Comprehensive Description
(
Anglèis
)
fornì da Smithsonian Contributions to Zoology
Xystosomus iris
TYPE-LOCALITY.—Monson Valley, Tingo Maria, Peru.
TYPE-SPECIMENS.—The holotype male and allotype are in CAS. Both were collected by Schlinger and Ross in 1954. Four paratypes from Bolivia: MHNP, 2; USNM, 2.
DESCRIPTION.—Form: As in X. strigosus, except pronotum much narrower. Narrowest species in the group in relation to head width. Easily distinguished from all species of the group by the doubled back recurrent groove which forms a large loop.
Color: Head and body rufopiceous; pronotum and elytra with slight metallic green luster; elytra also strongly iridescent; appendages testaceous; antennae slightly infuscated apically.
Head: Narrow between eyes; frontal furrows moderately impressed; eyes large and prominent.
Pronotum (Figure 10): Quadrate (W/L, 1.46; range, 1.44–1.57; 6 specimens), only slightly wider than head across eyes; hind angles about 90°, side margins anterior to angles slightly sinuate; side margins narrowly explanate basally, beaded anteriorly.
Elytra: Striae 1–8 of each elytron well impressed and punctulate; punctures moderately large and separated by about twice their own diameter; recurrent groove doubled back into a deeply impressed elliptical loop; humeral projection well developed, sharply acute (oblique view); chaetotaxy as in X. gruti; plica short, evident externally.
Microsculpture: As in X. gruti.
Secondary sexual characters: Male genitalia (Figure 27) and female genitalia characteristic of the species group.
Size: Six specimens: length, 3.0–3.6 mm; width, 1.4–1.7 mm.
NATURAL HISTORY.—Unknown, except adults collected in March (Bolivia) and October (Peru). No teneral specimens seen.
LOCALITY RECORDS (Figure 69).—I have seen six specimens from the following localities:
SOUTH AMERICA: BOLIVIA: Cochabamba (MHNP); Cachuela Esperanza (USNM). PERU: Monson Valley, Tingo María (CAS).
