The Land Snail Fauna of a Square Kilometer Patch of Rainforest in Southwestern Cameroon: High Species Richness, Low Abundance and Seasonal Fluctuations

Winter, A. J. de & Gittenberger, E.

Publication Date: 1998

About this Item

Systematic sampling of a single square km patch of rather acidic, undisturbed, fairly uniform Cameroonian rainforest during two different rainy seasons yielded 97 species of land snails, belonging to at least 12 families. Up to 45 species were collected within a single sampling site of 20 m X 20 m during a single visit, and up to 51 during two visits in different seasons. This might be the world's highest sympatric land snail diversity reported to date. Variation in species composition among the sampling sites appeared to be largely random, and not due to geographic or ecological replacement. Three (super)families make up 86% of the species, the carnivorous Streptaxidae (34%) being the most diverse. Overall snail abundance was rather low, and many species were rare. Of 64% of the species, the abundance was less than 1% of all specimens (2,654) collected. A substantial difference was observed in overall snail abundance between the two sampling periods. About 27% of the species were uniquely found in one of the two sampling periods, and many species differed more than 50% in relative abundance between these seasons. At least 27% of the species were largely or completely arboreal, and 19% were found to live both on the ground and in the vegetation; 46% of the species appear to be confined to the ground, and of 7% insufficient information was available. Major adult shell dimensions (height or diameter) range between approximately 1 and 165 mm, but the vast majority (74%) of species had adult shells smaller than 10 mm. The shell height:diameter ratio distribution is bimodal, but differs from those previously reported for other faunas by relatively many "globose" (H/D 0.8-1.2) and very tall (H/D 2.8-4.4) shells. The distribution of neither shell size nor shell shape differed between ground-dwelling and (partly) arboreal species. 20 pp., 5 figs, gr. 8.

Seller Inventory # W19851

Bibliographic Details

• Title: The Land Snail Fauna of a Square Kilometer Patch of Rainforest in Southwestern Cameroon: High Species Richness, Low Abundance and Seasonal Fluctuations
• Publication Date: 1998