Life history, feeding and secondary production of two Nemouroidea species (Plecoptera, Insecta) in a temporary stream of the Southern Iberian Peninsula

We studied some ecological aspects of two taxa of Nemouroidean stonefl ies (Tyrrhenoleuctra sp. and Brachyptera vera cordubensis) from a seasonal stream in Southern Europe. Tyrrhenoleuctra sp. shows a univoltine life cycle with a nymphal dormancy during the drought, and a long fl ight period. The eggs of this species are fully developed when laid, and hatch rapidly after laying, indicating a certain degree of ovoviviparism. The fi rst instar nymph is described for the fi rst time. In contrast, B. vera cordubensis shows a fast seasonal univoltine life cycle with an egg dormancy. The feeding behaviour study reveals that Tyrrhenoleuctra sp. can be catalogued mainly as a gatherer-collector while B. vera cordubensis can be classifi ed mainly as a scraper, although neither of them belong solely to a single functional group. No signifi cant changes are detected in the diet in relation to nymphal size, although larger individuals of B. vera cordubensis ingest more CPOM than small ones. Both taxa had similar biomass, but B. vera cordubensis had a higher secondary production and annual P/B rate.