Abstract
The genus Heleocoris in Indochina has languished for more than a century with no substantial history of taxonomic, biological, or ecological research since the original descriptions of the species, despite its abundance and ubiquity in streams throughout the region. This is largely because of the inability to assign specific identities to these insects and the need for taxonomic revision. Presented here is a comprehensive treatment on the taxonomy and faunistics of the four species now known to occurin Thailand, including the description of Heleocoris mcphersoni, n. sp. Diagnostic information, records from Thailand and other Southeast Asian countries, ecological notes, habitus photographs, and a taxonomic key to identify the four species are presented.
NSTL