Trichoptera of the lower Niger delta, Nigeria: species composition and relative abundance

Abstract

Trichoptera was collected twice weekly for one year (December 1998 – November, 1999) from a light trap at a jetty on the New Calabar River of the Niger delta, Nigeria to provide information on species composition and seasonal changes in relative abundance of Trichoptera in the lower Niger. Results indicated that six families (Hydroptilidae, Philopotamidae, Hydropsychidae Dipseudopsidae, Ecnomidae, and Leptoceridae) were represented. Fifteen taxa of these families were identified. Lepoceridae was the most diverse (six taxa) and the most abundant (60.42% of the total trichopterans collected). The least abundant family was Hydropsychidae which accounted for only 0.17% of the total collected. One specimen of Polymorphanisus elizabethae Navas (Hydropsychidae) was recorded. Relative abundance was higher in the dry than the rainy season. Some species were multivoltine.

Keywords: trichoptera, light trap, species composition, relative abundance, lower Niger

Tropical Freshwater Biology 2003/2004 Vol. 12/13: 1-7