Mosquito fauna (Diptera: Culicidae) of the Eastern Region of Saudi Arabia and their seasonal abundance

During the period from March 2004 to February 2006, a mosquito (Diptera: Culicidae) survey was conducted in the Eastern Region of Saudi Arabia, and 25 species which belong to 5 genera: Aedes (1 species), Anopheles (13 species), Culex (9 species), Culiseta (1 species) and Uranotaenia (1 species) were collected. The mosquito species encountered were: Aedes caspius Palls, Anopheles cinereus Theobald, Anopheles coustani Laveran, Anopheles d’thali Patton, Anopheles fluviatilis James, Anopheles gambiae Giles, Anopheles multicolor Cambouliu, Anopheles pretoriensis Theobald, Anopheles rhodesiensis Lewis, Anopheles sergentii Theobald, Anopheles stephensi Liston, Anopheles subpictus Grassi, Anopheles superpictus Grasssi, Anopheles tenebrosus Donitz, Culex laticinctus Edwards, Culex perexiguus Theobald, Culex pipiens Linnaeus, Culex pusillus Macquart, Culex quinquefasciatus Say, Culex simpsoni Theobald, Culex torrentium Martini, Culex tritaeniorhynchus Giles, Culex univittatus Theobald, Culiseta longiareolata Macquart and Uranotaenia unguiculata Edwards. Among the mosquito larvae collected, Culex spp. were the most abundant (66.41%), followed by Ae. caspius (17.64%), Anopheles spp. (14.91%), U. unguiculata (1.03%) and Cs. longiareolata (0.01%). The study has shown that the pH and total dissolved salts have no significant effect on the distribution of mosquito larvae. Adult mosquitoes were collected throughout the year, but at different densities depending on the prevailing climatic conditions. The effect of temperature and rainfall on the seasonal abundance of adult mosquitoes in the study area is discussed. The study has shown that mosquitoes are widespread in the Eastern Region, and more studies on their ecology and biology are required before embarking on large scale control projects.