Amphidraus nigrigenu, Ruiz, 2017

Ruiz, Gustavo R. S., 2017, Ten new species of Amphidraus Simon, 1900 (Araneae: Salticidae: Euophryini) and three new combinations, Zootaxa 4312 (3), pp. 401-437 : 414

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Amphidraus nigrigenu

sp. nov.

Amphidraus nigrigenu sp. nov.

Figs 11–12 View FIGURE 11 View FIGURE 12

Type material. Holotype: ♂ from Juruti , 02°30'27.4"S, 56°10'39.5"W, Pará, Brazil, 17–21.XII.2012, A.S. Alves et al. leg. ( MPEG 32688 View Materials ). GoogleMaps

Etymology. A composed Latin noun (nigri + genu), meaning “black-knee”, in reference to the dark markings on the middle portion of the legs.

Diagnosis. The embolic disc and embolus of A. nigrigenu sp. nov. are similar to those of A. duckei , A. santanae , A. colombianus and A. simplex sp. nov.: there are two dPED and the vPED is proximal and projects retrolaterally; also, the embolus is thicker and sickle-shaped in these species ( Fig. 12 View FIGURE 12 C). However, A. nigrigenu sp. nov. can be distinguished by the short and rounded RvTA with two teeth on the border ( Fig. 12 View FIGURE 12 D), being slender and sinuous in A. duckei and A. colombianus , short with one tooth in A. santanae (see Galiano 1967: fig. 4), and finger-shaped in A. simplex sp. nov. ( Fig 14 View FIGURE 14 D).

Description. Male holotype ( MPEG 32688). Total length: 2.93. Carapace 1.44 long, 1.03 wide and 0.80 high. Ocular quadrangle 0.57 long. Anterior eye row 1.10 wide, posterior 0.91 wide. Legs: 3412. Length of leg I 2.20 (0.72 + 0.76 + 0.72); II 2.16 (0.72 + 0.76 + 0.68); III 2.96 (0.95 + 0.95 + 1.06); IV 2.92 (0.87 + 0.95 + 1.10). Palp ( Figs 12 View FIGURE 12 A–D): femur with subproximal ventral projection ( Figs 12 View FIGURE 12 A, 12D); tibia with reduced RTA and depression below the apophyses ( Figs 12 View FIGURE 12 B, 12D); embolic filament longer than straight, sclerotized portion ( Fig. 12 View FIGURE 12 C). Color in alcohol: thoracic area brown and cephalic area black; abdomen dorsally almost black; ventrally pale; legs with dark spots ( Figs 11 View FIGURE 11 A, 11B).

Female. Unknown.

Distribution. Known only from the type locality ( Brazil, Pará) ( Fig. 31 View FIGURE 31 ).

Note. Although we have found large variation in male palp structure of A. santanae , which could include the palp of the holotype of A. nigrigenu , we preferred to recognize this male as a different species, since the unusual morphology of the palp is accompanied by a different color pattern in legs and palps (black).


Museu Paraense Emilio Goeldi