Aedes japonicusis is a mosquito species native to Korea, Japan, Taiwan, southern China and Russia. It is not considered an important disease vector although there is concern that this species may become a pest problem or be involved in the transmission of North American arboviruses such as West Nile virus, La Crosse virus, as well as Japanese B. The mosquito was first reported in the Unites States in 1998 and since then it spread into 30 states and was occasionally sighted in Ontario, Canada. It is also widespread in Europe.
The success of the invasion of Aedes japonicus is has been due to a number of factors including its ability to withstand long distance dispersal and winter temperatures in our regions, as well as its high tolerance to organic concentrations in various forms of natural and artificial containers.
A team of researchers from Simon Fraser University and Culex Environmental, found Aedes japonicus for the first time in Western Canada and just published on their find. Several specimens were obtained in suburbs of Vancouver.
Species identification was done based on morphology of reared adults as specimens were obtained in several larval stages. Although I don't doubt the accuracy of the identifications of the authors I wonder why molecular methods of species identification such as DNA Barcoding are not already used in such cases. BOLD has more than 80 reference sequences for Aedes japonicus alone. It would safe the time and effort used to rear the larvae to adulthood and given all labour and procedures involved it would likely cost about the same. Furthermore, it would allow more widespread testing to survey the extent of an invasion and to monitor its spread. The workforce that can reliable identify Aedes species based on morphology is certainly limited.