Rhyssemus mexicanus Hinton 1934

Rhyssemus mexicanus Hinton

Rhyssemus mexicanus Hinton 1934:29.—Blackwelder, 1944: 216.

MALE.—Length 2.9 mm, greatest width 1.3 mm. Elongate, nearly parallel sided. Color dark reddish brown except front and clypeus, prosternum, legs and abdomen lighter reddish brown. Head finely, evenly tuberculate except a large, slightly oblique tubercle on each side of middle of vertex; anterior clypeal margin distinctly marginate between angulate angles, feebly reflexed. Pronotum 0.9 mm long by 1.2 mm wide; closely, densely tuberculate except 4 distinct, transverse ridges somewhat smooth, posterior 2 ridges broken medially (Figure 7); lateral and basal borders narrowly margined, with fringe of closely spaced, flattened setae. Elytra 2.0 mm long, 1.3 mm wide, humerus feebly dentate; striae extremely deeply impressed, punctured, punctures separated by 1 to 1 1/2 times their diameter; interval flat with a median row of large, closely spaced, acute tubercles and an inner row of very small tubercles on inner margin (Figure 7). Mesosternum alutaceous, with carinae strong between coxae, finer from coxae to anterior margin. Metasternal midline deeply impressed, complete, broadly foveate medially; surface shiny, roughened, becoming scabrous laterally. Abdominal sterna strongly alutaceous, with fluting along anterior margin of each sternum and a row of indistinct tubercles extending from lateral border nearly to midline; 4th sternum very strongly contracted medially. Pygidium roughly scabrous, tuberculate, 2 erect, apical setae present. Fore tibia smooth, with 3 lateral teeth, the posterior tooth at middle of tibia; spur long, robust, slightly curved downward apically. Middle and hind tibiae equal in length to femora, each apex fringed with short, unequal setae and 2 spurs, outer spur short, sinuate, apex curved, less than half as long as inner spur, inner spur longer than first tarsal segment, slightly sinuate. Hind tarsus shorter than tibia, basal segment as long as segments 2–4 combined, segments 2–4 subequal in length, 5th segment almost twice as long as 4th. Genitalia with lateral lobe thickened at apex, abruptly curved downward; internal sac lined with minute spicules, and 2 elongate, apically hooked sclerites (Figure 23).

FEMALE.—Similar to male except the pygidium is wider and the penultimate abdominal sternum slightly longer at middle.

VARIATION.—Length 2.8 to 2.9 mm, width 1.2 to 1.3 mm.

Type-Locality.—Temascaltepec, Tejupilco, Mexico.

TYPE DEPOSITORY.—Type 3814, California Academy of Sciences.