RESUMO
The aim of the present study was to investigate the variables associated with the composition of mosquito species in rain pools of 'Bosque de Ezeiza', a large peri-urban forested park of Buenos Aires city, Argentina. A total of 12 rain pools were sampled biweekly over a 1-yr period in search of mosquito immature stages. Mosquito immature stages were present in all the occasions in which water bodies were recorded. A total of 14 species of five genera were identified, with the highest abundances observed in autumn and spring. The total abundance varied among dates according to previous temperature, precipitation, and flooding conditions. Only one species, Psorophora cyanescens (Coquillett) (Diptera: Culicidae), was associated with extreme conditions (high temperature and prolonged period of drought). Besides drought periods, two main variables were related to species composition: temperature, which accounted for seasonal changes in species composition, and flooding history, which accounted for the predominance of floodwater mosquito species on recently flooded dates and for that of stagnant water species on dates with a longer permanence of water. Regarding the pools, the most important variables accounting for species composition were the insolation level and the variability in the flooded area, with floodwater mosquitoes associated with pools with high variability in the flooded area. Interestingly, Culex (Mel.) pilosus (Dyar and Knab) (Diptera: Culicidae) showed temporal and spatial dynamics more similar to floodwater species than to stagnant water species in the rain pools studied.
Assuntos
Culicidae/fisiologia , Meio Ambiente , Animais , Argentina , Cidades , Culicidae/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Parques Recreativos , Densidade Demográfica , Estações do AnoRESUMO
A new spinicaudatan species, Eulimnadia pampa sp. nov., is described from Argentina mostly based on the differential egg morphology. This species was collected from rainwater pools from Buenos Aires City and the provinces of Buenos Aires and Entre Ríos, and compared to other Neotropical species. Previous Argentine record of E. brasiliensis is shown to belong to our new species, which represents the southernmost Neotropical Eulimnadia. We also present new records of the Paraguayan Eulimnadia ovisimilis Martin and Belk, 1989 from northeastern Argentina. Eulimnadia santiaguensis is treated as a species inquirenda, thus we recognize only three Eulimnadia species in Argentina: E. pampa sp. nov., E. ovilunata and E. ovisimilis, and we provide a brief indentification key. We present the first description and SEM images of the putative Eulimnadia spermatophore, which we found in the new species.
Assuntos
Crustáceos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Argentina , Tamanho Corporal , Crustáceos/anatomia & histologia , Crustáceos/crescimento & desenvolvimento , Ecossistema , Feminino , Masculino , Tamanho do ÓrgãoRESUMO
Larvae of Culex (Melanoconion) pilosus were collected during February-April 2014 in temporary pools in "Bosques de Ezeiza," a large forested park, near Buenos Aires city, Argentina. This is the first record in Buenos Aires Province, extending the distribution of this species 380 km to the south. Regarding habitat use, Cx. (Mel.) pilosus is a generalist, although a slight association of larval abundances with pools of lower pH and higher vegetation cover was observed. The comparison of larval instars of Cx. (Mel.) pilosus with those of other genera suggests a life-history strategy similar to that of floodwater mosquitoes.