Influence of Pools and Riffles on Chironomidae Diversity in Headwater Streams of the Atlantic Forest

Abstract

Studies on mesohabitat scale have been used to shed light on the ecology and distribution of chironomid larvae in small streams. Thus, the objective of the present study was to examine the diversity and distribution of the Chironomidae assemblage on the mesohabitat scale in three streams located in different preserved areas of southeastern Brazil. In each stream, litter samples were obtained in the dry season of 2010 in ten pools and ten riffles with a Surber sampler (area 0.04 m(2); mesh size 0.21 mm). The abundance was similar among streams and between mesohabitats, while the estimated richness was highest in riffles. There was a difference in the composition of the Chironomidae assemblages between the mesohabitats, although the litter composition was similar between them, indicating the importance of current speed on the distribution of the taxa. The dispersion of the sample units (β-diversity) of riffles and pools was similar, although it was different among the three streams. The results of this study provide further evidence of the importance of habitat heterogeneity within streams as a generator of diversity for Chironomidae in tropical lotic systems.

Madicolous Chironomidae from the Brazilian Atlantic Forest: a checklist with notes on altitudinal distributions (Diptera, Insecta)

“…Madicolous habitats have never been formally studied in Brazilian mountainous regions, in contrast to other Atlantic Forest water bodies in which the Chironomidae fauna have already been extensively investigated (Henriques-Oliveira et al 2003, Roque et al 2007, Silveira et al 2015). Taxonomists, and especially ecologists, have paid little attention to semi-aquatic and terrestrial Chironomidae, and therefore, madicolous species were completely overlooked.…”

Aquatic insect communities in headwater streams of Ciliwung River watershed, West Java, Indonesia

“…Most species of Chironomus have generalist and opportunistic feeding habits, using plant material and associated micro-organisms as a food source (Naser and Roy 2012). Therefore, their distribution and abundance are strongly influenced by leaf litter features (Silveira et al 2015). Chironomidae commonly posses the dominant status at the expense of other more sensitive groups, such as mayflies, stoneflies, and caddisflies (Li et al 2010).…”

“…Vegetation along the forest stream banks reduce the autotrophic production because of shading and provides a large litter amount composed of leaves, stems, fruits, and seeds. Furthermore, the accumulation of allochthonous material in stream beds increases the spatial heterogeneity of the environment, enabling the coexistence of a rich variety of aquatic insects (Silveira et al 2015). In forest headwater streams, the majority of energy inputs are detrital, therefore maintaining diverse riparian inputs of organic matter is important for detritivore productivity in forested headwater watersheds (Eckert et al 2020;Eggert et al 2020).…”