Oxysoma itambezinho Ramírez

Ramírez, Martín J., Ansaldi, María Julieta & Puglisi, Alejandro F., 2004, Description of the females of Oxysoma itambezinho Ramírez and Monapia tandil Ramírez, and their effects on the generic relationships of Gayennini (Araneae, Anyphaenidae, Amaurobioidinae), Zootaxa 668, pp. 1-8 : 5-6

Oxysoma itambezinho Ramírez

( Figs. 5–7 )

Oxysoma itambezinho Ramirez, 2003: 225 (male holotype from Itaimbézinho, Cambará do Sul, Rio Grande do Sul, Brazil, deposited in MCTP 1653, not re­examined).

Note: The female was identified by the presence of an anterior spine on the chelicerae, and its occurrence in sympatry with a male of O. itambezinho . These specimens originate from Itatiaia, Rio de Janeiro state, approximately 900 kilometers from the type locality in Rio Grande do Sul. Both localities are part of the Brazilian Atlantic Highlands.

Diagnosis: The female of O. itambezinho resembles those of some Tasata , Oxysoma and Monapia species in the presence of a pale, elongate body and a pattern of small dark dots, but can be distinguished by the combination of a strong spine on the anterior face of the chelicerae and by the characteristic course of the copulatory ducts ( Fig. 7 ).

Description of female: Total length 9.37. Carapace length 3.80, width 2.42. Eyes, AME 0.10, ALE 0.18, PME 0.14, PLE 0.16. Chelicerae small with an anterior spine close to the base, three teeth on promargin, two on retromargin. Sternum length 2.12, width 1.28. Legs long and thin, length of tibia/metatarsus: I, 4.72/3.84, II, 4.64/3.76, III, missing, IV 4.85/4.60. Spines: Leg I, femur d 1­1­1, p and r 0­d1­d1; tibia v 2­2 ­2, p and r 1­1; metatarsus v 2 bas, p and r 0­1­0­1, d 0­p1­ 2. II, femur d 1­1­1, p 0­d1­d1­d1, r 0­d1­d1; tibia v 2­ 2 ­2, p d1­d1, r 0­1; metatarsus v 2 bas, p 1­0, r 0­1­0­1, d 0­p1­0­ 2. III, missing. IV, femur d 1­1­1, p d1ap, r 0­d1­d1; tibia v 2­2 ­2, p and r 1­1, d r1­0­1­0; metatarsus v 2­2 ­1, p and r d1­1­1, d 0­p1­2. Abdomen length 5.82, width: 1.94, distance spiracle­epigastrium 2.20, spiracle­spinnerets 1.52. Color ( Fig. 5 ): Light brown with brownish pattern on carapace. Abdomen pale with dark dots and a few dark spots. Legs yellowish­brown with some dark spots and dots. Sternum pale. Venter pale with a few dark dots, line of small dark spots at each side, from epigastrium to tracheal spiracle and at the end of the abdomen. Epigynum ( Figs. 6–7 ): Anterior pouch small, lateral lobes separated. Median field not depressed. Copulatory ducts thin and sinuous. Spermathecae spherical.

Material examined: BRAZIL: Rio de Janeiro: Itatiaia, no date, Ricoleta Silva ( MNRJ 41481), labeled “ Gayenna micropunctata M. L.”, presumably by Mello­Leitão.

Figures

FIGURES 5 – 7. Female of Oxysoma itambezinho Ramírez. 5, body, dorsal view; 6, epigyne, ventral view; 7, cleared epigyne, ventral view. (AB = accessory bulb [= “ head of spermatheca ”]; Apmf = anterior pouch of the medi­ an field; DP = “ dictynoid ” pore; FD = fertilization duct; S = spermatheca). Scales: 5 = 2 mm; 6 – 7: = 0.1 mm.