Carolina Mangudo

Tree holes as larval habitats for Aedes aegypti in public areas in Aguaray, Salta province, Argentina

1Instituto de Investigaciones en Enfermedades Tropicales, Sede Regional Orán, Universidad Nacional de Salta, Alvarado 751 Orán, 4530 Salta, Argentina 2 Instituto de Investigación en Energías no Convencionales, Universidad Nacional de Salta, Av. Bolivia 5150, 4400 Salta, Argentina 3Centro de Relevamiento y Evaluación de Recursos Agrícolas y Naturales, Facultad de Ciencias Agropecuarias, Cátedra de Ecología, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba

Tree holes as larval habitats for Aedes aegypti in urban, suburban and forest habitats in a dengue affected area.

Aedes aegypti (L.) (Diptera: Culicidae), the main vector of dengue and urban yellow fever in the world, is highly adapted to the human environment. Artificial containers are the most common larval habitat for the species, but it may develop in tree holes and other phytotelmata. This study assessed whether tree holes in San Ramón de la Nueva Orán, a city located in subtropical montane moist forest where dengue outbreaks occur, are relevant as larval habitat for Ae. aegypti and if the species may be found in natural areas far from human habitations. Water holding tree holes were sampled during 3 years once a month along the rainy season using a siphon bottle, in urban and suburban sites within the city and in adjacent forested areas. Larvae and pupae were collected and the presence and volume of water in each tree hole were recorded. Finding Ae. aegypti in forested areas was an isolated event; however, the species was frequently collected from tree holes throughout the city and along the sampling period. Moreover, larvae were collected in considerably high numbers, stressing the importance of taking into account these natural cavities as potential reinfestation foci within dengue control framework.

Notes on the Occurrence and Habitats of Sabethes purpureus in Salta Province, Argentina

Abstract The finding of Sabethes purpureus larvae and pupae in tree holes both in urban and forest environments in San Ramón de la Nueva Orán, Salta Province, Argentina, is reported, together with information on the larval habitat. Tree holes were sampled monthly from January to March or April of 2011, 2012, and 2013 along sidewalks, in public access areas, and in 3 sites within forested areas outside the city, selected along an urban gradient in Orán. Sabathes purpureus was most frequently found in low numbers and with other mosquito species. A higher proportion of tree holes was positive in the urban compared to the forest environment, although there were no significant differences in abundances or densities per hole. To our best knowledge, this paper reports the species for the first time breeding in an urban environment, and extends its geographical distribution from the Atlantic and Paranaense forests to the Southern Andean Yungas in northwestern Argentina.

Descriptions of Pupae of Three Psychodinae Species (Diptera: Psychodidae) from Argentina

Abstract. The pupae of Alepia montana Bravo, Alepia truncata Bravo, Lago et Castro and Psychoda simillima Tonnoir, belonging to the subfamily Psychodinae, are described and illustrated. The pupae of A. montana and A. truncata were collected in tree holes in the city of San Ramón de la Nueva Orán, Province of Salta and the pupa of P. simillima in small pool on the nameless stream near El Hoyo city, Province of Chubut, Argentina. The pupa of P. simillima is similar to other pupae of the genus Psychoda Latreille, being distinguished by some features in the last segment and by respiratory trumpet. These are the first pupae described of any species of the genus Alepia Enderlein.

Vegetation Cover and Microspatial Distribution of Sand Flies (Diptera: Psychodidae) in an Endemic Locality for Cutaneous Leishmaniasis in Northern Argentina

Abstract The sand fly fauna in Hipólito Yrigoyen, Argentina, a locality where cutaneous leishmaniasis cases occur, was surveyed with zones of higher abundance of sand flies correlated to vegetation cover estimated through normalized difference vegetation index (NDVI). Sand flies were collected with 10 CDC traps during six nights, from December 2009 to January 2010. A map was built of expected sand flies abundance in which levels of NDVI were categorized. In total, 1,392 Phlebotominae (Diptera: Psychodidae) specimens were collected, comprised of the following species: Nyssomyia neivai (Pinto 1926), Migonemyia migonei (França 1920), species of the cortelezzii complex (Brèthes 1923), Evandromyia sallesi (Galvão & Coutinho 1940), and Psathyromyia shannoni (Dyar 1929). Positive correlations were found between the abundance of sand flies and the NDVI (P < 0.05) for buffer areas of <150 m radii from the trap location points, i.e., the sand fly abundance was greater where vegetation cover and density were greater. In this context, plant cover should be taken into account to prioritize surveillance and control areas within the program of sand flies control in northern Argentina.

