Rheophilic
Guides
Antocha
Antocha is a genus of crane flies (Limoniidae) comprising approximately 161 species across three subgenera. The genus is globally distributed with highest diversity in the Oriental (83 species) and East Palearctic (53 species) regions. Larvae are aquatic and rheophilic, inhabiting fast-flowing streams and rivers where they construct silken tubes on submerged rocks. The genus exhibits notable sensitivity to hydrological disturbances, making it a potential indicator of stream ecosystem health.
Astacidae
Astacid Crayfishes, Freshwater Crayfish
Astacidae is a family of freshwater crayfish comprising four extant genera: Astacus, Austropotamobius, Pontastacus, and Pacifastacus. Members are native to Europe, western Asia, and western North America. The family is distinguished by a gonopore positioned on the coxa of the third pair of walking legs in males (fifth pair in females), a trait shared with all Astacoidea. Several species, particularly Pacifastacus leniusculus (signal crayfish), have become invasive outside their native ranges, carrying crayfish plague (Aphanomyces astaci) that threatens native European populations.
Cinygma lyriforme
Cinygma lyriforme is a species of flatheaded mayfly in the family Heptageniidae, originally described as Ecdyonurus lyriformis by James Halliday McDunnough in 1924. The species name "lyriforme" refers to the lyre-shaped pattern characteristic of this taxon. Like other members of Heptageniidae, it possesses dorsoventrally flattened nymphs adapted for clinging to substrates in flowing water. The genus Cinygma is a small Nearctic genus with limited species diversity.
Isoperlinae
Stripetail Stoneflies, Springflies
Isoperlinae is a subfamily of stoneflies in the family Perlodidae, distributed across the Palaearctic and Nearctic regions. Members are commonly known as stripetails or springflies. The subfamily includes approximately 12 genera, with Isoperla being the most speciose and well-known. These stoneflies are aquatic insects whose nymphs inhabit running waters.
Psephenus herricki
Herrick's Water Penny Beetle
Psephenus herricki is a water penny beetle found in eastern North America. Larvae are highly flattened and inhabit stream riffles, where they occupy interstitial crevices and undersides of stones. The species exhibits specific behavioral and morphological adaptations to flowing water environments, including thigmokinesis that inhibits movement when wedged in substrate. Adults are associated with wave-splashed rocks that serve as mating sites and oviposition substrates.
Somatochlora filosa
Fine-lined Emerald, cordulie tricoteuse (French)
Somatochlora filosa, known as the fine-lined emerald, is a species of emerald dragonfly in the family Corduliidae. It is found in North America, with its first Canadian record documented in Quebec in 2016. The species is classified as rheophilic, inhabiting river and stream environments. The IUCN lists it as Least Concern with a stable population.
Somatochlora linearis
Mocha Emerald
Somatochlora linearis, the Mocha Emerald, is a species of emerald dragonfly in the family Corduliidae. It is found in North America, with confirmed records from the United States and Québec, Canada. The species has been described as rhéophilic (adapted to flowing water habitats). The IUCN lists it as Least Concern with a stable population.