Tree hole mosquito species composition and relative abundances differ between urban and adjacent forest habitats in northwestern Argentina

Abstract

Water-holding tree holes are main larval habitats for many pathogen vectors, especially mosquitoes (Diptera: Culicidae). Along 3 years, the diversity and composition of mosquito species in tree holes of two neighbouring but completely different environments, a city and its adjacent forest, were compared using generalized linear mixed models, PERMANOVA, SIMPER and species association indexes. The city area (Northwest Argentina) is highly relevant epidemiologically due to the presence of Aedes aegypti L. (main dengue vector) and occurrence of dengue outbreaks; the Yungas rainforests are highly biologically diverse. In total seven mosquito species were recorded, in descending order of abundance: Ae. aegypti, Haemagogus spegazzinii Brèthes, Sabethes purpureus (Theobald), Toxorhynchites guadeloupensis Dyar and Knab, Aedes terrens Walker, Haemagogus leucocelaenus Dyar & Shannon and Sabethes petrocchiae (Shannon and Del Ponte). The seven mosquito species were recorded in both city sites and forested areas; however, their mosquito communities significantly diverged because of marked differences in the frequency and relative abundance of some species: Tx. guadeloupensis and Ae. aegypti were significantly more abundant in forest and urban areas, respectively. Positive significant associations were detected between Ae. aegypti, Hg. spegazzinii and Hg. leucocelaenus. The combined presence of Ae. aegypti, Haemagogus and Sabethes in the area also highlight a potential risk of yellow fever epidemics. Overall results show an impoverished tree hole mosquito fauna in urban environments, reflecting negative effects of urbanization on mosquito diversity.

Colonized Sabethes cyaneus, a Sylvatic New World Mosquito Species, Shows a Low Vector Competence for Zika Virus Relative to Aedes aegypti

“…While Sabethes cyaneus has not itself been implicated as a vector of any arbovirus, other Sabethes species have been shown to carry the flaviviruses YFV [ 31 , 32 , 33 , 34 , 35 ], dengue virus [ 36 ], and Ilheus virus [ 37 ] as well as the rhabdovirus Xiburema virus [ 38 ]. Sabethes species are highly abundant in the forest canopy [ 39 , 40 , 41 , 42 ], occur in forested areas of large cities [ 43 , 44 , 45 ], have long lifespans in nature that exceed the 21 day EIP measured here [ 46 ], and have been collected via human land catch [ 47 , 48 ]. Together, these traits suggest that species in this genus have high potential act as bridge vectors [ 49 ] for spillback from humans to wildlife.…”

Redescription of immatures of Dasyhelea flavifrons Guérin-Méneville (Culicomorpha: Ceratopogonidae) and new contribution to the knowledge of its larval habitats

“…Tree holes were located in the city and in yunga forest patches to the north and east of An Acad Bras Cienc (2019) 91(1) e20180047 3 | 14 town, while snail shells were collected from forest patches only. For details on tree holes selection see Mangudo et al (2015Mangudo et al ( , 2018 and for snail shell sampling see Mangudo et al (2017). larvae were preserved in ethanol 80% and pupae were kept alive in the laboratory isolated in plastic vials (2 mm) holding water from the larval habitat and containing a piece of humid filter paper, to maintain the humidity inside the vials, until adult emergence.…”

Field comparison of oviposition substrates used in ovitraps for Aedes aegypti surveillance in Salta, Argentina

“…Thus, there were data for 68 ovitraps from Salta (from 17 sites) and 96 ovitraps from Hipólito Yrigoyen (from 24 sites). Previous and ongoing studies on tree hole and container mosquitos in Salta province (e.g., Espinosa et al, 2016;Mangudo, Aparicio, & Gleiser, 2011;Mangudo, Aparicio, Rossi, & Gleiser, 2018; José F. Gil pers. obs.)…”