Xystosomus laevimicans, Erwin, 1973

Erwin, Terry L., 1973, Studies of the subtribe Tachyina (Coleoptera: Carabidae: Bembidiini), Part I: A revision of the Neotropical genus Xystosomus Schaum, Smithsonian Contributions to Zoology 140, pp. 1-39 : 31-32

28. Xystosomus laevimicans , new species

FIGURES 59 , 64 , 72

TYPE-LOCALITY.— Alto da Serra , Sao Paulo, Brazil.

TYPE-SPECIMENS.—The holotype male and the allotype (from Santos, Brazil), are in BMNH. Both were collected by G. E. Bryant in 1912. Two paratypes, labelled same as the allotype: BMNH, 1; USNM, 1.

DESCRIPTION.— Form: As in X. laevis , except flatter and forebody narrower. Easily distinguished

by the form of the pronotum with its basally convergent sides.

Color: Rufous; pronotum and elytra slightly iridescent; appendages testaceous; antennae slightly infuscated apically.

Head: Broad between eyes; frontal furrows short, foviform, not prolonged beyond anterior supraorbital setigerous pore; eyes small, large-faceted, slightly prominent.

Pronotum ( Figure 59 ): Transverse (W/ L, x 1.74; range, 1.70-1.85, 4 specimens); subcordate with sides basally convergent; hind angles sharp, about 90°, sides anterior to angles slightly sinuate; lateral setigerous pores and laterobasal carinae absent; side margins beaded, not reflexed.

Elytra: Smooth; as in X. laevis except more prolonged apically.

Microsculpture: Dorsal surface of head, pronotum, and elytra with transversely stretched meshes.

Secondary sexual characters: Male genitalia (Figure 64) and female genitalia characteristic of the species group.

Size: Four specimens: length, 1.9-2.1 mm; width, 1.0-1.1 mm.

NATURAL HISTORY.— Unknown, except adults collected in March. No teneral specimens seen.

LOCALITY RECORDS ( Figure 72 ).—I have seen four specimens from the following localities:

SOUTH AMERICA: BRAZIL: Alto da Serra, Sao Paulo (BMNH); Santos (BMNH, USNM).

Figures

FIGURE 72.—Approximate range of the inflatus and laevis groups.

FIGURES 57-62.—Pronotum, dorsal aspect: 57, Xystosomus laevis, female, Nova Teutonia, Brazil; 58, X.paralaevis, female, Sao Paulo, Brazil; 59, X. laevimicans, female, Santos, Brazil; 60, X. niger, female, Serra Bocaina, Brazil; 61, X. tholus, male, Alto da Serra, Brazil; 62, X. turgidus, female, Rio Caraguata, Brazil.

FIGURES 63-68 Genitalia. 63-67, Male, left lateral aspect: 63, Xystosomus laevis, Nova Teutonia, Brazil; 64, X. laevimicans, Alto da Serra, Brazil; 65, X. impressifrons, Brazil; 66, X. tholns, Alto da Serra, Brazil; 67, X. niger, Serra Bocaina, Brazil. 68, Female, X. impressifrons, "Lagune de Sacuaresma," Brazil: a, bursa copulatrix; b, spermathecal reservoir.