Amphidraus cornipalpis Salgado & Ruiz 2019, sp. nov.

Amphidraus cornipalpis sp. nov.

Figs 1–6, 14

Type material. Holotype: Ƌ from Parque Nacional da Serra das Confusões, [09°10'31.4"S, 43°33'20.8"W], Guaribas, Piauí, Brazil, 15.XII.10, L.S. Carvalho et al. leg. (MPEG 35014). Paratypes: 1 ♀, same data as holotype [MPEG 35015]; 1♂ and 1♀ from Caruaru, [08°17'08.6"S, 35°58'06.7"W], Pernambuco, Brazil, 2009–2010, H.P. Amorim leg. [IBSP 160615 (♂), 160616 (♀)].

Etymology. The specific epithet is a compound adjective in Latin (cornus + palpus) and refers to the shape of distal process on the embolic disc (Fig. 3A).

Diagnosis. Males of Amphidraus cornipalpis sp. nov. share similarities with those of Amphidraus loxodontillus Salgado & Ruiz, 2017, both with an embolic disc with one poorly-sclerotized, distal lamella that covers part of dPED ventral view (white arrows in Figs 3 A–B). However, males of A. cornipalpis sp. nov. can be distinguished from those of A. loxodontillus by having a longer and acute distal process on embolic disc (dPED) with the tip curved distally (shaped like a cow horn) (Figs 2C, 3A, 5A, 5D, 6 D–E), whereas in A. loxodontillus the dPED is short and rounded (Fig. 3B; see also Salgado & Ruiz 2017: fig. 26C). In addition, A. cornipalpis sp. nov. has a reduced RTA (as large as RvTA in A. loxodontillus) and a small ITA in the male palp (Figs 5B, 5E), which is absent in A. loxodontillus (see Salgado & Ruiz 2017: figs 26B, 26D). Also, males of A. cornipalpis sp. nov. differ from those of all other species of Amphidraus by having a tubercle placed on proximal dorso-retrolateral portion of the cymbium (black arrows in Figs 2 C–F, 5A–B, 5E, 6C) (present also in Yacuitella nana Galiano, 1999). Females of A. cornipalpis sp. nov. are similar to those of Y. nana by the arrangement of copulatory ducts and spermathecae in the epigyne, but differ from that species by having more separate copulatory openings, longer copulatory ducts and no tubercle on the epigynal plate (Fig. 5F), which is medially placed in Y. nana (see Galiano 1999: figs 12–14).

Description. Male holotype (MPEG 35014). Total length: 3.33. Carapace 1.78 long, 1.23 wide and 0.89 high. Ocular quadrangle 0.83 long. Anterior eye row 1.25 wide, posterior 1.13 wide. Legs 4312. Length of leg: I 2.65 (0.83 + 1.00 + 0.82); II 2.54 (0.81 + 0.93 + 0.80); III 3.12 (1.01 + 1.09 + 1.02); IV 3.40 (0.97 + 1.19 + 1.24). Palp (Figs 2 C–F, 3A, 5A–E, 6A–E): femur with large and low bump on median-ventral portion (Fig. 5C); patella with no modifications; tibia with a prolateral rounded expansion and a ventro-distal depression (Figs 2 D–F, 5A, 5E, 6A); large RvTA with acute tip (Figs 2D, 5B, 6C); short, poorly-sclerotized ITA retrolaterally projected (Figs 2F, 5E, 6C); cymbium oval (Figs 2F, 5E), with conductor (cc) wider than long with sinuous proximal border (Figs 2E, 6 A–B); tegulum with slender lobe curved to prolateral side (Figs 2C, 3A, 5A, 5D); embolus shaft (e) with tip strongly curved to retrolateral side (Figs 2C, 3A, 5A); embolic filament (ef) longer than embolus shaft (Figs 3A, 5A, 5D). Color in alcohol (Figs 1, 2 A–B): cephalic area black; thoracic area light brown with a black procurved arc; chelicera light brown; palp light brown, with black mark ventrally on femur and with dark brown cymbium; mouthparts and sternum light brown; abdomen dorsally and ventrally light brown variegated with dark brown; legs light brown with a distal black ring on metatarsi III and two black rings on metatarsi IV, one proximal and another distal.

Female paratype (MPEG 35015). Total length: 3.77. Carapace 1.66 long, 1.15 wide and 0.81 high. Ocular quadrangle 0.80 long. Anterior eye row 1.13 wide, posterior 1.00 wide. Legs 4312. Length of leg: I 2.54 (0.83 + 1.00 + 0.71); II 2.25 (0.73 + 0.88 + 0.64); III 3.08 (1.05 + 1.05 + 0.98); IV 3.55 (1.08 + 1.23 + 1.24). Epigyne/vulva (Figs 4C, 5F): epigynal plate with posterior border slightly bilobed; copulatory openings separated by approximately two diameters of copulatory ducts; long and convoluted copulatory ducts, forming a pair of rounded masses with spermathecae; oval spermathecae diagonally projected; fertilization ducts anteriorly placed and laterally projected. Color in alcohol (Figs 4 A–B): cephalic area black; thoracic area dorso-laterally dark brown and centrally light brown; abdomen dorsally and laterally variegated with brown; ventrally pale; pale legs with black spots, being more intense on metatarsi III and IV (same pattern as in male).

Distribution. Known from the states of Pernambuco and Piauí (Brazil) (Fig. 14).