Mosquito larval habitat ecology in the cold arid Patagonia region of Argentina

Knowledge of mosquito ecology in the southern Argentine Patagonia region remains restricted mainly to geographic distributions and some habitat descriptions.  There has been no comprehensive study of the ecology of larvae in this region. This study focuses on associations of environmental and physicochemical conditions in aquatic habitats with abundances of mosquito species that colonized those habitats. Twenty-six mosquito larval habitats were survey in Patagonia (38-54°S; 65-77°W; 14-1,163 m above sea level), during December 2013-January 2014. Habitats were mainly natural temporary pools located in mountain and steppe environments. Variables recorded at each site showed the following ranges. Water temperature: 10.2-36.5°C, pH: 4.6-9.5, conductivity: 16.2-56,500µS×cm^-1, salinity: up to 21.1‰, total dissolved solid: 11.8-28,400mg×l^-1, alkalinity: 63.4-18,180µEq×l^-1, dissolved oxygen: 1.3-19.3mg×l^-1, aquatic plant cover: 1-80%, mean water depth: 2.5-43.3cm, area: 0.01-693.5m². Seven mosquito species belonging to two genera were identified. Culex apicinus was the most abundant species (48.2%) restricted to northern Patagonia, associated with high values of water depth. It was followed by Cx. acharistus (22.5%) and Ochlerotatus albifasciatus (17.6%), which were associated with high values of alkalinity and percentage of plant cover, respectively. Less abundant species were Cx. brethesi (7.7%), Cx. eduardoi (2.6%), Cx. dolosus (1.4%), and Cx. (Alm.) tramazaiguesi (0.1%). This last species was associated with higher conductivity and salinity values, and represented a new record for Neuquén province. The present study enhances our knowledge of mosquito larval habitat ecology under extreme environmental conditions of Patagonia region.