An annotated checklist of recent non-marine Ostracoda (Crustacea) from Argentina, South America.

According to an updated list of extant non-marine ostracods, there are 2,330 subjective species in 270 genera in the world, of which 333 species are known from the Neotropical region. However, the knowledge about the ostracod fauna in Argentina is scarce, fragmented and incomplete. Thus, the aim of this study was to present the first checklist of the recent non-marine ostracods from Argentina, including geographical distributions and ecological characteristics of the species. Thus far, 66 ostracod species in 33 genera and 7 families have been recorded in non-marine Argentinian environments. Of the total number of species, 29% can be considered endemic to the country. Most of the species were recorded in alkaline, freshwater to oligohaline cold waters and mainly in low to moderate altitude environments. Our results showed that most studies were mainly carried out in the Pampean and Patagonia region and, therefore, the diversity record of ostracods in Argentina is biased towards these regions.

Disentangling vegetation structure effect on invertebrate communities in contrasting growth periods in subtropical protected wetlands of Argentina.

This study assesses the effect of vegetation structure on the subtropical invertebrate communities in contrasting sampling dates of macrophyte populations in the RAMSAR site of Iberá wetlands, South America. Invertebrates associated with the submersed Egeria najas and the floating rooted Pontederia azurea were chosen to provide a model involving different microhabitat complexity. The results suggest that vegetation structure provided by the two macrophyte species supported significant differences in the density of animals, with invertebrate abundance of E. najas twice as high as on P. azurea. Abundance showed no significant differences in both contrasting sampling dates, growth and decline. Our result clearly showed invertebrates exclusively associated with each macrophyte species, as well different invertebrate taxa dominating in each sampling date (decline: Cladocera; growth: Aphididae, Belostomatidae and Planorbidae). We also show that working at the taxonomic levels of family could be a sensible trade-off between taxonomic identification effort versus reaching reliable and useful results for environmental monitoring and natural resource management in highly diverse subtropical wetlands. Our results emphasize the role of vegetation structure on invertebrate communities, as well suggest that the growth cycle of macrophyte populations could be a relevant variable influencing these animals in pristine subtropical wetlands.