Distribution of long-horn beetles (Cerambycidae: Coleoptera) within the Fijian archipelago

Abstract

Long-horn beetles (Family: Cerambycidae) in Fiji consist of 124 described species within 45 genera, of which 110 (88.7%) species are considered endemic. Despite their conservation value, ecological significance and cultural importance, little scientific research has been conducted on the taxonomy or ecology of Cerambycidae in Fiji. This biogeographical study surveyed Cerambycidae by Malaise trapping on ten Fijian Islands. A total of 438 individuals and 44 species of Cerambycidae were recorded. Thirty three of the species collected are endemic to Fiji; three other species are native and eight species are new records for Fiji and/or new species. Twenty seven species were recorded from only one island and 20 species were recorded only as singletons. There was an expected significant relationship between the number of species collected on an island and the number of sampling events. The highest number of species, 23, was recorded on the largest island, Viti Levu, followed by Gau with 13 species and Vanua Levu and Kadavu with 12 species each. There was a positive relationship between species richness and island size but this was lost if the effect of sample number was taken into account. The results indicate that the species-area relationship may hold for Fijian Cerambycidae, but additional collecting events, over more of the annual cycle, and involving multiple collecting methods may be required to fully catalogue the current Fijian fauna.