Comparing the Antennal Lobes of Two Forms of Culex pipiens Mosquito

Abstract

Mosquitoes are vectors for dozens of diseases worldwide, killing millions of people each year. Understanding how mosquitoes choose and locate their hosts is crucial for creating new techniques to prevent the spread of these diseases. Culex pipiens is a mosquito species found across several continents and is responsible for the spread of West Nile Virus. This species has two forms, Cx. pipiens form pipiens and form molestus, which feed on birds and mammals, respectively. This divergence of host preference within one species allows for the opportunity to compare the olfactory systems of both forms to discover how this host preference arises. In this study, I start by mapping the glomeruli in the antennal lobe of Cx. pipiens, which has not been mapped in previous research. I then compare the antennal lobes of the two forms of Cx. pipiens, specifically comparing the volumes of homologous glomeruli. The volume of the antennal lobe was found to be significantly larger in form pipiens than form molestus. One large and centrally-located glomerulus was determined to be significantly larger in form pipiens than in form molestus. Further research will determine how the difference between this glomerulus in forms molestus and pipiens relates to divergence in peripheral nervous system structure and host preference development.