title: Morphological comparison among Drosophila lini and its two new sibling species (Diptera: Drosophilidae).
abstract: Morphological differences are investigated using several culture strains of three sibling species collected from Taiwan and Guangdong in China and Pyinoolwin and Yangon in Myanmar. Careful examination of male terminalia reveals distinguishable differences in the paramere and the aedeagal basal process among the three species. In addition, a number of quantitative characters are compared. Kruskal-Wallis tests with Bonferroni correction, which are carried out separately for each sex, detect significant differences in 15 characters, of which two are male-specific, among the three species. Canonical discriminant analysis using these characters reveals that the three species can be distinguished from each other with high confidence for both sexes. The results clearly show the presence of three good species, Drosophila (Sophophora) lini Bock & Wheeler, 1972 and its two new siblings. The new species are described as Drosophila (Sophophora) ohnishii sp. nov. from Pyinoolwin and Drosophila (Sophophora) ogumai sp. nov. from Yangon. The morphological differentiation among the three sibling species does not coincide with the degree of reproductive isolation (based on a previous study). The premating isolation pattern suggests two possibilities that premating isolation has been evolved or reinforced in sympatric populations between D. ohnishii and D. lini and between D. ohnishii and D. ogumai or that it has evolved in a very restricted local population of D. ohnishii, possibly by a few mutations.
authors.affiliation: Institute of Low Temperature Science, Hokkaido University, Sapporo, Japan.
authors.forename: Mst Thangima
authors.initials: MT
authors.lastname: Zannat
authors.forename: Masanori J
authors.initials: MJ
authors.lastname: Toda
mesh_terms: D000818:Animals; D005075:Biological Evolution; D002681:China; D004330:Drosophila / Q000033:anatomy & histology* / Q000145:classification*; D005260:Female; D008297:Male; D002052:Myanmar; D010802:Phylogeny; D012726:Sexual Behavior, Animal; D013045:Species Specificity