Effects of High Larval Density on Wing Shape Deformations of Culex pipiens (Culicidae: Diptera) via Geometric Morphometrics.

Populations of Culex pipiens, which is considered a primary vector of West Nile Virus, are not uniformly shaped, and hence, they are difficult to work on, not only because of the complex structure of the species but also due to the possible deformations caused by several factors like temperature, pH, parasite, and bacterial density. Larval density is another crucial factor. This study summarizes the effects of larval density in Cx. pipiens as a model of experimental semi-controlled ecomorphs by two different geometric morphometrics methods. The landmark-based method explains that dimorphism is clearly visualized in both the size and shape of the wings. It also shows that females and males have gradually traceable deformations. When the population reaches a high larval density, which is calculated as approximately 0.5 cm3/individual or, in other words, 1 larva/mL in Cx. pipiens, it can be considered a breaking point, where deformations in shape are observed through all study periods, indicating that it is effected separately and varies independently from the other factors. The wings become smaller in both sexes as the larval density increases. Similar results are obtained by Elliptic Fourier Analysis, which explains the difference in the contour of the wing, regardless of where the landmarks on the veins are located.