A new species of Loxosceles Heineken & Lowe (Araneae, Sicariidae), with updated distribution records and biogeographical comments for the species from Mexico, including a new record of Loxoscelesrufescens (Dufour) Author Valdez-Mondragon, Alejandro Author Cortez-Roldan, Mayra R. Author Juarez-Sanchez, Alma R. Author Solis-Catalan, Karen P. text ZooKeys 2018 802 39 66 http://dx.doi.org/10.3897/zookeys.802.28445 journal article http://dx.doi.org/10.3897/zookeys.802.28445 1313-2970-802-39 2F0B0C9483D847DFAF571854420D8B70 Loxosceles rufescens (Dufour, 1820) Figs 68-72 Scytodes rufescens Dufour 1820c: 203, pl. 76, fig. 5 (male). Loxosceles citigrada Heineken and Lowe in Lowe (transferred) 1832: 322, pl. 48, figs 1-14 (male, female). See World Spider Catalog (2018) for complete records. Material examined. MEXICO: Chihuahua: 1 male, 1 female (LATLAX-Ara0183) from Instituto de Biomedicas de la Universidad Autonoma de Ciudad Juarez (31. 74645, −106.4444; 1130 m), Municipality Ciudad Juarez , no date, P. Flores col. Diagnosis. L. rufescens resembles Loxosceles foutadjalloni Millot, 1941; in having male palpal tibia wide and a long embolus ( Lotz 2012 : fig. 9C), however in L. rufescens the male palp tibia is wider and the embolus is sigmoid-shaped (Figs 68-69), whereas in L. foutadjalloni the embolus is long and curved ( Lotz 2012 : fig. 9C). Females resemble L. foutadjalloni by the shape of the seminal receptacles ( Lotz 2012 : fig. 10B), however in L. rufescens they are short and round distally (Fig. 70), whereas in L. foutadjalloni the seminal receptacles are longer and distally bifurcated and rounded ( Lotz 2012 : fig. 10B). Description. See Chomphuphuang et al. (2016). Distribution. Loxosceles rufescens (Figs 68-72) has a natural distribution in the Mediterranean Basin and the Middle East ( Nentwig et al. 2017 ; Tahami et al. 2017 ), but also is considered a cosmopolitan species ( Nentwig et al. 2017 ; World Spider Catalog 2018 ). Remarks. In Mexico, L. rufescens is only known from two records, from the states of Tamaulipas and Chihuahua (Fig. 73). Chickering (1937) reported L. rufescens from San Carlos Mountains, Tamaulipas; however, he never described or illustrated any specimen, which makes his record questionable (Fig. 74). Updated distribution records for the 39 species of Loxosceles from Mexico. A total of 461 records of the 39 species of Loxosceles distributed in Mexico were reviewed. Twenty records were discarded for not having complete localities or having doubtful georeferences. Thus, a total of 441 records were used to make the distribution maps (Figs 73-76). The states with the most records are Guerrero with 55, Mo relos with 35, and Baja California Sur with 30 (Fig. 75). The state of Tabasco only has a single record (Appendix 1, Fig. 75). The most diverse states are Baja California Sur, Baja California, Sonora (with five species each), Guerrero, Tamaulipas (with four species each), and Oaxaca, Puebla, Hidalgo, Coahuila, San Luis Potosi , Nuevo Leon (with three species each) (Figs 73, 74). The least diverse states are Durango, Zacatecas, Michoacan , Queretaro , Chihuahua and Sinaloa (with two species each); Jalisco, Guanajuato, Quintana Roo, Colima, Chiapas, Yucatan, Campeche, Tabasco, Veracruz, Mexico City, Nayarit, Aguascalientes, Tlaxcala and state of Mexico (with a single species each) (Figs 73-76). Regarding the number of total records per species of Loxosceles , the species with the most records are L. boneti with 59 and L. colima with 57 (Fig. 75). The species with the least number of records are L. barbara , L. carmena , L. francisca , L. insula , L. luteola and L. rufescens with a single record each (Fig. 74). A new record of L. misteca was found for Tlaxcala (Figs 75). A third record of L. reclusa was found for Tamaulipas (Fig. 74). The record of L. rufescens from Ciudad Juarez , Chihuahua represents the second record for the country of this introduced species and the first well-documented and illustrated record from Mexico (Figs 68-72, 73, Appendix 1). Figures 68-72. Loxosceles rufescens Dufour, 1820, from Ciudad Juarez , Chihuahua, Mexico68, 69 Male, left palp, prolateral and retrolateral views respectively 70 Female, seminal receptacles, dorsal view 71, 72 Caparace dorsal view, male and female views respectively. Scale bars: 0.5 mm (68, 69), 0.2 mm (70), 1 mm (71, 72). Figures 73-74. Updated records of the species of Loxosceles for the states of north of Mexico. Asterisk in L. rufescens represents a new record for Mexico. Abbreviations for the Mexican states: BC, Baja California; BCS, Baja California Sur; CHIH, Chihuahua; COAH, Coahuila; DGO, Durango; NL, Nuevo Leon ; SIN, Sinaloa; SLP, San Luis Potosi ; SON, Sonora; TAMS, Tamaulipas; ZAC, Zacatecas. Figures 75-76. Updated records of the species of Loxosceles for the states of central region and south of Mexico. Abbreviations for the Mexican states: AGS, Aguascalientes; CAM, Campeche; CDMX, Mexico City; CHIS, Chiapas; COL, Colima; MEX, Estado de Mexico ; GTO, Guanajuato; GRO, Guerrero; HGO, Hidalgo; JAL, Jalisco; MICH, Michoacan ; MOR, Morelos; NAY, Nayarit; OAX, Oaxaca; PUE, Puebla; QR, Quintana Roo; QRO, Queretaro ; TAB; Tabasco; TLAX, Tlaxcala; VER, Veracruz; YUC, Yucatan . Figures 77-78. 77 Biogeographical provinces of Mexico showing the distribution records of the genus Loxosceles 78 Known records of Loxosceles malintzi sp. n. from the Depression of the Balsas province (green area), including the type locality.