Abstract
The previously monotypic genus Sacosternum Hansen, 1989 is revised and redefined. Eleven species are recognized, of which eight are described as new: Sacosternum auribleps sp. n. (Brazil), S. cruciphallus sp. n. (Panama), S. delta sp. n.(Brazil, Paraguay); S. emissarium sp. n. (Costa Rica), S. epulum sp. n. (Brazil), S. garciai sp. n. (Costa Rica, Panama, Venezuela); S. inconnivum sp. n. (Costa Rica, Panama), and S. lebbinorum sp. n. (French Guiana, Peru, Brazil).
Sacosternum megalopus Hansen, 1989 is newly recorded from Costa Rica. Two species, referred to as Sacosternum sp.
A (Peru) and S. sp. B (Costa Rica) are left undescribed pending on the collecting of males.
Additional unidentified specimens are recorded from Mexico (Veracruz State), Guatemala, Costa Rica, Panama, and Venezuela. A key to known species of the genus is provided, important characters are illustrated.
A reconstruction of the phylogenetic relationships of Sacosternum species is performed, based on 51 adult morphological characters.