Hydrops triangularis (Wagler in Spix, 1824)

Type locality. Lago Tefé, Rio Amazonas, Tefé, state of Amazonas, Brazil .

Distribution. Widespread in the northern portion of South America, in Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname, Trinidad, and Venezuela, in Amazonian forests (Plt. 292A). In Brazil, recorded widely in Amazonia and marginally in the Cerrado (Plt. 292A) at low elevations (Plt. 292B). Observed in the field in lakes, rivers, and flooded forest and savanna (Scartozzoni, 2010; von May et al., 2019).