Trachelas crassus, Rivera-Quiroz, F. Andrés & Alvarez-Padilla, Fernando, 2015

Rivera-Quiroz, F. Andrés & Alvarez-Padilla, Fernando, 2015, Three new species of the genus Trachelas (Araneae: Trachelidae) from an oak forest inside the Mesoamerican biodiversity hotspot in Mexico, Zootaxa 3999 (1), pp. 95-110 : 97-100

Trachelas crassus sp. n.

Figures 1–17

Type material. ♂ holotype: MEXICO: Veracruz: Atotonilco de Calcahualco, near the Pico de Orizaba National Park (19°08'17.4"N, 97°12'16.2"W, 2 300 m), collected 4–14 October 2012, M. Hernández-Patricio ( CAFC- UNAM).

♀ allotype from the same locality, collected 15–24 February 2013 by F.A. Rivera-Quiroz (CAFC-UNAM).

Paratypes: MEXICO: Veracruz: Atotonilco de Calcahualco, Plot I, 19°08'30.2"N, 97°12'21.5"W, 2 238 m, 15– 24 February 2013, M. Servín-Pastor, 1♂ ( MCZ). Same locality, Plot II, 19°08'17.4"N, 97°12'16.2"W, 2 300 m, 4– 14 October 2012, F. Alvarez-Padilla, 1♀ ( MCZ), 1♀ ( CAS); Same data as previous but F.A. Rivera-Quiroz, 1♂ ( CAS).

Other material examined. N = 41. MEXICO: Veracruz: Atotonilco de Calcahualco, Plot I, 19°08'30.2"N, 97°12'21.5"W, 2 238 m, 21–30 May 2012, 1♀ (CAFC-UNAM); 4–14 October 2012, 6♀, 5♂ (CAFC-UNAM); 15– 24 February 2013, 1♀, 1♂ (CAFC-UNAM). Same locality, Plot II, 19°08'17.4"N, 97°12'16.2"W, 2 300 m, 21–30 May 2012, 3♀, 2♂ (CAFC-UNAM); 4–14 October 2012, 7♀, 1♂ (CAFC-UNAM); 15–24 February 2013, 10♀ (CAFC-UNAM).

Etymology. The species epithet is an adjective from the Latin crasso (thick) and refers to the basal portion of the fertilization duct that is almost as wide as the S.

Diagnosis. The male of T. crassus sp. n. is similar to T. lanceolatus F.O. P.-Cambridge, 1899 and T. odoreus sp. n. by the palpal tibia at least 0.6 times as long as the cymbium ( Figs 15, 16 ; Platnick & Shadab 1974a: fig. 73), but differs from these two species by the E longer and curved clockwise ( Fig. 17 ; Platnick & Shadab 1974a: fig. 72) and the straight RTA with a blunt tip on ventral view ( Figs 17 , 51 ; Platnick & Shadab 1974a: fig. 72), respectively. Female genitalia of T. crassus sp. n. are similar to those of T. hamatus Platnick & Shadab, 1974 and T. latus Platnick & Shadab, 1974 by having the S and Ss of similar length ( Figs 11 , 14 ; Platnick & Shadab 1974a: figs 83, 87), but differ from these two species by the FD curled distally and the less coiled CD, respectively.

