Abstract

Terrestrial snails can act as critical indicators in response to climatic variables, including global warming, and thus are highly qualified for the use in ecosystem preservation. Some Species are endemic to the region and are yet to be fully discovered and the continuous destruction of the forest could lead to land snail’s extinction. A total of 2461 land mollusc individual representing 27 species belonging to 7 families were recorded from 30 plots in the study sites. The three most abundant families, declining in rank order were Urocyclidae, Streptaxidae and Archatinidae, together representing 90.82% of the total number of molluscs collected from the sites. Species count found in Cross River National Park (Nkunaya Station and Buffer Zone) and Idanre Hills Forest Reserve from the plots are show where family Streptaxidae from Cross River National Park (Nkunaya Station Zone) had the highest percentage of species, followed by family Subulinidae (Cross River National Park “Nkunaya station Zone”) and Urocyclidae and Archatinidae from Cross River National Park (Nkunaya station Zone), Idanre Hills Forest Reserve and Cross River National Park (Buffer Zone). The families with the least species were Aillyidae, Cyclophoridae and Succineidae respectively. The total number of species collected from the three sites. Gymnarion sp. (Family: Subulinidae) had the highest number of species collected of 997 individuals from the sites, followed by Gonaxiscamerunensis.

Margalef’s species richness index (d) showed the richest plot as plots 8 from Idanre Hills Forest Reserve with a value of 3.34, followed closely by plot 10 from Cross River National Park (Buffer Zone) with a value of 3.18. Shannon-Weiner’s diversity index (H1) showed a relative uniformity of data with the highest value of 2.26 for plot 10 in Cross River National Park (Buffer Zone) as the most diverse plot, while the least value of 1.11 was from plot 10 in Cross River National Park (Nkunaya Station Zone). Evenness (€) showed the most equitable plot to be in plot 10 in Cross River National Park (Buffer Zone) with a value of 0.96, while the lowest equitable plot was plot 5 in Cross River National Park (Nkunaya Station Zone) with a value of 0.26. Chao 2 and Jackknife estimator was 22.13 and 21.13 of all samples collected, respectively. Chao 2 and Jackknife estimator was 20.35 and 22.60 of all samples collected, respectively. Idanre forest reserve Whittaker Index was 1.35, which indicated low differentiation among plots.

Osiele, V.O.,, Arimoro, F.O., Ayanwale, A.V., Yahaya, T., Anani, A.O., Ronald, W.I.A., Danladi, P., 2024. Seasonal species composition and richness of terrestrial mollusks in Protected (Cross River National Park) Cross River State and Idanre Forest Reserve Ondo State. Plant Health Archives, 2024, online first.