Biofilm-feeder
Guides
Heterelmis
riffle beetles
Heterelmis is a genus of aquatic beetles in the family Elmidae, commonly known as riffle beetles. The genus includes several described species, with Heterelmis comalensis being particularly notable as an endangered species endemic to spring systems in Texas. Members of this genus are fully aquatic, inhabiting oxygen-rich flowing water environments where they feed on microbial biofilms. Some species have reduced or non-functional wings, limiting their dispersal ability and making them vulnerable to habitat degradation.
Pallopteridae
flutter-wing flies, trembling-wing flies, waving-wing flies
Pallopteridae is a small family of acalyptrate flies comprising approximately 70 species across 15 genera, distributed primarily in temperate regions of both Northern and Southern Hemispheres. Adults are recognized by their characteristic wing vibration behavior, which produces the common names flutter-wing, trembling-wing, or waving-wing flies. The family exhibits diverse larval feeding strategies including saprophagy, phytophagy, and occasional zoophagy, with larvae developing in flowerheads, stems, and other plant tissues.