MACROPHYTES

Dipterans are excellent indicators of water quality; hence, they are routinely used as bioindicators during monitoring of aquatic ecosystems. The study was therefore, executed to investigate the physico-chemical water quality and dipteran aquatic insect larvae community. Both water and benthic samples were collected between August 2021 and January 2022 at four designated sampling stations along the Okhuahie River at Ikpe in Ikpoba-Okha Local Government Area of Edo State, Nigeria, using standard procedures. A total of 22 physiochemical parameters were determined and measured. Among the physical and chemical parameters, Flow rate, Dissolved oxygen, and Phosphate showed highly significant differences (P<0.001) across the stations. A total of 3 taxa comprising 857 species were recorded. Abundance was highest in station 3 consisting of 146 individuals and the lowest in station 2 consisting of 77 individuals. The dominant taxon is Chironomid (98%), Culex (1.2%) and Tanyderidae (0.3%). Culex consisted of just 1 species and 11 individuals, Tanyderidae of 1 species and 3 individuals, whereas Chironomid comprised 5 species and 843 individuals. The diversity indices showed that station 3 was more diverse followed by station 4, while dipteran species in station 2 was least diverse. Culicidae and Tanyderidae showed positive critical correlation to sulphate and turbidity. The overall abundance showed no significant difference (p > 0.05) for all the four station. This study proved that Okhuaihe River is unperturbed and the Dipteran encountered are characteristics of a tropical freshwater habitat.