Xystosomus sublaevis Bates, 1882

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 : 14-18

10. Xystosomus sublaevis Bates

FIGURES 15 , 32 , 69

Xystosomus sublaevis Bates, 1882:146 . [Lectotype, female,

BMNH, here selected. Eleven paralectotypes, labelled by

me: BMNH, 8; MHNP, 3. Type-locality: Volcan de Chi-

riqui, Panama.]

DESCRIPTION.—Form: As in X. gruti , except elytra more convex and shorter. The members of this species are not easily distinguished from other members of the "smooth elytra-convex interval" group of species on any one character state. Members of X. sublaevis are without the sinuate pronotal sides of X. anterocostis , without the coarsely punctate elytral rows of X. batesi , without the highly convex lateral intervals of X. sulcicostis , with some traces of striae or serial punctures, and therefore not like X. aetholius .

Color: Head and body dark rufopiceous, shiny; pronotum and elytra slightly iridescent; appendages testaceous.

Head: Broad between eyes; frontal furrows short and sulcate; eyes large and prominent.

Pronotum ( Figure 15 ): Transverse (W / L, x

1.58; range, 1.47-1.66; 9 specimens), otherwise as in X. gruti .

Elytra: Striae 5-8 faintly impressed and punctulate; intervals slightly convex; disc with four rows of faintly impressed punctulae, each separated from the other by several times its own diameter; interstices between serial punctures striate or not; side margins broadly explanate; chaetotaxy as in X. gruti; plica small, evident externally.

Microsculpture: As in X. gruti .

Secondary sexual characters: Male genitalia ( Figure 32 ) and female genitalia characteristic of the species group.

Size: Nine specimens: length, 3.0-3.5 mm; width, 1.4-1.6 mm.

NATURAL HISTORY.—The specimen from Costa Rica was collected in April at 250 meters elevation. The original series of Bates was collected in Panama at 800 to 4,000 feet (244 to 1,220 m) elevation, but no date was recorded. No teneral specimens were seen.

LOCALITY RECORDS ( Figure 69 ).—I have seen 16 specimens from the following localities:

CENTRAL AMERICA: COSTA RICA: Rio Banano (USNM). PANAMA: Bugaba (BMNH, MHNP); Volcan de ChiriquI (BMNH, MHNP).

Figures

FIGURE 69.—Approximate range of the gruti group.

FIGURES 7-21.—Pronotum, dorsal aspect: 7, Xystosomus ampliatus, female, Hamburg Farm, Costa Rica; 8, X. nigripalpis, female, Barro Colorado Island, Panama; 9, X. strigosus, female, Rio Parahyba, Brazil; 10, X. iris, female, Cochabamba, Bolivia; 11, X. sculpticollis, female, Teffe, Brazil; 12, X. negrei, male, Rancho Grande, Venezuela; 13, X. aetholius, female, Cochabamba, Bolivia; 14, X. anterocostis, Hamburg Farm, Costa Rica; 15, X. sublaevis, male, Rio Banano, Costa Rica; 16, X. sulcicostis, female, Volcan de Chiriqu!, Panama; 17, X. apicisulcatus, female, Minas, Brazil; 18, X. batesi, female, Petr6polis, Brazil; 19, X. seriatus, female, Nova Teutonia, Brazil; 20, X. ovatulus, female, Caraca, Brazil; 21, X. grossipunctatus, female, Caraca, Brazil.

FIGURES 31-35.—Male genitalia, left lateral aspect, of five species of the gruti group: 31, Xysto- somus anterocostis, Hamburg Farm, Costa Rica; 32, X. sublaevis, Volcan de Chiriqui, Panama; 33, X. sulcicostis, Volcan de Chiriqui, Panama; 34, X. seriatus, Nova Teutonia, Brazil; 35, X. ovatulus, Nova Friburgo, Brazil.