MOSQUITOES (DIPTERA: CULICIDAE) OF THE WESTERN COASTAL AREA, KINGDOM OF SAUDI ARABIA: SPECIES COMPOSITION, ABUNDANCE, DIVERSITY AND MEDICAL IMPORTANCE.

An entomological survey was undertaken for two years to update the mosquito fauna of the 3 regions (Mecca, Al Madinah and Tabouk), of the western coast, Kingdom of Saudi Arabia. Six localies representing such Regions (lhif, Mecca, Jeddah, Yanbu, Daba and Haql) were sampled for larvae and adults. Nineteen soecies of six genera were reported of which genus Culex (57.89% sp.) were the most commo6, followed by Anopheles (21.05%) and Stegomyia, Ochlerotatus, Aedes and Culesita (5.26% each). Three species (Cx. sitiens, Cx. torrenlium and Am. v. arabiensis) were new reports in study area. A total of 10930 larvae and 33108 adults were collected of which those representing genus Culex were predominating (92.74% larva, 93.46% adult). Of the reported species, Cx. quinquefasciatus (47.11% larva, 57.52% adult) and Cx. pipiens (22.24% larva, 27.42% adult) Were the common ones. Both Taif and Tabouk reported the highest number of species (13 sp., 68.42%), followed by Jeddah (12 sp., 63.16%), Mecca (10 sp., 52.63%) and Yanbu (8 sp., 42.11%). Tabouk represented the maximum diversity with the highest Simpson index (1-D=0.65) and Shannon index (H=1.25) followed by Taif (1- D=0.54, H=1.01). Per sampling site, Jeddah reported the highest number of larvae (313.70), and Mecca had the highest adult number (670.18). A complete list of mosquito fauna of the western coast including 35. spp. was presented based on the present and previous surveys. The role of the reported mosquito species as disease vectors was discussed. The study concluded that the diversity and abundance of the different mosquito species, among which several vectors of diseases mainly malaria, Rift Valley fever, lymphatic filariasis and dengue fever may pause a risk of transmission and more spread of such disease in this part that contains the holy places which are visited all year round by millions of people from several countries.