Abstract:
Most of the entomological surveys target only the vector mosquitoes and distribution of
different species were limitedly documented. So, this study was designed to understand
diversity, distribution and co-occurrence of Aedes species through rural and urban settings in
Kalutara district. Palindanuwara and Walallawita were the selected rural areas and Panadura
and Wadduwa were the selected urban areas. In every two month from January 2019 to
December 2021 larval survey was carried out. For each survey 20 premises including houses,
institutions, open areas and croplands were examined. Aedes mosquitoes were identified upto
species level based on morphology using taxonomic review. Species diversity was calculated
by Shannon Weiner Diversity Index (H) and Simpson Index of Diversity (1-D). During the
study 4238 Aedes mosquito larvae belonging to 12 species were identified. Those species were
Ae. (Collessius) sp.1 (n=336, 7.93%), Ae. (Downsiomyia) albolateralis (n=28, 0.66%), Ae.
(Do.) sp.1 (n=4, 0.09%), Ae. (Fredwardsius) vittatus (n=283, 6.68%), Ae. (Hulecoeteomyia)
chrysolineatus (n=243, 5.73%), Ae.(Stegomyia) aegypti (n=441, 9.46%), Ae.(St.) albopictus
(n=2825, 66.66%), Ae.(St.) krombeini (n=53, 1.25%), Ae.(St.) w-albus (n=27, 0.64%), Ae.(St.)
sp.1 (n=10, 0.23%), Ae.(St.) sp.2 (n=7, 0.17%), Ae.(St.) sp.3 (n=21, 0.5%). There was a
significant difference in the species richness (p = 0.0006, f = 12.744) and species diversity in
terms of H (p = 0.012, f = 6.530) and (1-D) (p = 0.043, f = 4.248). Aedes aegypti was not found
in rural sites (p = 0.001, f = 11.483). Co-occurrence of Aedes species more frequent in rural
areas (n=35, 65%) compared to urban settings (n=19, 35%). Aedes aegypti and Ae. albopictus
co-occurrence were more common in urban areas (n=13, 68%) and Ae. albopictus and Ae.
chrysolineatus co-occurrence were more common in rural areas (n= 14, 40%). So, before
implementing vector control measures it is better to be deliberated those variations.
