RESUMO
During various studies of freshwater quality, twenty-four species of Smicridea were collected in Bolivia. This brings to thirty-one the number of Smicridea species present in this country. Four belong to the subgenus Smicridea Mclachlan J Linnean Soc London Zool 11: 98-141, 1871, which is recorded for the first time for the country. Additionally, 16 species in the subgenus Rhyacophylax Müller Zool Anzeiger 2: 38-40, 1879, are also registered for the first time. Three species are new and described from males: Smicridea (Rhyacophylax) molinai sp. nov., Smicridea (Rhyacophylax) ruedamartinae sp. nov., and Smicridea (Smicridea) moyai sp. nov.
Assuntos
Insetos/classificação , Animais , Bolívia , Insetos/anatomia & histologia , Masculino , RiosRESUMO
Aquatic ecosystems of the Bolivian Altiplano (â¼3800 m a.s.l.) are characterized by extreme hydro-climatic constrains (e.g., high UV-radiations and low oxygen) and are under the pressure of increasing anthropogenic activities, unregulated mining, agricultural and urban development. We report here a complete inventory of mercury (Hg) levels and speciation in the water column, atmosphere, sediment and key sentinel organisms (i.e., plankton, fish and birds) of two endorheic Lakes of the same watershed differing with respect to their size, eutrophication and contamination levels. Total Hg (THg) and monomethylmercury (MMHg) concentrations in filtered water and sediment of Lake Titicaca are in the lowest range of reported levels in other large lakes worldwide. Downstream, Hg levels are 3-10 times higher in the shallow eutrophic Lake Uru-Uru than in Lake Titicaca due to high Hg inputs from the surrounding mining region. High percentages of MMHg were found in the filtered and unfiltered water rising up from <1 to â¼50% THg from the oligo/hetero-trophic Lake Titicaca to the eutrophic Lake Uru-Uru. Such high %MMHg is explained by a high in situ MMHg production in relation to the sulfate rich substrate, the low oxygen levels of the water column, and the stabilization of MMHg due to abundant ligands present in these alkaline waters. Differences in MMHg concentrations in water and sediments compartments between Lake Titicaca and Uru-Uru were found to mirror the offset in MMHg levels that also exist in their respective food webs. This suggests that in situ MMHg baseline production is likely the main factor controlling MMHg levels in fish species consumed by the local population. Finally, the increase of anthropogenic pressure in Lake Titicaca may probably enhance eutrophication processes which favor MMHg production and thus accumulation in water and biota.
Assuntos
Monitoramento Ambiental , Lagos/química , Mercúrio/análise , Poluentes Químicos da Água/análise , Animais , Bolívia , Ecossistema , Eutrofização , Peixes , Cadeia Alimentar , Mineração , PlânctonRESUMO
The genus Claudioperla (Plecoptera: Gripopterygidae), which has been reported from Chile and Argentina to Colombia, was until now monospecific. The study of adults from various localities of the Bolivian Altiplano has resulted in the discovery of four distinct species. Three are new and described: Claudioperla rosalesi n. sp., Claudioperla moyai n. sp., and Claudioperla ruhieri n. sp. The fourth, Claudioperla tigrina (Klapálek), presents morphological variations with previous descriptions that are exposed and discussed. One of the new species, C. ruhieri, is apterous. The male of C. moyai is micropterous. Among South American stoneflies, they are the first cases of aptery and microptery reported outside of Patagonia. Adapted to extreme conditions of temperature and altitude, C. moyai and C. ruhieri are particularly threatened by the recent evolution of Bolivian glaciers.