Rhymbomicrus Casey, 1916: 139 .
Type species: Alexia lobata LeConte & Horn, 1883 . Micropsephellus Arrow, 1920: 79 .
American genus with 5 known species: 3 from eastern United States, one from Lesser Antilles and one from México, and Central America (Pakaluk 1987) . Most specimens have been collected in forest litter or under bark (Pakaluk 1987).
9. R. hemisphaericus (Champion, 1913) Fig. 18.
Micropsephus hemisphaericus Champion, 1913: 118 .
Micropsephellus hemisphaericus: Arrow 1920: 80; Blackwelder 1945: 437. Rhymbomicrus hemisphaericus: Strohecker 1953: 17 .
Type locality: not designated.
Type material: syntypes in BMNH.
Distribution: México, Guatemala, Nicaragua.