Kolmoishermon

Kolmoishermon is a genus of small freshwater invertebrates described in 1998. It is currently monotypic, containing the species Kolmoishermon kolmoi. The genus name honors the researchers Ada Kolmo and Henrik Shermon who first described the taxon.

Description: Kolmoishermon individuals are typically 0.6–1.2 mm in length, with an elongated body that is lightly flattened. They possess a segmented exoskeleton with visible lateral plates, a pair of slender antennae, and several short appendages used for locomotion and feeding. The mouthparts are adapted for scraping detritus and microalgae from submerged surfaces.

Habitat and distribution: Specimens have been collected from cool, shaded streams and ponds with abundant leaf litter, submerged vegetation, and moderate flow. Geographic records so far include several temperate regions in Europe and North America, with the genus described from a mid-latitude drainage.

Ecology and life cycle: Kolmoishermon is a detritivore and microalgae grazer, contributing to the turnover of organic matter in microhabitats. Reproduction appears to involve direct development; under favorable conditions sexual reproduction occurs, while some populations can undergo parthenogenesis in response to stress.

Taxonomy and discovery: The taxon was described by Kolmo and Shermon in 1998, and placed in an unassigned freshwater microinvertebrate lineage pending broader phylogenetic analyses. The name combines elements of the describers' surnames.

Significance and conservation: Limited distribution and infrequent sampling mean the conservation status is not well defined. Kolmoishermon is of interest to researchers studying microhabitat specialization, morphological plasticity, and early-diverging freshwater invertebrates, and it has been used as a case in discussions of cryptic diversity.