Diversity of chironomid larvae in palustrine wetlands of the coastal plain in the south of Brazil

Abstract

The Chironomidae of tropical South America are a very rich species, but are scarcely known. The range of environmental conditions under which chironomids are found is more extensive than that of any other group of aquatic insects. The objectives of this study were to carry out a diversity survey of chironomid larvae in wetland systems of the coastal plain in the south of Brazil and to analyze the effects of area, altitude, water conductivity, nitrate and phosphorus concentrations, and the life form of the dominant plant species on chironomid richness and composition. Collections were carried out from March to April in 2002. A total of 30 taxa (23 morphospecies and 7 species) distributed along 23 genera were found, and the Chironominae showed the greatest richness, followed by Tanypodinae and Orthocladiinae. The chironomid richness was higher in the emergent than in the multistratified wetland class. The wetland area, altitude, nitrate and phosphorus concentrations, and water conductivity did not influence the richness of Chironomidae. The Chironomidae genera and species were present in both the wetland classes (emergent and aquatic bed vegetation). However, while Chironominae were more frequent in the emergent than in the aquatic bed wetlands, no difference was observed for Tanypodinae. The aquatic vegetation was an important environmental predictor for chironomid larvae richness in the studied wetlands in the south of Brazil.

Diversity of Non-Biting Midge Larvae Assemblages in the Jacuí River Basin, Brazil

“…Additionally, inventories and ecological studies about the assemblages of Chironomidae have concentrated on the northern and southeastern regions of the country (ie.g., Callisto and Esteves 1998; Sanseverino et al 1998; Serrano et al 1998; Henriques-Oliveira et al 1999; Siqueira and Trivinho-Strixino 2005; Sanseverino and Nessimian 2007; Roque et al 2010). In the southern region, which has a climate tending toward temperate (Maluf 2000), studies are incipient, and focus primarily on lentic environments such as lakes and wetlands (e.g., Wiedenbrug et al 1997; Stenert et al 2004; Panatta et al 2006, 2007). The few studies on the spatial distribution of the assemblages of larvae of Neotropical Chironomidae have focused mainly on local or small regional scales (e.g., Corbi and Trivinho-Strixino 2008a; Sonoda et al 2009).…”

Factors structuring the spatial distribution of Chironomidae larvae community in the floodplain of the northern Pantanal, Brazil

“…This genus can feed on detritus or animals (Chironomidae larvae and microcrustacean) and has low selectivity, considered generalist (Henriques-Oliveira et al, 2003;Panatta et al, 2006).…”

“…Flood duration is the determinant ecological factor for the distribution of plant species (Rebellato and Cunha 2005;Fantin-Cruz et al, 2010). However, the vegetation in great part of the Pantanal has been altered for the livestock production (Junk and Cunha, 2012).…”

Responses of freshwater molluscs to environmental factors in Southern Brazil wetlands

“…The macroinvertebrate structure in wetlands has been associated with area and habitat heterogeneity (Oertli et al, 2002;Batzer et al, 2004;Panatta et al, 2006;Studinski and Grubbs, 2007;Stenert et al, 2008); hydroperiod (Tarr et al, 2005;Whiles and Goldowitz, 2005;Stenert and Maltchik, 2007); altitude (Oertli et al, 2002;Jacobsen, 2004); water chemistry (Heino, 2000;Batzer et al, 2004), and water depth and temperature (Zimmer et al, 2000;Hall et al, 2004;Tarr et al, 2005;Studinski and Grubbs, 2007). However, most of these surveys were developed in the North Hemisphere and Australia.…”