Protimesius jirau, Bragagnolo, Cibele, 2013

Bragagnolo, Cibele, 2013, Two new species of Protimesius from northern Brazil (Opiliones: Laniatores: Stygnidae), Zootaxa 3620 (2), pp. 283-292 : 288-289

Protimesius jirau sp. nov.

( Figs. 3 A–I; 4D–F)

Types data: Brazil, Rondonia state, Porto Velho (Caiçara), 27.II.2010, M.C. Silveira leg. [3 holotype (MZSP 33199), paratypes (MZSP 33119, 2Ƥ 23; MNRJ 0 7215, 1Ƥ 13)].

Etymology. The specific name “ jirau ”, a noun in apposition, originates from the Tupi language and makes reference to the “ Jirau Hydroelectric Station”, locality where the species was collected.

Diagnosis: This species is similar to P. c ir io Villareal-Manzanilla & Pinto-da-Rocha and P. laevis (Sorensen, 1932) by the presence of a large, pointed, dorso-apical apophysis on male trochanter IV. It differs from the others species of Protimesius due to the absence of a ventral row of tubercles on male femur IV—present in all species of the genus except P. longipalpis and P. a p i a c a s — and the presence of a ventrobasal curved apophysis on femur IV.

Description of male (holotype MZSP 33199): Measurements: Dorsal scute length 4.7; prosoma length 2.1; dorsal scute width 3.85; prosoma width 3.8; interocular distance 2.3.

Dorsum ( Fig. 3 A, B). Prosoma: anterior margin smooth, with low anterior eminence with two tubercles. Ocularium and lateral margin smooth. Area I divided, smooth. Area II smooth. Area III with two high parallel spiniform apophysis. Posterior margin straight and smooth; free tergites I–III smooth.

Venter: Coxa I with a median row of four tubercles; II with a median row of five tubercles, two apical; III and IV irregularly and minutely tuberculated. Free sternites I–III with a row of minute granules. Anal plate covered irregularly with minute granules.

Chelicera: Swollen. Segments I–II smooth; III with two distal teeth.

Pedipalpus ( Fig. 3 H, I). Coxa with large dorso-basal apophysis and three pointed tubercles; ventral with three pointed tubercles. Trochanter with one ventral tubercle. Femur with one ventro-basal tubercle. Patella unarmed. Tibia mesal IIiIi, ectal IIiIi; Tarsus mesal IiIiIi; ectal IiiIi.

Legs ( Fig. 3 C–G): Coxa I with two dorsal tubercles; II with two dorsal tubercles, one anterior and one larger, posterior; III with one dorsal apical tubercle; IV dorsally minutely tuberculated. Trochanter I–III smooth, IV with two ventral tubercles and one pointed dorso-apical apophysis. Femora I–III smooth, IV with a ventro-basal curved apophysis and a basal retrolateral row of seven tubercles. Patella IV with a pointed ventro-apical apophysis. Tibia IV with one retrolateral row with nine tubercles on distal 2/3; one bifid prolateral and one large retrolateral apical apophysis. Tarsal segmentation: 8:20:7:8.

Penis ( Fig. 4 D–F): ventral plate with lateral and distal margin straight, with three distal pairs of long curved setae and one intermediary short pair; six basal pairs of setae; dorsal process present; stylus serrate apically.

Color: In alcohol mostly yellowish brown, apophyses of area III dark brown.

Female (Paratype MZSP 33119): Measurements: Dorsal scute length 4.7; prosoma length 2.0; dorsal scute width 4.0; prosoma width 3.5; interocular distance 2.0.

Similar to male, except for: Chelicera not swollen; prosoma without low anterior eminence. Pedipalpal tibia mesal IiiIi, ectal IIiIi; tarsus mesal IiIiIi, ectal Iiii. Legs finely granular; femur IV smooth.

Distribution: Known only for the type-locality.

Figures

FIGURE 3. Protimesius jirau sp. nov., male holotype. A. Dorsal view of body. B Lateral view of body. C – G. Segments of leg IV (C. dorsal view of trochanter-tibia, D. ventral view of trochanter-tibia; E. ventral view of trochanter – femur; F. ventral view of patela; G. ventral view of tibia;); H and I. Right pedipalpus (H. ectal view, I. mesal view). Scale bars: 1 mm.

FIGURE 4. Distal portion of penis. A – C. Protimesius regalo sp. nov., male holotype (A. dorsal view; B. ventral view; C. lateral view. D – F. Protimesius jirau, sp. nov., male holotype (D. dorsal view; E. ventral view; F. lateral view) Scale bars: 0.1 mm.