The reproductive biology (drumming call, mating behaviour, fecundity and egg structure) of Isoperla curtata, an endemic species from the Southern Iberian Peninsula, is described. The male's mating call has a diphasic pattern, with a mean of 17.3 beats per call (range = 8-27; SD = 4.7) and a duration of 792.9 ms per call (range = 228-1312; SD = 307.9). This call differs from that of other species of Isoperla in having two distinct phases with different millisecond intervals, and is species-specific. Mating lasts between 131 and 3864 seconds (mean = 2180.9 s and SD = 1027.8). Since males and females mate more than once (mean number of matings per female was 1.85 and per male 2.25), the species is polyandric and polygynic. The position adopted by the male during mating is different from that described for other stonefly species. Other mating behaviours are interpreted as displacement manoeuvers, tactile stimulation and possibly sexual selection by cryptic female choice. There was a statistically significant correlation between size and the number of matings in females (r = 0.849; p = 0.016), but not in males. Each female laid between one to four egg masses composed of an average of 88.7 eggs. Maximum fecundity was 319 eggs. The mean egg volume was 80.5 x 105 pm3 which is very similar to that of other Isoperla species. An outstanding morphological characteristic of the egg is the lobed outline of the chorion cells.

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Allochthonous leaf litter from riparian vegetation represents the main energy source in small lotic systems, where canopy limits autochthonous primary production. In this study, leaf packs of two tree species (the native Salix neotrichia and the introduced Populus x canadensis) were positioned in the Fardes Stream (southern Spain) to analyze the macroinvertebrate colonization. On two dates, leaf packs were removed, and colonizing macroinvertebrates were collected and identified; at the same time, Surber samples were collected to characterize the riverbed macroinvertebrate coenosis. Leaf packs attracted rich and varied communities of benthic macroinvertebrates, with an increase of the abundance of most taxa over time. No significant differences were found between the colonizing communities of the two leaf types. Some macroinvertebrate species showed a preference for leaf packs, probably due to trophic or hydrologic factors. Considering functional feeding groups, increases in shredders and scrapers and decreases in predators and filterers were detected over time, while collector-gatherers almost did not change in abundance.

The male call of Capnioneura mitis, produced by drumming, is recorded and analyzed for the first time. It also represents the first known signal for the genus. It consists of a highly variable number of beats (2-32) with inter-beat duration approximately constant along the call, but inter-beat duration is temperature dependent. Thus, at 13°C the mean inter-beat duration is 1.397 s (SD = 0.050) while at 21°C it is 1.139 s (SD = 0.093). The call pattern exhibited by this species, as those of the majority of previously studied Capniidae species, can be catalogued as an ancestral or near-ancestral percussive monophasic signal.

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