Xystosomus inflatus (Schaum), 1859

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 : 28

24. Xystosomus inflatus (Schaum)

FICURES 52, 54, 55, 72

Tachys inflatus Schaum, 1859:202 . [ Lectotype, here selected, a female, in HUB. Type-locality: "Neufreiburg" (Nova Friburgo), Brazil .]

DESCRIPTION.—Form: Short and broad, highly convex, and with a small depressed head. Easily distinguished from the other species of the group by the well-developed laterobasal carinae of the pronotum and the deep triangular fova formed medial to the carina.

Color: Piceous, very shiny; appendages testaceous; antennal articles apically and femora slightly infuscated.

Head: Narrow between eyes; frontal furrows short, arcuate, ended at anterior supraorbital setigerous pore; frons with two deeply impressed fovae each side of midline; eyes depressed, medium-

sized, and prominent.

Pronotum ( Figure 52 ): Broadly transverse (W/L, x 1.74; range 1.72-1.83; 7 specimens); lateral setigerous pores present just anterior to middle and at hind angles; laterobasal carinae well developed; hind angles obtuse, sides anterior to angles slightly arcuate; side margins beaded.

Elytra: Smooth, side margins narrowly reflexed; humeral projection absent, humerus evenly rounded or slightly concave posteriorly; chaetotaxy as in X laevis ; plica very small, evident externally.

Microsculpture: Frons with transversely stretched meshes; absent from pronotum and elytra.

Secondary sexual characters: Male genitalia (Figure 54) and female genitalia ( Figure 55 ) characteristic of the inflatus group.

Size: Eight specimens: length, 2.4—2.9 mm; width, 1.3-1.5 mm.

NATURAL HISTORY.— Unknown, except adults collected in September, April, and May. No teneral specimens seen.

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

SOUTH AMERICA: BRAZIL: Rio de Janeiro Province: Nova Friburgo (MHNP); Rio de Janeiro (MHNP). Minas Gerais Province: Caraca (MHNP).

Figures

FIGURE 55.—Female genitalia, ventral aspect, with spermathecal reservoir, of Xystosomus inflatus, Nova Friburgo, Brazil.

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

FIGURES 52, 53.—Pronotum, dorsal aspect: 52, Xystosomus inflatus, male, Caraca, Brazil; 53, X. convexus, female, Minas, Brazil.