Latitudinal gradient variations in caddisfly assemblages across mountain forest streams

REYNAGA, MARÍA CELINA; PERO, EDGARDO JAVIER IGNACIO; RUEDA MARTÍN, PAOLA

Quito

Congreso; Congreso Aquatrop 2018; 2018

Universidad San Francisco de Quito - Universidad de las Américas

Evidence oflatitudinal diversity gradient of benthic macroinvertebrates is variable. Thisstudy analyzed how varies the species and genus richness, composition and structureof caddisfly (Insecta: Trichoptera) assemblages in Yungas mountain forest ofArgentina through a latitudinal gradient from 22º (Tropical) to 28º(Subtropical). Qualitative and quantitative data from 21 sites including differentstreams were compared across six latitudinal ranges. The assemblage structurewas analyzed by comparing Rank-abundance (RA) curves. Nonmetric-Multidimensional Scaling (NMDS) and k-medoid clustering PAM method weremade using Dissimilarity among assemblages. Stream environmental variables werecompared for discard important differences among sites. The species richness increasedmeaningfully through the latitudinal gradient from high to low latitude. Althoughgenus richness evidences the same pattern, it was less noticeable. RA curvesshows changes in assemblage?s composition and structure across the latitudinal gradient.The NMDS and PAM analyses revealed that the overall structure of the Trichopteraassemblages agrees adequately with the latitudinal gradient. The sampling siteswere segregated in two groups: the northern sites (22º-25º) and the australsites (25º-28º). This distribution and richness patterns are similar to othersobserved in plants and vertebrates from Yungas forest.