Onespa gala (Godman, 1900)

Zhang, Jing, Cong, Qian, Shen, Jinhui, Song, Leina & Grishin, Nick V., 2025, Advancing butterfly systematics through genomic analysis, The Taxonomic Report of the International Lepidoptera Survey 12 (5), pp. 1-201 : 159

Onespa gala (Godman, 1900) and Onespa brockorum Austin & A. Warren, 2009 lack overall genetic differentiation typical of species-level taxa

Genomic analysis of Onespa Steinhauser, 1974 (type species Onespa nubis Steinhauser, 1974 ) reveals a surprise ( Fig. 123 ). Despite phenotypic differences in both sexes, including slight differences in genitalia between Onespa brockorum Austin & A. Warren, 2009 (type locality in Mexico: Sonora) and Onespa gala (Godman, 1900) (type locality in Mexico: Veracruz, holotype sequenced as NVG-18117F05) discussed by Austin and Warren (2009) (who nevertheless note “ Onespa brockorum is very similar to O. gala ”), we failed to find DNA differences between them typical of species-level taxa. The two species do not separate phylogenetically, i.e., they do not form prominent and strongly supported clades in any of the three trees: the nuclear genome (autosomes), the Z chromosome, and the mitochondrial genome. This is the first example we encountered when a pair of species with reported genitalic differences in both sexes (albeit rather minute in our opinion) do not form separate well-supported clades in the genomic trees, and it warrants a more detailed study. It is possible that the two taxa are subspecies (in genome-scale trees, valid subspecies do not always segregate into discrete clades), or they speciated only recently and have not gained sufficient overall genetic differentiation in the presence of reproductive isolation. Here, we bring this unusual example to the attention of the research community without proposing taxonomic changes to the current classification.

Figures

Fig. 123. Phylogenetic trees of Onespa species inferred from protein-coding regions in: a) the nuclear genome (autosomes), b) the Z chromosome, and c) the mitochondrial genome. Different species are shown in different colors: O. nuba sp. n. (red), O. nubis (blue), O. nakamura Austin & A. Warren, 2009 (black), O. brockorum (purple), and O. gala (green).