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Rapid diversification is a way of responding to environmental change for freshwater organisms. This work examined the physicochemical changes and abundance of freshwater snails in Anambra River (Nigeria) during the rainy season. Field studies were conducted fortnightly from June to August 2019 at three stations of the river namely: Otuocha (station I), Otunsugbe (station II), and Ukwubili (station III) about 8.35 kilometers apart from each other. A scoop net of 2 cm mesh size and handpicking was used to sample freshwater snails randomly and water samples were taken to the laboratory for physicochemical analysis. A total of 896 freshwater snails belonging to 6 species (Afropomus balanoidea, Pomacea maculata, Lymnea stagnalis, Lanistes ovum, Pila wernei, and Saulea vitrea) were collected. Pomacea maculata was the most dominant species with a relative abundance of 45.87 %, while Saulea vitrea was the least dominant species with a relative abundance of 2.34 %. There was a significant negative correlation between dissolved oxygen and Pomacea maculate (r = –0.877, p = 0.002) and a positive correlation between dissolved oxygen and Stagnalis lymnea (r = 0.840, p = 0.005). The diversity of species was highest at Otuocha (1.171) followed by Ukwubili (1.133) and Otunsugbe (0.856) with average mean temperatures of (23.1 ±0.1) °C, (27.30 ±0.00) °C, and (26.80 ±0.03) °C respectively. The distribution of freshwater snails was influenced by the physicochemical variability of Anambra River during the rainy season. Therefore, further studies for a longer time and different seasons to examine the impact of physicochemical changes on the snail distribution are encouraged.

Butterflies are creatures of nature with great economic importance as pollinators and bio-indicators. This study provides checklist of butterfly species present in Zoological and Botanical gardens of University of Nigeria, Nsukka and was conducted for three Months. Butterflies were sampled twice a week between 7.00 -10.00am from May to July 2019; using sweep net along existing transects within the gardens. Non-invasive method was adopted, butterflies were captured, photographed and released. Photographed samples were identified to species level by cross matching with relevant keys. A total of 91 butterflies belonging to 16 species, 10 genera and 3 families were sampled. Alpha diversity test showed a significant difference (p<0.05) in terms of Relative Abundance, Diversity and Dominance of butterfly species between the two gardens. The Botanical garden had Relative Abundance of 63.73%, Dominance of 0.23 which was higher compared to Zoological garden which had 36.16% and 0.10; but these was contrary to species diversity where Zoological garden was more diverse (H1=2.48) than botanical garden (H1=1.82). The differences observed could be attributed to variations in vegetation composition.

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