Species composition of dung beetles in the primary and secondary forestes at Ton Nga Chan Wildlife Sanctuary

The species composition of dung beetles in primary forest and secondary forest at Ton Nga Chang Wildlife Sanctuary, Songkhla province, southern Thailand, was compared. Traps baited with pig dung were placed along line transects running through the two forest types. Species diversity and abundance of dung beetles were examined every 2 months from April 1999 to May 2000. Species diversity of dung beetles was significantly higher in the primary forest than in the secondary forest. Seven out of 20 species were found exclusively in the primary forest, namely Microcopris reflexus, Oniticellus tessellatus, Onthophagus near pilularius, O. taeniatus, O. ventralis, O. sp.3 and O. sp.4. Differences in forest structure, native animals present, and physical factors were suggested to be the factors determining species composition in the two forests. More individuals were trapped in the dry season than in the wet season in both forest types. However, seasonal effects on species diversity were not found. Tiniocellus sarawacus and Microcopris reflexus, were recorded for the first time in Thailand. Onthophagus sp.1 and O. sp.2 are expected to be new to science.