Aedes mosquitoes in the Republic of the Sudan, with dichotomous keys for the adult and larval stages

Abstract

ABSTRACTDescriptions of the mosquitoes of the Republic of the Sudan are mostly limited to works published more than 60 years ago. Khartoum State in central Sudan, which encompasses the capital city, has experienced many outbreaks of diseases caused by mosquito-borne pathogens, including Rift Valley fever. In this paper we focus on the composition of Aedes mosquitoes in high-risk areas in and around major agricultural projects. This is based on longitudinal surveillance of adults and larvae during the hot dry and rainy seasons in 2013. A total of 630 adult female mosquitoes were collected. Anopheles mosquitoes were the most abundant (n = 456, 72.4%), followed by Culex (n = 96, 15.2%) and Aedes (n = 78, 12.4%). Only three Aedes species were identified: Aedes caballus (n = 38, 48.7% of the Aedes), Aedes vexans arabiensis (n = 30, 38.5%) and Aedes caspius (n = 10, 12.8%). A total of 42,549 larvae were collected. Aedes larvae were the most abundant (n = 30,936, 72.7%), followed by Culex (n = 9656, 22.7%) and Anopheles (n = 1957, 4.6%). The Aedes larvae included Ae. caspius (n = 21,957, 71.0% of the Aedes), Ae. vexans arabiensis (n = 5577, 18.0%), Aedes quasiunivittatus (n = 107, 0.3%), Aedes dentatus (Theobald) (n = 204, 0.7%) and 3091 unidentifiable larvae (10.0%), denoted as Forms X, Y and Z. We discuss the bionomics of the four identified species of Aedes and provide updated keys for the identification of the mosquito genera and the larvae and adults of the Aedes species recorded from the Republic of the Sudan.