], same locality . 1 ♀ ( CNAN) [14 September 2009; A. Valdez, C. Santibáñez, R. Paredes] from Puente Azul (lat. 17.0026°, long. −96.1193°; 1862 m), Municipio Ayutla .

Etymology: The specific name is a noun in apposition and refers to ‘Las Tlayudas’, a popular dish in central Oaxaca, where the type locality is located.

Diagnosis: Resembles I. abernathyi and I. mendozai , but distinguished from I. abernathyi by FAC wider and longer, ending in a small tip ( Fig. 85 ); the pattern around the fovea wider ( Fig. 80 ); the VAF longer ( Fig. 83 ); the central apex of the epigynum longer and curved ( Fig. 86 ); the lateral apex of the epigynum more rounded and larger ( Figs 87, 89 ); and the opisthosoma more conical ( Fig. 79 ); from I. mendozai by the FAC ending in a small tip ( Figs 82, 85 ), whereas on I. mendozai the FAC are wider and rounded distally ( Fig. 62 ); the median distal protuberance of the epigynum shorter ( Figs 86, 89 ), which is not as wide and curved as on I. mendozai ( Figs 66, 67 ); and the MSE which does not touch the PP ( Fig. 88 ), whereas in I. mendozai the MSE touches the PP ( Fig. 65 ).

Description: Male (Holotype). Prosoma: Beige, with three small, brown markings on each side ( Fig. 80 ). Ocular region brown, with a grey longitudinal line project- ing from AME ( Fig. 80 ). Fovea surrounded with wide, grey, irregular region, extending backward ( Fig. 80 ). Clypeus beige, with a distal, dark grey region ( Fig. 81 ). Chelicerae brown, pale on basal part and around the SAC ( Fig. 82 ). Sternum pale yellow. Labium and endites dark grey; endites with a weak retrolateral apophysis, with a small, subdistal protuberance. Legs: Coxae pale yellow, distally with greey region on prolateral and retrolateral parts. Trochanters pale brown. Femora pale orange; femora I–III brown basally, with several pale grey rings throughout their length; one dark grey subdistal ring, wide, very marked. Patellae grey. Tibiae pale orange, with several grey rings throughout their length, less visible than on femora. Metatarsi and tarsi orange, without colour rings. Legs with numerous oblique, long setae; with few short, erect setae. Opisthosoma: Conical, longer than high, pale grey ( Figs 79, 80 ). Gonopore plate oval, pale olive. Palp: Femur pale yellow, basally grey on dorsal part, with several long setae ventrally, with VAF conical ( Fig. 83 ). Patellae and tibia pale orange, basally grey on dorsal part. Procursus brown, basally pale orange on dorsal part, with distal, curved spine ( Fig. 83 ). VPP with 3–5 long setae ( Fig. 83 ). Embolus conical, dorsally with small curved spine ( Figs 83, 84 ), ventrally with long curved sigmoid projection ( Figs 83, 84 ). PAB wide ( Fig. 84 ). Measurements: Total length 6.90. Carapace 2.70 long, 2.40 wide. Clypeus 1.15 long. Diameter AME 0.16, ALE 0.25, PME 0.18, PLE 0.20. Distance ALE–PME 0.16, PME–PME 0.28. Leg I: 45.55 (12.12 + 1.06 + 12.00 + 15.75 + 4.62), tibia II: 8.80, tibia III: 6.90, tibia IV: missing. Tibia I l/d: 28.00.

Female (Paratype). ( CNAN T 0788). Similar to the male, but with the following differences: Prosoma: Carapace with the three markings darker and larger than on male. Fovea surrounded by irregular brown area. Clypeus with brown region U-shaped. Chelicerae darker brown than on the male. Sternum yellow, with lateral dark grey markings. Labium and endites brown. Legs: Femora, patellae, tibiae, metatarsi, and tarsi darker than on the male. Legs with rings throughout their length, more noticeable than on the male. Opisthosoma: Pale blue. Epigynum: Wider than long, with three rounded projections distally ( Figs 86, 87, 89 ); small rounded pit on central projection ( Fig. 87 ). PP wide; with small oval, sac-shaped concavities between MSE and PP ( Fig. 88 ). The MSE does not touch the PP ( Fig. 88 ). Measurements: Total length 9.40. Carapace 3.40 long, 2.90 wide. Clypeus 1.30 long. Diameter AME 0.12, ALE 0.28, PME 0.20, PLE 0.20. Distance ALE–PME 0.18. PME–PME 0.28. Leg I: 46.85 (12.00 + 1.30 + 12.81 + 15.37 + 5.37), tibia II: 9.10, tibia III: 7.10, tibia IV: 9.20; tibia I l/d 29.28.

