Nymphal biology of Capnioneura gelesae Berthélemy & Baena, 1984 (Plecoptera, Capniidae) in temporary streams of the Sierra Morena (southern Spain)We present the results of a study of the life cycle and nymphal feeding of the stonefly Capnioneura gelesae Berthélemy & Baena, 1984 in two temporary streams of the Sierra Morena (southern Iberian Peninsula). The species has a fast-seasonal univoltine life cycle at both sites, but the diet differs depending on the stream. Nymphs from one stream feed mainly on detritus, so they can be classified as gatherer-collectors from a trophic, functional point of view, and those from the other stream feed mainly on diatoms, behaving as scrapers. However, the study of the diet across the nymphal growth period shows a slight trend towards shredder behaviour in the largest nymphs from one population. When comparing these results with those from other Capnioneura species, we observe the existence of interspecific variability. The most similar species in terms of life cycle and feeding is C. petitpierreae Aubert, 1961, which is also an inhabitant of Mediterranean temporary streams.