RESUMO
Several studies that involve a faunal survey of Cladocera in Brazil have been carried out in recent years; however, knowledge of the distribution and diversity of species of this group in semiterrestrial and aquatic bodies of rupestrian cerrado is still rare. The present study evaluated the richness and composition of cladoceran species in these environments in the central parts of the country. Samples were collected at nine sites of rupestrian cerrado from 2011 to 2012. In total, 47 cladocerans species were identified, belonging to six families, emphasizing the Chydoridae family with the greatest richness (32 species) and abundance. The species Bryospilus repens had its first record for the state of Goiás and the Brazilian Midwest. Other species were also recorded for the first time: Leberis davidi for the state of Minas Gerais, and Alona yara and Flavalona asymmetrica for the state of Bahia. This demonstrates that rupestrian cerrados are relevant for cladoceran diversity on a regional scale. Carrying out new inventories of cladocerans in similar phytophysiognomies could contribute significantly to the knowledge of the biodiversity of these animals in Brazil, in addition to providing updates on the geographic distribution of species already recorded in previous studies.
Assuntos
Cladocera , Besouros , Animais , Brasil , BiodiversidadeRESUMO
The aim of this study is to describe the limb morphology of Alonella dadayi Birge (Cladocera: Chydorida) and this species' morphometric variability regarding the carapace and postabdomen. We report for the first time a population whose individuals do not have denticles on the posteroventral corner of the carapace. Although we have observed intra- and interpopulation variability of the limbs (especially the proportion of Inner Distal Lobe setae), Alonella dadayi can also be differentiated from closely related species by the morphology of the exopodite of the second limb. The morphometric analyses show high variability in the shape of the carapace, when regarding the ventral margin and posterodorsal corner. In the postabdomen, we observed a significant variation in the preanal, anal and postanal margins. Keeping in mind the wide range of the geographic distribution of Alonella dadayi and its high morphological variability, it is possible that this taxon comprises a species complex. Such a chance needs to be tested in future studies.
Assuntos
Cladocera , Distribuição Animal , Estruturas Animais , Animais , Tamanho CorporalRESUMO
The main goal of this paper is to describe three new species of the genus Monospilus Sars, 1862 (Crustacea: Cladocera). Monospilus macroerosus sp. nov. differs from other species of the genus in several peculiar morphological traits, the most striking being the presence of a saw-shaped pecten of teeth on the postabdominal claw. This species inhabits semiterrestrial habitats (wet leaf litter on hydromorphic soil from gallery forest), exhibiting adaptations related to movement and food handling in this type of habitat. Monospilus brachyspinus sp. nov. inhabits truly aquatic habitats, where lives being associated with macrophytes and submerged leaves. It may be recognized by the postabdominal claw, which is armed with proximal spinulae modified in a short spine. In Monospilus sp., the proximal spinulae are modified in a long and slender spine. So far, Monospilus sp. occurs in southern South America, while Monospilus macroerosus sp. nov. and Monospilus brachyspinus sp. nov. occur in the Cerrado biome in Brazil, in the central portion of South America. Some conclusions about the conservation status of new species also are made.