Bionomia de la població d’Aedes albopictus de Palma de Mallorca

Abstract

[eng] Aedes (Stegomyia) albopictus (Skuse, 1894), commonly known as the Asian tiger mosquito, is an exotic highly invasive species that was recorded for the first time in Spain in 2004 and in Mallorca in 2012. Currently, it is widely present in the Mediterranean east coast of mainland Spain and all the islands of the Balearic archipelago (Spain). Most studies involving this species in the region have been focused in surveillance and control methods, consequently there is a lack of microevolutionary studies for Ae. albopictus. Unveil patters of sexual dimorphism in Ae. albopictus populations can provide value information about their ecology and behavior and how they react to the unique selective pressures found in the Balearic Islands. Taking that into account, the goal of this study was to investigate the patterns of sexual dimorphism and bionomic parameters of Ae. albopictus populations from the Balearic Islands and determine if males are reacting to the selective pressures differently than females. For this, mosquito eggs where collected from the field using oviposition traps and reared in laboratory conditions where different bionomic variables were daily measured (i.e. % egg hatching, larvae and pupae development). In order to study morphometry of males and females, once adults emerged from pupae, the left wing of each adult mosquito was removed and mounted on a microscope slide with a cover slip. The wings were then photographed under 50x magnification and 18 landmarks were digitized using TpsDig V1.40 software. Subsequently, to explore the degree of wing shape dissimilarity between males and females were analyzed using MorphoJ 1.06d software. During autum 2017 we have been collected 361 Ae. albopictus eggs. From them, the 5,54% has been eclosed. In spring 2018, we have been collected 604 and obtaining an eclosion rate of 25,31%. Our results indicated a clear pattern of sexual dimorphism on the wing shape of Ae. albopictus specimens when analyzed by the cross-validated classification test. Males were correctly distinguished from females with an accuracy of 84% i females from males 75% (P = 0.0009). As well as, we have observed a seasonal pattern variation. These results are in agreement with the canonical variance analysis showing a total segregation of males and females. Collectively, our results are suggesting that selective pressures may be affecting males differently than females.