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Aquatic insects inhabiting Okhuo River, in a tropical forest near Benin City, Southern Nigerian, were studied between January and December 2006 to determine the taxa composition, diversity, EPT index, relative proportions of the various groups and hence the pollution level of the waterbody. Three stations were selected and sampled monthly using the kick sampling technique. A total of 3235 individual aquatic insects belonging to 24 taxa distributed among 23 genera in six orders were collected. The insect orders occurred in the following order of dominance: Ephemeroptera > Odonata > Coleoptera > Diptera > Plecoptera > Tricoptera. Based on the diverse composition of the community dominated by organisms intolerant of organic enrichment, and the high diversity and EPT index, water quality in Okhuo River is not significantly degraded. Community composition varies seasonally, with a trend toward a declining proportion during the rainy season and increasing proportions during the dry season. Aquatic insect composition in Okhuo River compares favourably with those in similar, relatively undisturbed forest streams and rivers in Nigeria, but the diversity and proportional distribution of taxa vary considerably between streams. [ABSTRACT FROM AUTHOR]

A survey of the hemi-epiphytes and other herbaceous facultative epiphytes was performed in Kibale National Park. A total of 100 major host trees were sampled in detail by a canopy-based single rope technique. A total of thirteen families, thirteen genera with 24 species were found being dominated in terms of species by the family Moraceae with nine species. The most common Ficus species were F. sasibarica and F. conracii, while the herbaceous facultative epiphytes had Rhipsalis baccifera, Peperomia manni and P. tetraphylla as the most common. Correlation analysis revealed no relationship between basal area and the Ficus species. The herbaceous facultative epiphytes increased significantly with increase in the host basal area. Ficus species and the herbaceous facultative epiphytes preferred the ‘base’ and ‘mid’ branch zones of the host trees characterized by a narrow range of vertical distribution in both the logged and un-logged forests. Most species were found in the ‘light’ and ‘heavy’ humus type of substrates. There was a tendency for the logged forests to have more hemi-epiphytes and the herbaceous facultative epiphytes than the un-logged forest types. [ABSTRACT FROM AUTHOR]