New cladoceran records from Lake Paranoá, Central Brazil

Abstract

The zooplanktonic community of Lake Paranoá has been studied for more than thirty years. Until 1998, when it was considered eutrophic, only three cladoceran species were known from the reservoir. Since 1999, when Lake Paranoá underwent intentional flushing, definite changes in species diversity and composition were identified. At the same time, exploratory studies on littoral cladoceran species were being done. The present study aims to provide additional information on the cladoceran species composition of Lake Paranoá. Seven new species records are presented, four of them also representing the first record from the Federal District (Brasília). The population previously considered as belonging to Bosmina longirostris was reconsidered and re-identified as Bosmina freyi. Figures and comments on species taxonomy and distribution are also provided.

Distribution and abundance of Cladocera (Branchiopoda) in the Paraíba do Sul River estuary, Rio de Janeiro, Brazil

“…The species of cladocerans (Table 1) found in the study area are typical of marine and estuarine environments (Coelho-Botelho et al, 1999;Lopes, 1996;Montú, 1980;Nogueira et al, 1999;Valentin & Marazzo, 2003;Marazzo & Valentin 2004), but most are from freshwater environments (Elmoor-Loureiro, 1997;Elmoor-Loureiro et al, 2004;Hann & Zrum, 1997;Montú, 1980;Neves et al, 2003;SantosWisniewski et al, 2002;Sampaio et al, 2002;Serafim Jr. et al, 2003).…”

“…Consequently this species does not seem to be able to survive in brackish waters in the Paraíba do Sul River estuary, despite being considered an euryhaline-limnetic species, occurring in other environments with salinities from 0-31.5 (Montú, 1980). This is another cladoceran species that may occur in several types of freshwater bodies (Elmoor-Loureiro et al, 2004;Montú, 1980), a good indicator of the trophic state of the environment (Sampaio et al, 2002). In Brazil, it has been recorded in the states of Alagoas, Pernambuco, Mato Grosso do Sul, Minas Gerais, Rio Grande do Sul and in the Distrito Federal (Elmoor-Loureiro, 1997).…”

“…The same occurred with Bosmina longirostris, which was recorded in brackish waters during spring. This species seems to be also abundant in wetlands during spring (Hann & Zrum, 1997); lakes (Elmoor-Loureiro et al, 2004) and rivers (Serafim Jr. et al, 2003). It is also a good indicator of the trophic state of lakes, particularly of eutrophic environments (Sampaio et al, 2002).…”

“…There are few studies on cladocerans in tropical estuarine regions. Very little is known on the life habits of the cladoceran species found in Brazil (Elmoor-Loureiro, 1997), the majority of studies focusing on limnic environments such as reservoirs and lakes (Sampaio et al, 2002;SantosWisniewski et al, 2002;Elmoor-Loureiro et al, 2004) and flooded river plains (Neves et al, 2003;Serafim Jr. et al, 2003). On marine environments, there are works by Marazzo & Valentin (2000; and Valentin & Marazzo (2003) at Guanabara Bay ;Resgalla Jr. & Montú (1993) on the coast of Rio Grande do Sul State.…”

Pelagic and littoral cladocerans (Crustacea, Anomopoda and Ctenopoda) from reservoirs of the Northwest of São Paulo State, Brazil

“…We considered littoral zones with more than two species of macrophyte as high diversity macrophyte zones and up to two species as low diversity macrophyte zone. Species identification was carried out under optical microscope, using specific identification keys (Smirnov 1996, Elmoor-Loureiro 1997 and papers with species details (Elmoor-Loureiro et al 2004). Cladocerans were counted in 1 ml-subsamples taken with the pipette, placed in the counting chamber and counted using a stereoscopic microscope.…”