The adults emerging from the water to mate. Larger species are often carnivorous. Many species are shredders. Generally indicators of cool, well oxygenated water. Note two caudal filaments and occipital ridge along back of head.
Adults do feed.
Males drum on various substrata to call mates. Nymphs go through 10-25 molts, depending the species. Most are univoltine, although species of Pteronarcyidae may require 2-3 years, with several size classes evident at a site. Look for thoracic gills in most taxa, and two cerci. Predatory taxa have large paraglossae compared to the glossae, while shredders have approximately equal sized paraglossae and glossae.