Diversity And Vertical Distribution Of Geometrid Moths (Lepidoptera: Geometridae) In Three Forest Types In Sarawak

• Main Author: Foo, Iris Bee Bee
• Format: Final Year Project Report
• Language: English
• Published: Universiti Malaysia Sarawak, (UNIMAS) 2009
• Subjects: QL Zoology
• Online Access: http://ir.unimas.my/id/eprint/34084/2/Iris%20Foo%20ft.pdf; http://ir.unimas.my/id/eprint/34084/

Tropical geometrid moth communities are able to reflect ecological differences between habitats and this make them as a suitable biological indicator group in the study of biodiversity. Diversity and vertical distribution of geometrid moths, were investigated in a peat swamp forest, a lowland forest and a kerangas forest, using modified Pennsylvanian light traps conducted for a total of ten nights from September to December 2008. Light traps were installed in understorey and upperstorey, and left to function from 1800 hrs-0600 hrs the following day. A total of 252 individuals comprising of 55 species from six subfamilies of the geometrid moths were recorded. The Shannon-Weiner diversity indexes for the geometrid moths collected from peat swamp forest, lowland forest and kerangas forest were 4.324, 3.882 and 3.782 respectively. The Shannon-Weiner diversity indices at the upperstorey in these three forest types were surprisingly higher than the understorey with a significant difference between these two levels. This result stands in contrast to previous studies showing more diverse_ geometrids collected in the lower level. All the three forest types were characterized by the dominance of the subfamily Ennominae which was recorded as the most abundant moths at both the understorey and upperstorey. The four commonest species collected in this study were Calletaera subexpressa o (Ennominae), Craspedosis arycandata C (Ennominae), Pyrrhorachis pyrrhogona C (Geometrinae) and Noreia achloraria C (Desmobathrinae) were represented by.25, 24,23 and 21 individuals respectively. 12.7% of the total species collected (seven species) were considered as rare species. They were Agathia cristifera o (Geometrinae), Agathia laetata o (Geometrinae), Comibaena biplaga o (Geometrinae), Comostola cedilla (Geometrinae), Dindica olivacea C (Geometrinae), Ornithospila avicularia € (Geometrinae) and Eumelea rosalia o (Oenochrominae). As many as 22 species collected were represented by single individuals (singletons), comprising of 40.0% of total species collected. These singletons were highly represented in Ennominae and Geometrinae with 40.9% each