Abstract

The life cycles and the nymphal feeding habits of the Plecoptera species Antarctoperla michaelseni (Klapálek, 1904) (family Gripopterygidae) and Klapopteryx armillata Navás, 1928 (family Austroperlidae) are studied in the Chanleufu Stream, southern Chile. Both species have a slow seasonal univoltine life cycle. Antarctoperla michaelseni has a long flight period from May to November, while K. armillata has a short flight period from July to August. The main components of the nymphal diet of both species are diatoms and plant detritus but they are found at a different proportion in each species, so A. michaelseni can be classified mainly as scraper and K. armillata as shredder from a functional feeding group point of view. By analysing stomach contents throughout the year, we observe ontogenetic changes. Smaller nymphs tend to have scraping and collector-gatherer behaviour, while as they grow older, they tend to switch to a more shredder behaviour. Our results are compared with previous information for these same species and with data on the related species. © 2025 Informa UK Limited, trading as Taylor & Francis Group.