Hexacylloepus

Distinguished from other elmid genera by the combination of six visible abdominal ventrites and specific tarsal segment reductions, as indicated by the genus name. Detailed species-level identification requires examination of male genitalia and other fine morphological characters.

Associated with lotic freshwater systems, particularly riffle zones of streams and rivers. Larvae are aquatic and require well-oxygenated water with rocky or gravel substrates.

Recorded from multiple departments across Colombia including Amazonas, Antioquia, Boyacá, Caquetá, Casanare, Chocó, Huila, La Guajira, Meta, Putumayo, Tolima, Valle del Cauca, and Vaupés. Distribution likely extends to other Neotropical regions, though confirmed records are limited.

Complete metamorphosis with egg, larval, pupal, and adult stages. Larvae are fully aquatic, while adults are semi-aquatic or riparian, capable of remaining submerged using plastron respiration.

Adults are known to walk underwater against current rather than swimming. Both life stages are strongly associated with the benthic zone of fast-flowing streams.

Larvae and adults contribute to nutrient cycling in headwater stream ecosystems through grazing and detritivory. Serve as indicators of high water quality due to sensitivity to hypoxia and pollution.

Used as bioindicators for monitoring stream health and water quality. No direct economic importance.

• CylloepusSimilar genus of riffle beetles distinguished by having five visible abdominal ventrites rather than six.
• MacrelmisAnother elmid genus with overlapping distribution; separated by differences in tarsal formula and body proportions.

• riffle beetle
• Elmidae
• aquatic beetle
• Neotropical
• Colombia
• stream insect
• bioindicator

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life