Distribution of living larval Chironomidae (Insecta: Diptera) along a depth transect at Kigoma Bay, Lake Tanganyika: implications for palaeoenvironmental reconstruction

We analysed the distribution of living larval Chironomidae (Insecta: Diptera) along a depth transect (0–80 m water depth) at Kigoma Bay in Lake Tanganyika (East Africa) to explore the ecological indicator value of Lake Tanganyika’s midge fauna and to delineate the habitat preferences of resident larvae. Additionally, by comparing the taxonomic resolution reached in live versus fossil chironomid studies in this lake, we appraised the general information content of African fossil chironomid assemblages and, therefore, the quality of African chironomid-based palaeoenvironmental reconstructions. We found 141 chironomid specimens, representing two Tanypodinae, one Orthocladinae and 13 Chironominae (seven Chironomini and six Tanytarsini) taxa. All of these are conspecific to larval types encoun-tered in subfossil collections from Lake Tanganyika or smaller East African lakes, but their differential diagnoses are updated here to include exoskeletal elements that are generally better preserved on live specimens. The chironomid assemblage collected in the Kigoma Bay depth samples is dominated by a few species of chironomine detritus and algae feeders, concentrated in areas of high macrophyte density. Additionally, there is a small component of tanypodine predatory taxa, along with several relatively rare, possibly habitat-specialist