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bioRxiv · 10.1101/2023.05.20.538492

Species composition of Culicidae (Diptera) in Bromeliads in rural and urban areas of Londrina, Brazil

Silva, B. P.·Arcos, A. N.·Ferreira, F. A. d. S.·Medri, C.·ZEQUI, J. A. C.
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Abstract

Bromeliaceae, has 82 genera and 3,719 species found throughout the Neotropical region, from the southern United States to central Argentina and Chile. These plants are present in environments with different characteristics and have high endemism in the Atlantic Forest in Brazil. Tank bromeliads stand out for their morphology, which forms permanent water-accumulating compartments called phytotelmata, rich in organic detritus and living organisms. Culicidae use phytotelma as a breeding ground, and some species of Wyeomyia are highly dependent on these tanks. Research on the importance of bromeliads as water reservoirs that may favor the reproduction of mosquitoes that carry pathogens are controversial. Some studies indicate that these plants are potential breeding grounds for Aedes, while others suggest that they are not preferential foci for synanthropic mosquitoes, as is the case for A. aegypti. This work aimed at verifying the presence of Aedes and other Culicidae in native bromeliads in natural habitat and under ornamental cultivation in an urban environment, comparing the incidence of larvae in these possible breeding sites and contrasting with the luminosity and accumulated water volumes. Differences in species composition were observed between rural and urban environments. In the rural environment, four species of Culicidae were collected, the most abundant being Wyeomyia galvaoi -19 specimens, followed by Culex (Microculex) imitator - five specimens, while Aedes aegypti and Toxorhynchites sp 1, were the least abundant, with two individuals each. In the urban environment, five species were found, with greater abundance of Aedes aegypti (461 individuals), followed by Aedes albopictus (45), Toxorhynchites sp. 01 (3), Wyeomyia sp1 (02), and Wyeomyia galvaoi (01) In addition, these phytotelma showed great diversity of other organisms, such as: mites, nematodes, protists, rotifers, ostracods, and insect larvae of the Chironomidae, Syrphidae and Tachinidae families. The study concluded that the incidence of mosquito larvae in native bromeliads is low, and that luminosity and accumulated water volumes can influence the presence of larvae. The authors emphasize that the importance of bromeliads in mosquito reproduction may vary according to several factors.

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Silva, B. P., Arcos, A. N., Ferreira, F. A. d. S., Medri, C., ZEQUI, J. A. C.. 2023-05-21. Species composition of Culicidae (Diptera) in Bromeliads in rural and urban areas of Londrina, Brazil. https://doi.org/10.1101/2023.05.20.538492

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