bioRxiv preprint doi: https://doi.org/10.1101/2020.06.23.166694; this version posted June 23, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. 1 Diversity of mosquitoes (Diptera: Culicidae) collected in different types of larvitraps in 2 an Amazon rural settlement 3 Running title: Anthropic environments and mosquito larvitraps 4 5 6 Jessica Feijó Almeida1,2,3¶*, Heliana Christy Matos Belchior1,4,5¶, Claudia María Ríos- 7 Velásquez1,2,4¶, Felipe Arley Costa Pessoa1,2,3,4¶* 8 9 1 Laboratório de Ecologia e Doenças Transmissíveis na Amazônia, Instituto Leônidas e 10 Maria Deane - Fiocruz Amazônia, Manaus, Amazonas, Brasil. 2 Programa de Pós- 11 Graduação em Condições de Vida e Situações de Saúde na Amazônia, Instituto Leônidas 12 e Maria Deane - Fiocruz Amazônia, Manaus, Amazonas, Brasil. 3 Programa de Pós- 13 Graduação em Entomologia, Instituto Nacional de Pesquisas da Amazônia, Manaus, 14 Amazonas, Brasil. 4 Programa de Pós-Graduação em Biologia da Interação Patógeno- 15 Hospedeiro, Instituto Leônidas e Maria Deane - Fiocruz Amazônia, Manaus, Amazonas, 16 Brasil. 5 Programa de Iniciação Científica do Instituto Leônidas e Maria Deane - Fiocruz 17 Amazônia, Manaus, Amazonas, Brasil. 18 *Corresponding author 19 E-mail: [email protected](JFA) 20 E-mail: [email protected](FACP) 21 22 ¶ These authors contributed equally to this work. 1 bioRxiv preprint doi: https://doi.org/10.1101/2020.06.23.166694; this version posted June 23, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. 23 Abstract 24 Anthropogenic environments provide favorable conditions for some species, which are 25 especially suitable for mosquitoes that present eclecticism at the moment of choice for 26 the site of oviposition. The present study, the diversity of mosquitoes in plastic container, 27 bamboo internode, and tire placed in forest, the forest edge, and peridomicile 28 environments in a rural settlement area was assessed. Eighteen sampling points were 29 chosen, delimited by a buffer 200 m, placed in environments: forest, forest edge, and 30 peridomicile. In each environment, larvitraps were installed, separated by a minimum 31 distance of 7 m and 1 m from the ground. A total of 10,131 immature mosquitoes of 20 32 species were collected. The most abundant species was Culex urichii (29.5%), followed 33 by Trichoprosopom digitatum (27.1%), and Cx. (Melanoconion) sp. (10,4%). There was 34 a difference in the composition of immature mosquito populations between larvitraps 35 (p<0.0005), and the plastic container hosted a greater diversity of species, whereas tires 36 presented a greater abundance of individuals. The forest, forest edge, and peridomicile 37 environments were also significantly different with regard to diversity of immature 38 mosquito populations (p<0.0010). The forest edge was the environment with the greatest 39 diversity of species, followed by the peridomicile and forest environments. In the forest 40 and peridomicile, plastic container larvitraps had the greatest diversity, whereas the forest 41 edge tire presented the largest number of individuals. Further, tire larvitraps collected the 42 largest number of individuals in all environments. We identified 10 species associated 43 with the bamboo internode and tire. We also observed the preference of species for 44 artificial larvitraps, such as the plastic container and tire, even in wild environments. 45 These artificial objects may represent a risk factor for the population living in this region, 46 as all vector species found in the study were present in plastic containers and tires. 47 2 bioRxiv preprint doi: https://doi.org/10.1101/2020.06.23.166694; this version posted June 23, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. 48 Introduction 49 Insects are the most diverse of all animal classes on the planet, and Brazil is the 50 country with the greatest insect diversity, with estimates of around 400-500 thousand 51 known species and most of these inhabiting the Amazon forest [1–3]. Anthropic activity 52 has affected some insect species, especially dipterian vectors such as sand flies, biting 53 midges, and mosquito populations [4–6]. Mosquitoes are vulnerable to changes in 54 environment and climate caused by deforestation and land use. Environmental changes 55 affect the distribution of Culicidae, leading to the increased abundance of some species 56 and a decreased abundance of others. Inevitably, the dynamics of disease transmission by 57 mosquitoes are also affected [7,8]. 