the.com/stonefly
a bug so allergic to pollution its mere presence certifies your water as drinkable.
pollution snitchScientists use their presence to grade water quality.
push-up displayMales do push-ups to drum mating signals.
ancient lineageAmong the oldest winged insects, predating dinosaurs.
barely flyMany species are weak, reluctant fliers.
nymph yearsLarvae lurk underwater for up to three years.