Sparianthis boibumba spec. nov.

Figs 1A–E, 2A–D, 20

Type material: Holotype: ♂, BRAZIL: Amazonas: Manaus [03º06’S, 60º01’W], February 1979, J.A. Rafael leg. (IBSP 344621).

Etymology. The specific name refers to a Brazilian folklore festival, very popular in Manaus, with human and fantastic animal characters, which revolves around a legend about the death and resurrection of a bull; noun in apposition.

Diagnosis. Males of S. boibumba spec. nov. are distinguished from all congeners by the dRTA long (tip surpassing the margin of the alveolus), finger-like with tip ventrad, and cymbium with triangular, pointed retrobasal process (Figs 1D–E, 2B–C) (dRTA shorter, not surpassing posterior margin of alveolus, and cymbium smooth or with small, rounded retrobasal process in the other species). Females are unknown.

Description. Male (holotype): Prosoma and chelicerae pale brown; legs and pedipalps slightly lighter than prosoma; labium brown, distally yellowish brown; endites pale orange, distally pale yellow; sternum pale yellowish brown with pale brown margins; opisthosoma pale brownish gray with no distinct pattern; pair of elongated Vshaped lines of muscular impressions medially along entire ventral surface; spinnerets pale brownish gray (Figs 1A–B). Total length 9.3. Prosoma: 3.8 long, 3.1 wide. Opisthosoma: 5.0 long, 2.4 wide. Eyes: diameters: 0.25, 0.20, 0.14, 0.18; interdistances: 0.18, 0.05, 0.40, 0.21, 0.16, 0.05. Legs: I: 13.4 (3.7, 1.8, 3.6, 3.5, 0.8); II: 13.6 (3.9, 1.9, 3.4, 3.6, 0.8); III: - (3.1, 1.5, 2.2, 2.4, absent); IV: 12.5 (3.5, 1.4, 2.8, 3.7, 1.1). Spination follows the generic pattern except tibiae I–II: d0-1-0; metatarsus III: p1-1-1; r1-1-1. Palp: tibia slightly longer than half cymbium length with pair of prolateral spines (tips not surpassing the margin of the alveolus); mRTA triangular, pointed (in retrolateral view), arising at base of dRTA; vRTA slightly longer than wide, with rounded tip, translucid; ST visible retrolaterally between 4–6 o’clock; TBC short, keel-like, slightly projecting distally at retrolateral end; TBE gutter-shaped, almost as long as embolus; MA partly hyaline, indented medially at margin; embolus with long ventral keel along most of its length and short, fin-like dorsal keel at tip (Figs 1C–E, 2A–D).

Female: Unknown.

Distribution. Only known from the type locality (Fig. 20).