Pholcidae C. L. Koch, 1850

Valdez-Mondragón, Alejandro, 2020, COI mtDNA barcoding and morphology for species delimitation in the spider genus Ixchela Huber (Araneae: Pholcidae), with the description of two new species from Mexico, Zootaxa 4747 (1), pp. 54-76 : 54-76

Family Pholcidae C. L. Koch, 1850

Genus Ixchela Huber, 2000

Type species. Coryssocnemis furcula F. O. Pickard-Cambridge, 1902 , by original designation of Huber (2000). Type locality: female holotype from Tecpam, Región de los Altos (Cerro Tecpam, Departmento Chimaltenango), Guatemala, around 2300 m, Otto Stoll. Godman & Salvin Coll., in BMNH (F. O. Pickard-Cambridge 1902; Huber 1998).

Diagnosis and Description. For an updated diagnosis and description of the genus see Valdez-Mondragón (2013) and Valdez-Mondragón and Francke (2015).

Composition. 22 species: Ixchela simoni (O. Pickard-Cambridge, 1898) , Ixchela abernathyi (Gertsch, 1971) , Ixchela furcula (F. O. Pickard-Cambridge, 1902) , Ixchela pecki (Gertsch, 1971) , Ixchela placida (Gertsch, 1971) , Ixchela mixe Valdez-Mondragón 2013 , Ixchela huberi Valdez-Mondragón 2013 , Ixchela juarezi Valdez-Mondragón 2013 , Ixchela grix Valdez-Mondragón 2013 , Ixchela taxco Valdez-Mondragón 2013 , Ixchela franckei Valdez-Mondragón 2013 , Ixchela tzotzil Valdez-Mondragón 2013 , Ixchela santibanezi Valdez-Mondragón 2013 , Ixchela huasteca Valdez-Mondragón 2013 , and Ixchela viquezi Valdez-Mondragón 2013 , Ixchela azteca Valdez-Mondragón & Francke 2015 , Ixchela jalisco Valdez-Mondragón & Francke 2015 , Ixchela mendozai Valdez-Mondragón & Francke 2015 , Ixchela purepecha Valdez-Mondragón & Francke 2015 , Ixchela tlayuda Valdez-Mondragón & Francke 2015 , Ixchela panchovillai sp. nov., and Ixchela zapatai sp. nov.

Distribution. Ixchela is a widely distributed genus from North-eastern Mexico to Nicaragua. Although in this work the specimens from Nicaragua were not examined, Huber (2000) examined one male of an undescribed species from such country deposited in Museo Entomológico Nicaraguense (León, Nicaragua).

Natural History. The genus Ixchela has a natural distribution in temperate climate zones, principally in pine, oak, or pine-oak forest, between 1000-2950 m of elevation ( Figs. 29, 30 ; Valdez-Mondragón 2013: figs. 13‒15, 17, 18), however some species like Ixchela santibanezi and I. juarezi were collected in tropical rain forest at 1190 m ( Valdez-Mondragón 2013: fig. 16), or in a thorny scrub forest at 1900-2180 m respectively. Although there has been intensive collecting at low elevations, it seems that the genus Ixchela only occurs above 1000 m of elevation ( Valdez-Mondragón 2013, Valdez-Mondragón & Francke 2015), while below this elevation only other genera such as Physocyclus Simon, 1893 and Psilochorus Simon, 1893 have been collected, principally in deciduous tropical forest.

The spiders sampled during new fieldwork were found among fallen logs, boulders on the ground, under dry leaves of agave plants, and frequently on their irregular sheet webs on embankments along road-cuttings, specifically in shaded, moist areas covered with roots and leaf-litter ( Figs 29, 30 ). In karst zones, the spiders are frequently found in sheet webs-inside caves ( Valdez-Mondragón 2013: fig. 14) on walls, holes in walls, among boulders on the floor, or among karst formations (stalagmites and columns) ( Valdez-Mondragón 2013: figs. 1‒3, 5, 9). Although some species have been collected frequently inside caves, at relatively high densities, all species can be considered troglophiles and not strict troglobites or with conspicuous troglomorphic modifications ( Valdez-Mondragón 2013: figs 1‒12).

Figures

FIGURES 25–30. 25–28, Living specimens (females) of Ixchela zapatai sp. nov. from type locality. 29–30, Temperate pine-oak forest at 2399 m.a.s.l. at the type locality (red arrow indicates the microhabitat where the specimens of I. zapatai sp. nov were collected).