Oecobius yoreme, Alcántar-Valenzuela & Chamé-Vázquez & Jiménez, 2025

Alcántar-Valenzuela, Joel Jair, Chamé-Vázquez, David & Jiménez, María-Luisa, 2025, Four new species of the spider genus Oecobius Lucas, 1846 (Araneae: Oecobiidae) from northwestern Mexico, Zootaxa 5679 (4), pp. 501-520 : 510-512

Oecobius yoreme spec. nov.

Figs 31–40 , 67–69

Type material. Holotype: 1♂ (CARCIB-Ar-034): MEXICO: Sinaloa, El Fuerte, Cerro “La Máscara” (26.4369°N, 108.6242°W, 106 m), tropical deciduous forest, manual collection, J. Alcántar leg., 07/II/2022.

Paratypes: Same data as for holotype, 1♀ (CARCIB-Ar-035); Ahome, Bolsa de Tozalibampo Dos (26.1015°N, 109.1896°W, 11 m), manual collection, J. Alcántar leg., 15/I/2022, 2♂ 3 juvs (CARCIB-Ar-0223); Choix, La Estancia Baymena (26.5741°N, 108.2664°W, 427 m), exterior of a house in the wall, manual collection, J. Alcántar leg., 11/VI/2021, 1♂ 4 juvs (CARCIB-Ar-0226); same data as for preceding, except 25/VII/2022, 3♂ 6♀ 1 juv. (CARCIB-Ar-354); El Fuerte, El Fuerte in Cerro of “La Máscara” (26.4369°N, 108.6242°W, 106 m), tropical deciduous forest, manual collection, J. Alcántar leg., 07/II/2022, 2♂ 2♀ 5 juvs (CARCIB-Ar-0227); Sinaloa de Leyva, Maripa, (25.8609°N, 108.1586°W, 75 m), under of a stone in exterior of a house, manual collection, J. Alcántar leg., 17/I/2022, 1♂ 1♀ (CARCIB-Ar-0222); Baburía, Baburía cemetery (25.8500°N, 108.1904°W, 67 m), manual collection, J. Alcántar leg., 02/XI/2022, 1♀ (CARCIB-Ar-0220); same data as for preceding, except 02/ XI/2021, 2♀ 5 juvs (CARCIB-Ar-0224); 1.45 km of Matapán del Llano , (25.9096°N, 108.1142°W, 91 m), tropical deciduous forest, manual collection, J. Alcántar leg., 18/I/2022, 4♂ 14 juvs (CARCIB-Ar-0225) .

Etymology. The specific epithet refers to the Yoreme-Mayo, an indigenous ethnic group that lives in northern Sinaloa and southern Sonora.

Diagnosis. Male palp of O. yoreme spec. nov. resembles those of O. yaqui spec. nov. by having the radical apophysis of about the same length as terminal apophysis; however, O. yoreme spec. nov. possesses the base of terminal apophysis striated (arrow in Figs 35, 36 ; vs. not striated in O. yaqui spec. nov., Figs 25, 26 ) and apically hook-shaped, as seen in prolateral and retrolateral views ( Figs 35, 37 ; vs. apically straight in O. yaqui spec. nov., Figs 25, 27 ). Females of O. yoreme spec. nov. resemble those of Oecobius yaqui spec. nov. by having the scape longer than wide; however, O. yoreme spec. nov. has a subrectangular-shaped scape ( Fig. 38 ; vs. oval in Oecobius yaqui spec. nov., Fig. 28 ) and a notched apex of the scape ( Fig. 38 ; vs. not notched in Oecobius yaqui spec. nov., Fig. 28 ).

Description. Male. Coloration: Carapace brown with three dark and three white submarginal spots, and one small spot in the clypeal area. The eye area bordered with black. Legs pale whitish, with black rings on segments (usually broken) as follows: Fe with two, Pa with one, Ti with two, Mt with two, Ta with one, very diffused distally. Sternum, labium and endites pale brown. Opisthosoma dorsum with white and dark spots, brown cardiac mark; sides suffused with dark spots. Opisthosoma venter dark brown anteriorly and posteriorly, median area whitish, with few white spots. Spinnerets and anal tubercle light brown.

Carapace, eyes, mouthparts, and opisthosoma as in Oecobius culichi spec. nov. Measurements: total length 1.89. Carapace 0.83 long, 0.89 wide. Opisthosoma 1.07 long, 0.80 wide. Ti I 0.54, II 0.63, III 0.60, IV 0.63.

