Submitted to: Biological Journal of the Linnean Society, London
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/13/2007
Publication Date: 4/1/2008
Citation: Scheffer, S.J., Condon, M., Bann, D., Flaherty, K., Gammons, J., Johnson, J., Marsteller, S., Lewis, M.L., Adams, D.C. 2008. Uncovering tropical diversity: six sympatric cryptic species of Blepharoneura (Diptera: Tephritidae) in flowers of Gurania spinulosa (Cucurbitaceae) in eastern Ecuador. Biological Journal of the Linnean Society, London. 93:779-797. Interpretive Summary: Plant-feeding flies are often important pests of agricultural crops and routinely cause millions of dollars in losses. This paper investigates the biology of a number of previously unknown fly species that feed in the flowers and fruits of plants in the squash family. It uses DNA molecular data to show that even in a single location, many fly species may be present attacking the same host plant. It is hypothesized that differences in courtship behaviors functions to keep the fly species distinct. This information will be of interest to scientists and pest managers.
Technical Abstract: Diversification of phytophagous insects is often associated with changes in the use of host taxa and host parts. We focus on a group of newly discovered neotropical tephritids in the genus Blepharoneura, and report the discovery of an extraordinary number of sympatric, morphologically cryptic species all feeding as larvae on flowers of a single host species at a single field site in eastern Ecuador. The host plant, Gurania spinulosa, is functionally dioecious and highly sexually dimorphic. Molecular analyses of the mitochondrial cytochrome oxidase I gene from flies reared from flowers of G. spinulosa reveal six distinct haplotype groups that differ by 7.2-10.1% (uncorrected pairwise distances). Haplotype groups correspond to six distinct and well-supported clades. Flies in all six clades feed as larvae on calyx tissue, but members of five clades specialize on the calyces of flowers of a particular sex: three clades comprise male flowers specialists; two clades comprise female flower specialists; the sixth clade comprises generalists reared from male and female flowers. The six clades occupy significantly different morphological spaces defined by wing pigmentation patterns; however, diagnostic morphological characters were not discovered. Behavioral observations suggest specific courtship behaviors may play a role in maintaining reproductive isolation among sympatric species.