Nieser reunió las especies de chinches acuáticas incluidas por Lauck en los grupos Belostoma plebejum y Belostoma pygmeum en un solo grupo, Belostoma plebejum, criterio que se sigue en este trabajo. El grupo incluye siete especies pequeñas que presentan el divertículo ventral de los genitales masculinos recurvado ventrad: Belostoma lariversi De Carlo, 1969; B. micantulum (Stål, 1858); B. plebejum (Stål, 1858); B. pygmeum (Dufour, 1863); B. minusculum (Uhler, 1884), las cuales se redescriben e ilustran y B. parvum registrada de Venezuela, Colombia, Guyana, Suriname y Brazil y B. nicaeum registrada de Manaus, Brasil. Las dos especies nuevas que se describen e ilustran.

Nieser gathered the water bug species included by Lauck in the groups Belostoma pygmeum and Belostoma plebejum in a single group, Belostoma plebejum. We follow this criterion and use the terminology used by Estévez and Polhemus for species descriptions. The Belostoma plebejum group includes seven small species with the ventral diverticulum of male genitalia recurved ventrad: Belostoma lariversi De Carlo, 1969; B. micantulum (Stål, 1858); B. plebejum (Stål, 1858); B. pygmeum (Dufour, 1863); B. minusculum (Uhler, 1884). B. parvum sp. nov. from Venezuela, Colombia, Guyana, Suriname and Brazil, and B. nicaeum sp. nov. from Manaus, Brazil. The two new species are described and illustrated, and new synonymies are proposed. Rev. Biol. Trop. 55 (1): 147-155. Epub 2007 March. 31.

A key to species groups of the genus Belostoma Latreille, 1807, using new taxonomic characters are presented as well as the revision of the four species included in the denticolle group: B. denticolle Montandon, 1903, and three new species: B. orbiculatum from eastern Argentina and southern Brazil, B. retusum from eastern Argentina and B. amazonum from northern Brazil which are described and illustrated.