Diversity of Land Snails in the Karst Areas of Sta. Teresita, Cagayan Province, Luzon Island with Notes on New Distribution Records

Abstract

Malacofaunal research in a karst ecosystem is very limited not only in the northern region of Luzon Island but in the entire Philippines amidst extensive habitat disturbance and destruction. To address this, the diversity and abundance of land snails in the karst areas of Santa Teresita, Cagayan Province were determined. A total of 25 5 x 5 m2 quadrats were randomly set in five stations in the karst landscape. A total of 1206 land snails comprising 45 species under 36 genera representing 17 families were sampled. Camaenidae was the most represented family with 10 species. Luzonocoptis antennae constituted 25.1% of the total number of samples (303 individuals) and was the most abundant species in all stations. Of the 36 genera, five are new records in the Philippines. Several karst endemics and introduced species were recorded. Diversity indices showed diverse land snail fauna with Shannon-Weiner diversity index (H’) of 2.80, with evenness (J’) of 0.36 and dominance index of (D’) of 0.11. Species accumulation curve (SAC) showed late asymptote with a completeness ratio of 0.92. The study demonstrated that land snails in Sta. Teresita, Cagayan Province are rich and diverse. It is very important to recognize Sta. Teresita as priority sites for malacofaunal conservation, and consider the further evaluation of these sites to be designated as a protected area.