58 Rural settlements are established in places that are favorable for human-vector 59 interaction due to their proximity to extensive forest areas and the lack of adequate 60 infrastructure for the residents who live there. In the Amazon region, precarious 61 assistance by the government in rural settlements and the habits of local residents have 62 led to an increase in cases of malaria and arboviruses [9,10]. 63 A study carried out in a settlement in Amazonas, Brazil found a high 64 seroprevalence of the Mayaro virus in residents, including people who did not enter the 65 forest, such as children and women, suggesting that this arbovirus is also transmitted by 66 species other than the main vector, Haemagogus janthinomys Dyar [11]. It was also 67 observed that, in the settlement, adult Ochlerotatus serratus (Theobald), Psorophora 68 cingulata (Fabricius), Hg. tropicalis Cerqueira and Antunes mosquitoes had been 69 naturally infected with the Oropouche virus, in addition to the typical acrodendrophilous 70 species captured in the soil. Further, a greater diversity of species was reported in the 71 forest edge environment when compared to the forest and peridomicile [12]. 3 bioRxiv preprint doi: https://doi.org/10.1101/2020.06.23.166694; this version posted June 23, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. 72 Mosquitoes are characterized by their flexible use of a wide variety of breeding 73 sites, from larges found at the soil level, to small pools of water stored in leaves in the 74 canopy of trees. Man-made objects are also perceived as potential breeding sites for 75 mosquitoes [13]. Immature Limatus durhamii Theobald mosquitoes, a species naturally 76 infected with the Guama virus, can develop in breeding sites ranging from tree holes to 77 landfill percolation tanks [14,15]. Immature forms of Anopheles species have been 78 recorded in artificial containers [16,17], including An. darlingi Root, which was found in 79 an artificial lagoon in the urban region of Manaus in the state of Amazonas [18]. 80 Studies of immature mosquitoes captured in artificial breeding sites located in 81 Amazonian environments are scarce. However, some authors [13,19–23] have indicated 82 that artificial breeding sites are preferred by immature mosquitoes of various species. 83 Due to the importance of sanitary conditions and the ecological evolution that has 84 led to the use of water containers for breeding by female mosquitoes, this work aimed to 85 identify mosquito species that colonize different types of artificial breeding places, 86 located in environments with different levels of anthropization within the state of 87 Amazonas. 88 Materials and Methods 89 Study site and sample design 90 The study was carried out in the Rio Pardo rural settlement, Presidente Figueiredo 91 Municipality, State of Amazonas, Brazil (Fig 1). The settlement is surrounded by a 92 continuous primary forest and presents a typical Amazonian climate, humid tropical as 93 per the Kopper classification. The human population of the region is comprised of 94 approximately 550 inhabitants, and economic activities include agriculture and livestock. 4 bioRxiv preprint doi: https://doi.org/10.1101/2020.06.23.166694; this version posted June 23, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. 95 Fig 1. Study area Geographical Information System. A - In different shades of grey; 96 South America, Brazil, and the municipality of Presidente Figueiredo. B - Delimitation 97 area of the Presidente Figueiredo municipality, pointing the agrovillage of Rio Pardo. C 98 - Rio Pardo agrovillage and, in prominence, roads where larvitraps were distributed for 99 immature mosquito collection. D - Location of collection points along agrovillage roads. 100 The area of the settlement is about 317 km², and includes roads, small villages, 101 wooden houses, gardens, and forest areas. The deforestation rate of the settlement 102 increased from 12.32% in 2008 to 19.79% in 2015. 103 The delimitation of the settlement area was done through IKONOSTM satellite 104 imagery. Eighteen collection sites were chosen, separated by buffer areas with a radius of 105 200 m. Sampling points were placed in forest, forest edge, and peridomicile 106 environments. 107 Collection of immature mosquitoes 108 Collections were carried out during four periods of 15 days each, during the 109 months of November 2017 and January and February 2018. For the collection of 110 immature mosquitoes, bamboo internodes, tires, and plastic containers were installed (Fig 111 2).