Mastostethus mulier Rodríguez-Mirón 2019, sp. nov

Mastostethus mulier sp. nov. (Figs 1, 2, 3a) Type. Holotype (female): Mex. St. of Chiapas, 1.7 mi. N. Ixhuatan, 10-VII-65, 1700’, D. R. Paulson // Mastostethus sp., det R. White (FSCA). Differential diagnosis Mastostethus mulier sp. nov. is distinguished from M. duplocinctus Clark, 1866, by the following characters: Elytral lateral edge rounded, apex of pygidium rounded (Fig. 2b) and the spermathecal shape; spermathecal capsule boomerang-shaped, with velum; stem as long as proximal part of spermathecal capsule, with ornaments (Fig. 3a). Terminal portion coiled and notably long. In M. duplocinctus the elytral lateral edge is flattened, the apex of pygidium has a prominence; proximal part of spermathecal capsule is very elongated, without velum, the stem and terminal portion are shorted (Fig. 3b). Description. Length = 10.5 mm, width = 5.0 mm. Head, pronotum, prosternum, and metaventrite red; elytra yellow with one humeral and apical stripe and two spots in middle part; antennae, scutellum, tibiae and tarsi black, abdomen orange; femora red with black spot; inter-ocular space with a black spot, pronotum with five spots (Fig.1). Head: Occiput coarsely and densely punctate, inter-ocular space sparsely punctate; clypeus trapezoid, punctate with erect pubescence laterally, posterior region translucent; labrum semicircular, surface sparsely pubescent, edge densely pubescent; antennae reaching pronotal edge posteriorly, antennomeres I–IV subcylindrical with sparse long setae, V–XI strongly flattened and widened, densely pubescent (Fig. 1c). Thorax: Pronotum broader than long, trapezoidal, base wider than the anterior portion, pronotal disc slightly convex, punctures small, sparse, posterior angles slightly acute, posterior edge sinuate, with a ridge in the middle part and lateral depressions (Fig. 2a). Scutellum subtriangular, rounded at apex, sparsely punctate, pubescence short; elytral humeri truncate, projecting antero-laterally; elytra laterally slightly widened from humeri to posterior third, then convergent to suture, lateral edge rounded; disc convex, shiny, finely punctate and pubescent; metaventrite sparsely punctate and pubescent; metaepisternum with anterior portion concave, finely punctate and pubescent, posterior portion glabrous. Hind femora clavate, tibiae with erect pubescence; tibiae subcylidrical, with one dorsal row of denticles, hind tibiae curved slightly. Abdomen: Pygidium sparsely punctate and pubescent, apex rounded (Fig. 2b); last abdominal ventrite concave, apex sinuate (Fig. 2c). Spermatheca boomerang-shaped, proximal part of spermathecal capsule with velum. Stem as long as proximal part of spermathecal capsule, with ornaments, terminal portion coiled and notably long (Fig. 3a). Male. Unknown. Distribution. Mexico: Chiapas Etymology. The specific name is proposed because the only specimen of the species is a female; from the Latin mulier = woman.