The Immatures of Culicoides trilineatus (Diptera: Ceratopogonidae) Potential Vector of the Bluetongue Virus

Abstract The fourth instar larva and pupa of Culicoides trilineatus Fox (Diptera, Ceratopogonidae), a species considered as potential vector of the bluetongue virus in Central and South America, are described, illustrated, and photomicrographed for the first time by using binocular, phase-contrast, and scanning electron microscopy. The immatures were collected by using a siphon bottle in tree holes in Salta Province, Argentina, transported to the laboratory, and there reared to the adults emergence. They are compared with the immatures of Culicoides debilipalpis Lutz (Diptera, Ceratopogonidae), another Neotropical species that develops in tree holes. Details on larval biology and habitat are given.

Factors Related to Aedes aegypti (Diptera: Culicidae) Populations and Temperature Determine Differences on Life-History Traits With Regional Implications in DiseaseTransmission

Abstract Aedes aegypti (L.) (Diptera: Culicidae) is a vector of many medically significant viruses in the Americas, including dengue virus, chikungunya virus, and Zika virus.Traits such as longevity, fecundity, and feeding behavior contribute to the ability of Ae. aegypti to serve as a vector of these pathogens. Both local environmental factors and population genetics could contribute to variability in these traits. We performed a comparative study of Ae. aegypti populations from four geographically and environmentally distinct collection sites in Argentina in which the cohorts from each population were held at temperature values simulating a daily cycle, with an average of 25°C in order to identify the influence of population on life-history traits. In addition, we performed the study of the same populations held at a daily temperature cycle similar to that of the surveyed areas. According to the results, Aguaray is the most outstanding population, showing features that are important to achieve high fitness. Whereas La Plata gathers features consistent with low fitness. Iguazu was outstanding in blood-feeding rate while Posadass population showed intermediate values. Our results also demonstrate that climate change could differentially affect unique populations, and that these differences have implications for the capacity for Ae. aegypti to act as vectors for medically important arboviruses.

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

Aedes aegypti L. (Diptera: Culicidae) is a mosquito broadly found in tropical and temperate areas of the world. It is the main vector of dengue, chikungunya, zika and yellow fever (urban cycle), among other viruses. Aedes aegypti immatures develop in water holding containers, and frequently use artificial containers in urban settings as larval habitat. Ovitraps are artificial oviposition sites, a tool developed for mosquito population surveillance and to assess effectiveness of control measures. The preference for different oviposition substrate materials was assessed in the field, in two localities of Salta province, northern Argentina, where dengue outbreaks are frequent. The proportion of positive traps did not differ between oviposition substrates. However, higher numbers of eggs were laid in cotton fabric and velour paper, which were better than wooden paddle and blotting paper if the aim was to maximize the numbers of eggs collected. The results also evidenced that substrate preference for oviposition did not differ between geographic regions.

Snail shells as larval habitat of Limatus durhamii (Diptera: Culicidae) in the Yungas of Argentina

The shells of dead snails collect water from rainfalls producing aquatic microenvironments called gastrotelmata. These habitats are small and hold simple detritus based on animal communities, being rotifers and culicids the most studied. Although a high diversity of aquatic microhabitats has been reported as larval habitats of mosquitoes in Argentina, the shell of snails has not been investigated yet. We report the shells of three species of native Megalobulimus genus as larval habitats of a neotropical mosquito and suspected vector of bunyaviruses, Limatus durhamii, and describe these microhabitats in the Yungas forest of Argentina.

New genus of Psychodinae (Diptera, Psychodidae) from Argentina

Adults (male and female) and pupae of Chuspilepia saltenia gen. nov., sp. nov. were collected in tree holes in the Yungas rainforest, near San Ramon de la Nueva Oran city, Salta province, Argentina. It was not possible to place this new species in any known genera using the available keys and published descriptions, thus a new genus is proposed for the Neotropical region of Argentina.