Title: An evaluation of the species status of Bactrocera invadens and the Bactrocera dorsalis (Diptera: Tephritidae) complex Authors
|San Jose, Michael -|
|Leblanc, Luc -|
|Rubinoff, Dan -|
Submitted to: Annals of the Entomological Society of America
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 24, 2013
Publication Date: N/A
Interpretive Summary: The fruit fly genus Bactrocera (Tephritidae) contains over 500 species which are native to tropical and sub-tropical areas. Many species in this genus are pests, attacking a wide variety of fruits and vegetables, making them one of the worst tropical pest insects in the world. Through agricultural trade, many species have been spread throughout the world. Many of the species that have been spread are members of a single species complex (the Bactrocera dorsalis complex). Unfortunately, we are not clear on the relationship between the members of this species complex, whether they are distinct species or should be considered populations of a single species. The goal of this project was to use molecular techniques to sequence and analyze taxonomically informative genes from a collection of flies from within this complex. Our results indicate that the Bactrocera dorsalis complex appears to represent single species rather than a collection of many closely related species. In addition, the species recently described as Bactrocera invadens is actually genetically indistinguishable from B. dorsalis, and should be considered this species.
Technical Abstract: The genus Bactrocera (Tephritidae) contains over 500 species, including many severe pests of fruits and vegetables. While native to tropical and sub-tropical areas of Africa, India, Southeast Asia and Australasia, a number of the pest species, largely members of the Bactrocera dorsalis complex, have become widespread through agricultural trade. The B. dorsalis complex includes several morphologically and ecologically similar pest species, making species designations uncertain. One of these, B. invadens, endemic to Sri Lanka, has spread across Africa in the last decade and has become a major agricultural pest. We sequenced one mitochondrial and two nuclear genes from 79 specimens belonging to 22 species to construct phylogenies and examine species relationships and limits within the genus Bactrocera and several species of the B. dorsalis complex -- specifically addressing the placement of B. invadens. Results indicate the B. dorsalis complex is polyphyletic. Bactrocera invadens and several other species within the B. dorsalis complex (B. dorsalis, B. papayae and B. philippinensis) are also paraphyletic with respect to each other and probably represent a single genetically indistinguishable, phenotypically plastic pest species that has spread throughout the world.