Spatial distribution, feeding and length-mass relationships of Diamphipnopsis samali (Plecoptera, Diamphipnoidae) in a North Patagonia Andean stream, Argentina

OMAD GUILLERMO HUGO; PESSACQ PABLO; EPELE LUIS BELTRAN

REVISTA DE LA SOCIEDAD ENTOMOLóGICA ARGENTINA

SOCIEDAD ENTOMOLÓGICA ARGENTINA

Lugar: Mendoza; Año: 2015 vol. 74 p. 27 - 35

0373-5680

Some aspects of the biology and ecology (distribution pattern, feeding habits and length-mass relationship) of a population of Diamphipnopsis samali are studied in a first order stream surrounded by exotic forest located in North Patagonia, Chubut province, Argentina. Two samplings were performed during high and low water periods. All information was treated with fixed-effects 2-factor ANOVA models to assess significant differences. Mouth parts analysis of D. samali indicates that it corresponds to an intermediate type between carnivorous and herbivorous-detritivorous type. The guts content shows that the species specially fed on wood and fungal hyphae. No significant difference on the consumed food between sampling periods was found, even though there were significant differences between food content on large and small larvae. Regarding the habitat there was a clear preference for habitats waterfall and log and the difference between run and pool was also significant. There were no significant differences in substrate preference between high and low water periods. This Patagonian endemic species seems to be well adapted to the presence of exotic riparian forest using fallen logs for shelter and food.