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Abstract
Mouth parts deformities in chironomid larvae are considered as indicators of environmental stress in aquaticsystems caused by water and sediment pollution such as heavy metals, pesticides as well as organiccontamination. Fourth instar chironomid larvae were collected from two sites (SI and SII) located in the RiverNile, Sohag Governorate, Egypt. The chironomid community of the two SI and SII was dominated by
Dicrotendipes nilophil
(Diptera: Chironomidae)
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The percentage numbers of chironomid larvae with deformedmouthparts were 29% (SI) and 14% (SII)
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Although there were no significant differences in the sediment metalconcentrations between the two sites, significant differences were recorded among the metal concentrations