Comprehensive Description
(
Anglèis
)
fornì da Smithsonian Contributions to Zoology
Xystosomus sculpticollis Bates
Xystosomus sculpticollis Bates, 1871b:266. [Lectotype, male, MHNP, here selected. Type-locality: Ega (Teffé), Brazil.]
DESCRIPTION.—Form: As in X. strigosus, but easily distinguished from that species and all other species of the group by the longitudinal carinae of the pronotal disc.
Color: Head and body rufopiceous, elytra slightly iridescent, appendages testaceous.
Head: Narrow between eyes; frontal furrows moderately impressed with sharp carinae lateral to them near eye margin; eyes large and prominent.
Pronotum (Figure 11): Quadrate (W/L, 1.46; range, 1.39–1.58; 3 specimens), only slightly wider than head across eyes; disc with six longitudinal carinae, each separated from the other by deep sulci; hind angles about 90°, sides anterior to angles straight to about middle; side margins broadly explanate in basal half, narrowly explanate in apical half.
Elytra: Striae 1–8 of each elytron well impressed and punctate, entire though less impressed at apex; punctures large and well impressed, more so laterally, each contiguous with the next by a shallowly impressed stria, at least in basal half; recurrent groove doubled back into a hook, deeply impressed; chaetotaxy as in X. gruti; plica well developed externally, short.
Microsculpture: As in X. gruti.
Secondary sexual characters: Male genitalia characteristic of the species group (Figure 28). Female genitalia characteristic of the species group.
Size: Three specimens: length, 3.3–3.6 mm; width, 1.6–1.8 mm.
NATURAL HISTORY.—Unknown, except that the specimen from Teffé was collected in the “1st quarter of 1879.” No teneral specimens seen.
LOCALITY RECORDS (Figure 69).—I have seen four specimens from the following localities:
SOUTH AMERICA: BRAZIL: Amazonas Province: São Paulo d’Olivença (MHNP); Teffé (Ega) (MHNP).