Description. Male: Total length 9.05. Cephalothorax: 4.7 long. Carapace glabrous, without pattern, coloration reddish-brown, darker in ocular area, becoming lighter towards posterior edge, thoracic grooves deep, darker than surrounding cuticle ( Fig. 2 ). Lateral and dorsal surfaces same color, cephalic area higher than thoracic ( Fig. 4 ). Sternum glossy, almost same color as rear portion of carapace, darker at margins ( Fig. 2 ). AME closer together than to ALE. Clypeus about one diameter of AME. All eyes subequal in size ( Fig. 1 ). AER slightly procurved, PER procurved in dorsal view. Endites and labium dark brown, longer than wide, labium length ca. 3/4 of endites, darker in color. Chelicera dark red, greatly sclerotized, with rugose cuticle. Three promarginal and two retromarginal teeth. Abdomen length 4.7. Dorsal surface pale grey, covered by reddish longitudinal scutum, with leaf-like venation pattern under it ( Fig. 2 ). Ventral surface light yellow, with four narrow lines of sclerotized red spots. Book lungs covers reddish, epigastric area slightly sclerotized ( Fig. 6 ). Leg formula I-II-IV-III, first pair darker, second pair light yellow. VCT 43, VCM 38. Pedipalp light yellow, bulb reddish ( Figs. 3, 5 ). Tibia long about 0.6 times length of cymbium, RTA short, about 0.2 times width of tibia.

Female: as in male except as noted ( Fig. 8, 10, 12 ). Total length 10.5. Cephalothorax: 4.7 long. Abdomen length 5.3, without dorsal scutum, with lateral striated pattern composed of lighter lines ( Fig. 10 ). Ventral surface with two longitudinal narrow lines of sclerotized red spots. Book lungs not as sclerotized as in male ( Fig. 12 ). VCT 20, VCM 28. Epigynum red, with semi-transparent cuticle, atrium round, copulatory openings on middle portion, separated ( Fig. 9 ); CD long, narrow, coiling around CO and FD ( Fig. 13 ). FD with proximal part as wide as S, followed by S-shaped turns, with accessory gland openings on distal portion ( Fig. 14 ).

Variation. Males: total length mean 9.05 (range: 8.0 to 9.8), carapace mean 4.7 (range: 4.0 to 5.1). Number of ventral cusps greatly variable, VCT mean 27.6 (range: 17 to 43), VCM mean 33.3 (range: 28 to 38). Females: total length mean 10.1 (range: 8.5 to 11.4), carapace mean 4.7 (range: 4.0 to 5.9). Ventral cusps also variable, VCT mean 25.0 (range: 16 to 34) and VCM mean 31.5 (range: 19 to 38).

Distribution. Known only from the type locality ( Fig. 52 ).

Biology. All specimens were collected in a Quercus forest with secondary plant growth. Adult specimens were found during all three expeditions. Most specimens were caught by beating and direct collecting over vegetation; only one specimen found in cryptic search.

Figures

FIGURE 52. Map of the locality where T. crassus, T. ductonuda and T. odoreus were collected near Pico de Orizaba (Veracruz) marked with an X. Scale bar = 200 km.

FIGURES 1 – 6. Trachelas crassus sp. n., male. 1 Prosoma, anterior view; 2 Habitus, dorsal view; 3 Palp, retrolateral view; 4 Habitus, lateral view; 5 Palp, ventral view; 6 Habitus, ventral view. Scale bars: 1, 2, 4, 6 = 1.0 mm; 3, 5 = 0.5 mm.

FIGURES 7 – 12. Trachelas crassus sp. n., female. 7 Prosoma, anterior view; 8 Habitus, dorsal view; 9 Epigynum, ventral view; 10 Habitus, lateral view; 11 Epigynum, dorsal view; 12 Habitus, ventral view. Scale bars: 7, 9 = 0.5 mm; 8, 10, 12 = 1.0 mm; 11 = 0.2 mm.

FIGURES 13 – 17. Trachelas crassus sp. n., genitalia. 13 Epigynum, cleared ventral view; 14 Same, dorsal view; 15 Palp, prolateral view; 16 Same, retrolateral view; 17 Same, ventral view. Scale bars: 13, 14 = 0.1 mm; 15 – 17 = 0.3 mm.

FIGURES 47 – 51. Trachelas odoreus sp. n., genitalia. 47 Epigynum, cleared ventral view; 48 Same, dorsal view; 49 Palp, prolateral view; 50 Same, retrolateral view; 51 Same, ventral view. Scale bars: 47, 48 = 0.1 mm; 49 – 51 = 0.2 mm.