Variation: The carapace pattern is brown, dark brown, grey or dark grey, and in some specimens this pattern is more marked than others. The legs are brown, pale yellow, dark orange or dark brown; some specimens have colour rings on femur and tibiae more marked than others. Some specimens have opisthosoma pale blue, grey or pale yellow. Males: Parador Ecoturístico del Monte, 3 km S of El Punto (N = 1): tibia I: 11.37. Centro Recreativo Calpulalpan de Méndez (N = 1): tibia I: 13.75. Campamento las Flores (N = 3): tibia I: 10.50– 11.87 (x = 10.99). La Trinidad (N = 1): tibia I: 13.25. San Felipe del Agua (N = 1): tibia I: 14.56. Females: Parador Ecoturístico del Monte, 3 km S of El Punto (N = 2): tibia I: 11.35, 11.37. La Trinidad (N = 2): tibia I: 10.10, 11.12. 1 km W of Puerto de la Soledad (N = 5): tibia I: 9.18–10.75 (x = 10.39). Campamento las Flores (N = 4): tibia I: 8.37–11.12 (x = 9.34). San Felipe del Agua (N = 2): tibia I: 12.37, 13.43.

Natural history: The specimens from different localities were collected on their sheet webs in oak, pine or mixed oak–pine forests. The specimens from San Felipe del Agua were collected along road-cuts in wet and shaded areas near a river. The specimens from Campamento del Monte, El Punto and from 9 km north of San Miguel Etla, road to Las Guacamayas, were collected under large fallen logs and boulders on the ground. Some specimens from Campamento Las Flores were collected under and among fallen logs; others were collected inside hollows at the bases of pine trees. Some specimens from Centro Recreativo Calpulalpan de Méndez were collected in holes on a large karstic wall next to a river, others among fallen logs and boulders on the ground near the river, a location with a high humidity (c. 80%). The specimens from La Trinidad were collected among numerous boulders on the ground. The specimens from Tlahuitoltepec were collected under fallen logs in a disturbed pine forest; note that those specimens were collected outside the Cueva de Tlahuitoltepec, which is the type locality of Ixchela mixe Valdez-Mondragón, 2013 , so they could be sympatric species.

Distribution: MEXICO: Oaxaca ( 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 79–89. Ixchela tlayuda sp. nov. Male: 79, 80, Habitus, lateral and dorsal views, respectively. 81, Carapace and chelicerae, frontal view. 82, Chelicerae, frontal view. 83–84, Left palp, retrolateral and prolateral views, respectively. 85, Chelicera, lateral view. Female: 86, Epigynum, left lateral view. 87, Epigynum, ventral view. 88, Epigynum, dorsal view. 89, Epigynum, frontal view. Scale bars: 0.5 mm (Figs 82, 85, 88), 1 mm (Figs 79–81, 83, 84, 86, 87, 89).

Figures 56–67. Ixchela mendozai sp. nov. Male: 56, 57, Habitus, lateral and dorsal views, respectively. 58, Carapace and chelicerae, frontal view. 59, Chelicerae, frontal view. 60, 61, Left palp, retrolateral and prolateral views, respectively. 62, Chelicera, lateral view. 63, Bulb and embolus, prolatero-dorsal view (arrow indicates the curved and sharp subdistally sclerotized spine). Female: 64, Epigynum, ventral view. 65, Epigynum, dorsal view. 66, Epigynum, left lateral view. 67, Epigynum, frontal view. Scale bars: 0.5 mm (Figs 58, 59, 62–67), 1 mm (Figs 56, 57, 60, 61).