Taxonomy
Valid name: Bactrocera (Tetradacus) minax (Enderlein, 1920)
Preferred common name: Chinese citrus fly.
Synonyms:
Polistomimetes minax (original combination in Enderlein, 1920)
Callantra minax (subsequent combination in Hardy & Adachi, 1954)
Dacus minax (subsequent combination in Hardy, 1977)
Mellesis citri Chen, 1940 (junior synonym)
Tetradacus citri (subsequent combination in Chen & Zia, 1955)
Tetradacus tsuneonis citri (subsequent combination in Zia & Chen, 1954)
Valid name: Bactrocera (Tetradacus) tsuneonis (Miyake, 1919)
Preferred common name: Japanese orange fly.
Synonyms:
Dacus tsuneonis (original combination in Miyake, 1919)
Tetradacus tsuneonis (subsequent combination in Bezzi, 1919)
Dacus cheni Chao, 1987 (junior synonym)
Bactrocera minax and B. tsuneonis are part of Bactrocera subgenus Tetradacus, which holds ten species in total (Hancock and Drew 2019Hancock and Drew 2019:
Hancock DL, Drew RAI, 2019. Further notes on subgenus Tetradacus Miyake of Bactrocera Macquart (Diptera: Tephritidae: Dacinae), with a revised key to species. Australian Entomologist 46: 43–46.).
Morphology-based identification
Bactrocera minax and
B. tsuneonis are strikingly larger than most
Bactrocera and are more 'wasp-like' with an elongated abdomen. They can be recognized reliably using morphological characters. Member of subgenus
Tetradacus are remarkable in that they have a yellow medial vitta on the scutum, which is not seen in other
Bactrocera subgenera—but is common in
Zeugodacus and
Dacus.
Molecular identification
COI sequence data can be used to identify both
Bactrocera minax and
B. tsuneonis (
Doorenweerd et al. 2024Doorenweerd et al. 2024:
Doorenweerd C, San Jose M, Leblanc L, Barr N, Geib SM, Chung AYC, Dupuis JR, Ekayanti A, Fiegalan E, Hemachandra KS, Hossain MA, Huang C, Hsu Y, Morris KY, Maryani A. Mustapeng A, Niogret J, Pham TH, Thi Nguyen N, Sirisena UGAI, Todd T, Rubinoff D, 2024. Towards a better future for DNA barcoding: Evaluating monophyly‐ and distance‐based species identification using COI gene fragments of Dacini fruit flies. Molecular Ecology Resources 24: e13987. https://doi.org/10.1111/1755-0998.13987).
Distribution
Bactrocera minax is widespread in mainland Southeast Asia where it has adapted to a temperate climate with mild winters, in Bhutan, Nepal, China, and eastern India.
Bactrocera tsuneonis is known from Kyushu and the Ryukyu islands of Japan, and southeastern provinces of China. The native ranges of both species remain unclear but were likely only part of their current distributions.
Further information
Bactrocera minax is the most destructive pest of citrus in China (
Xia et al. 2018Xia et al. 2018:
Xia Y, Ma X, Hou B, Ouyang G, 2018. A Review of Bactrocera minax (Diptera: Tephritidae) in China for the Purpose of Safeguarding. Advances in Entomology 06: 35–61. https://doi.org/10.4236/ae.2018.62005). Both
B. minax and
B. tsuneonis are listed as "category B" pests in
Vargas et al. (2015)Vargas et al. (2015):
Vargas RI, Pinero JC, Leblanc L, 2015. An overview of pest species of Bactrocera fruit flies (Diptera: Tephritidae) and the integration of biopesticides with other biological approaches for their management with a focus on the pacific region. Insects 6: 297–318. https://doi.org/10.3390/insects6020297. A category B pest is there defined as "polyphagous fruit pests or destructive specialists more restricted in distribution, but at elevated risk of spreading to new locations". These species are especially threatening because they are not attracted to any of the known lures used in surveillance trapping and invasions.