Palp. In prolateral view, radical apophysis subrectangular, apically blunt and broad; radical protrusion short, subtriangular, and pointed; terminal apophysis with broad base, ventrally striated, apically curved (hook-shaped), tip somewhat flattened and concave, same apophysis with a lamelliform process below embolus ( Figs 35–37 ). Conductor with two spiniform processes directed retroventrally, the subapical one hyaline, medial one slightly sclerotized; embolus filiform, directed retrolaterally ( Figs 68–69 ).

Female. Coloration: Similar to male, but carapace spots diffused. Opisthosoma dorsum brownish with white and black spots; opisthosoma a wide venter median area light brown, without few white spots. Measurements: total length 2.72. Carapace 0.73 long, 0.75 wide. Opisthosoma 1.99 long, 1.40 wide. Ti I 0.57, II 0.60, III 0.58, IV 0.64.

Epigyne. Scape longer than wide, subrectangular, apically notched; copulatory openings situated in scape notch. Vulva . Copulatory ducts long, directed anteriorly then arched laterally toward receptacles; receptacles hyaline and globose; sclerotized capsules elongated, arched, situated laterally at scape base; blind appendix reniform, restricted to posterior fifth of the epigynal length ( Figs 38–39 ).

Variation. The coloration of males is usually darker than females. The number of white spots on opisthosoma venter varies, but females generally have a reduced number of white spots. Measurements: Females (N=3) Total length 2.38–3.29. Carapace 0.73–1.00 long, 0.75–1.13 wide. Opisthosoma 1.66–2.28 long, 1.36–1.72 wide. Ti I 0.53–0.76, II 0.55–0.78, III 0.51–0.76, IV 0.60–0.79. Males (N=3): Total length 1.89–2.48. Carapace 0.83–0.99 long, 0.89–1.16 wide. Opisthosoma 1.07–1.16 long, 0.80–1.49 wide. Ti I 0.54–0.73, II 0.63–0.76, III 0.60–0.72, IV 0.63–0.73.

Natural history. Specimens of this species were found under rocks, although some were observed inhabiting house walls. In January and February of 2022, 10 round ovisacs were found, with a range of 3 to 9 eggs (N=10).

Distribution. An endemic species known only from northern Sinaloa ( Fig. 76 ).

Figures

FIGURE 76. Distribution of Oecobius species based on records from the current paper, Shear (1970), and Jiménez & Llinas (2005).

FIGURES 31–40. Oecobius yoreme spec. nov. 31. male habitus, dorsal; 32. same, ventral; 33. female habitus, dorsal; 34. same, ventral; 35. male palp, prolateral; 36. same, ventral; 37. same, retrolateral; 38. epigyne, ventral; 39. cleared epigyne, ventral; 40. same, dorsal. White arrows point grooves of the terminal apophysis in Figs. 35, 36. Scale bars 31–34: 1.0 mm; 35–37: 0.30 mm; 38–40: 0.10 mm. Abbreviations: BA—blind appendix; C—conductor; CD—copulatory ducts; CO—copulatory openings; E— embolus; FD—fertilization ducts; K—sclerotized capsule; R—receptacle; RA—radical apophysis; TA—terminal apophysis.

FIGURES 61–69. 61–63. Oecobius culichi spec. nov. 64–66. O. sudcaliforniana spec. nov. 67–69. O. yoreme spec. nov. 61, 64, 67. male palp, prolateral. 62, 65, 68. same, ventral. 63, 66, 69. same, retrolateral. The processes of the conductor are colorcoded as follows: green for the subapical process, red for the median process, and blue for the subbasal process. Scale bars 61–69: 0.10 mm. Abbreviations: C—conductor; E—embolus; RA—radical apophysis; RP—radical protrusion; TA—terminal apophysis.

FIGURES 21–30. Oecobius yaqui spec. nov. 21. male habitus, dorsal; 22. same, ventral; 23. female habitus, dorsal; 24. same, ventral; 25. male palp, prolateral; 26. same, ventral; 27. same, retrolateral; 28. epigyne, ventral; 29. cleared epigyne, ventral; 30. same, dorsal. Scale bars 21–24: 1.0 mm; 25–27: 0.30 mm; 28–30: 0.10 mm. Abbreviations: BA—blind appendix; C— conductor; CD—copulatory ducts; CO—copulatory openings; E—embolus; FD—fertilization ducts; K—sclerotized capsule; R—receptacle; RA—radical apophysis; TA—terminal apophysis.