Soesilarishius trombetas sp. nov.

Figs 21‒28

Types. Holotype: Ƌ from Rio Acapu, Floresta Estadual do Trombetas, Oriximiná, Pará, Brazil, 01°07'51.60"S, 56°24'59.40"W, 10–18.X.2014, leg. M.B. Aguiar-Neto et al. (MPEG 32015). Paratypes: 1 Ƌ (INPA) and 1 ♀ (MPEG 32016), same data as holotype.

Etymology. The epithet in apposition is a toponomy after the type locality.

Diagnosis. The male is similar to those of S. aurifrons (Taczanowski, 1878), S. micaceus, S. paxiuba, S. muiratinga, S. cearensis Ruiz, 2013, S. bicrescens Ruiz, 2013 and S. laticlavus sp. nov. by having the embolus arising from the median portion of the prolateral bulb (Fig. 25). It can be distinguished from those of S. muiratinga and S. laticlavus sp. nov. by the slender RTA (Fig. 26); from those of S. cearensis and S. bicrescens by the initial portion of the embolus extending laterally (Fig. 25), not proximally; and from those of S. aurifrons and S. paxiuba by the blade-like tip of the embolus, with the median portion membranous (Fig. 25) (slender in the other two; see Ruiz 2011: fig. 1; Ruiz 2013: fig. 25). The female is similar to that of S. macrochelis Ruiz, 2013 for the simple, short internal duct with no obvious glandular structure, but can be distinguished by the lateral coupling pockets advanced on the epigynal plate and the unmodified spermatheca (Fig. 28); it is also superficially similar to that of S. crispiventer Ruiz, 2011 by the position of the copulatory openings, but can be distinguished by the position of the coupling pockets.

Description. Male holotype (MPEG 32015). Total length: 2.90. Carapace dark brown, shiny, with cephalic region black (Fig. 21); 1.57 long, 1.19 wide, 0.90 high. Ocular quadrangle 0.78 long; anterior eye row 1.16 wide, posterior 1.05 wide. Chelicera, labium and sternum dark brown (Fig. 22). Palp brown, with small projection on distal prolateral part of tibia. Legs 1342; I: femur, patella, tibia and metatarsus brown, tarsus bright yellow; II‒III: femora, patellae and tibiae brown, metatarsi and tarsi yellow; IV as I, with paler tarsus (Fig. 22). Length of leg I 3.09 (1.07 + 1.21 + 0.81); II 2.50 (0.81 + 0.93 + 0.76); III 3.06 (0.95 + 1.14 + 0.97); IV 2.83 (0.83 + 0.93 + 1.07). Abdomen dorsally dark brown with proximal pair of tufts of white scales and another pair on posterior half (Fig. 21); dark brown ventrally (Fig. 22). Spinnerets dark brown.

Female paratype (MPEG 32016). Total length: 3.23. Carapace dark brown, with metallic bluish sheen and tuft of white scales on central region; cephalic region black (Fig. 23); 1.69 long, 1.12 wide, 0.78 high. Ocular quadrangle 0.81 long; anterior eye row 1.12 wide, posterior 0.97 wide. Chelicera, labium, endite and sternum light brown (Fig. 24). Palp yellow. Legs 1342; I‒IV yellow. Length of leg I 2.85 (0.90 + 1.14 + 0.81); II 2.35 (0.74 + 0.90 + 0.71); III 2.83 (0.88 + 1.00 + 0.95); IV 2.78 (0.83 + 0.88 + 1.07). Abdomen as in male, lighter, with light areas covered with white scales (Fig. 23); yellow ventrally (Fig. 24). Epigyne externally with anterior semicircular copulatory openings and inconspicuous lateral coupling pockets (Fig. 27); internally with simple ducts leading to medial fertilization ducts (Fig. 28). Spinnerets yellow.

Note. Male-female matching was established based on co-occurrence and low abundance. It is possible, though, that this female does not belong with this male, or even that it is a theratological specimen. However, the epigyne has all the structures expected to be present in a functional piece (copulatory openings and ducts, fertilization ducts and even coupling pockets). Hence, we take the chance to describe this female as the possible female of this species.

Distribution. Known only from the type locality (Brazil, Pará).