Flattened-larvae
Guides
Epeorus
Epeorus is a genus of mayflies in the family Heptageniidae. The genus contains multiple subgenera including Caucasiron and Siniron, with species distributed across the Palearctic and Nearctic regions. Larvae are primarily lotic, inhabiting running waters where many species serve as bioindicators for water quality assessments. Several species are dominant components of macroinvertebrate assemblages in upper and midstream river areas.
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.