A systematic review of the East Asian Vidalia Robineau-Desvoidy (Diptera: Tephritidae: Trypetini: Trypetina), with recognition of a new species

The East Asian species of the horn-headed tephritid genus Vidalia are systematically reviewed, including V. armifrons (Portschinsky, 1892), V. itoi Han and Ro, sp. nov., and V. satae Ito, 1984. A key, diagnoses, descriptions, photographs of morphological structures (including genitalia), and a 16S rDNA phylogram of 18 genera and 26 species within the tribe Trypetini are provided. The species status of V. armifrons has previously been unclear. However, we were able to distinguish the light-colored V. itoi, sp. nov., from the dark-colored V. armifrons based on the specimens collected from northern South Korea. In addition to differences in coloration, the female aculei exhibit significant interspecific variation. Nevertheless, the two species are indistinguishable based on 16S rDNA sequences, supporting their status as sister species. The dark-colored V. armifrons appears to be distributed in more northern regions (East Siberia, northern China, and Korea), whereas V. itoi has a more southern distribution, extending as far as Japan. Both species coexist in Korea and presumably also in China and Russia, but only V. itoi is found in Japan. Minor differences in flight periods may exist between the two species, likely due to their use of different host plants in northern South Korea. Based on expanded sampling of V. satae, this species is hereby resurrected from synonymy with V. accola (Hardy, 1973) due to significant differences in wing pattern. Furthermore, our 16S rDNA phylogram supports a previously proposed morphological phylogenetic hypothesis: multiple independent, convergent evolutions of male head ornamentation have occurred within the tribe Trypetini, likely driven by intense selection pressure arising from aggressive male butting behavior.