Diversity of Weevils (Coleoptera) in Marahan, Marilog Forest Reserve, Southern Mindanao, Philippines

Abstract

Fieldworks were conducted last January to March, 2019 to collect and record species of weevils at Sitio Matigsalug, Marahan, Marilog Forest Reserve, Marilog District, Mindanao, Philippines. Standard sampling techniques such as belt transect and op-portunistic sampling were conducted in the established 2 kilometers transect to sur-vey the agroforest and montane ecosystems with elevations of 800-950 masl and 1,000-1,300 masl, respectively. A total of 228 individuals belonging to 2 families and 22 species of weevils were recorded, all of which are only known from forest and mountain ecosystems of Mindanao. Metapocrytusis the most encountered genus with 12 species. The montane forest had higher species richness with 15 species but with lower species abundance of 34 individuals compared to the agroforest ecosys-tem with 13 species and 194 individuals. Seven (7) species are common in both sites. Plant associates and behavior of the observed weevils were also noted which include 22 species of ferns and flowering plants. Other than perching behavior, spe-cies are also observed copulating, feeding and mostly hiding in abaxial part of leaves. As flightless beetles with high vulnerability for predation by other insectivo-rous species, the observations gathered will help in understanding their behaviors for survival. Despite of high species richness and abundance, anthropogenic disturb-ances such as agricultural activities are on-going which extend towards the montane forest in the area. Conservation initiatives must be implemented to protect the re-maining endemic and rare species of flora and fauna.

Keywords

• endemic
• marilog district
• metapocyrtus
• montane forest
• pachyrhyn-chus