Size and shape variability of the wing in burnet moth, Zygaena ephialtes (L., 1767) (Lepidoptera: Zygaenidae)

The burnet moth, Zygaena ephialtes (L., 1767) (Lepidoptera: Zygaenidae) is a distinctly polymorphic species of moth appearing in several color morphotypes. This study examined whether the variability of the Z. ephialtes forewing could be explained by geometric morphometric methods. The analysis included 70 male specimens from five localities in Montenegro (Plu??ine, Tepca, Dobrilovina, Gusinje and Rugovska Gorge), and one locality in North Macedonia (Ko??uf Mountain) belonging to the subspecies Zygaena ephialtes pannonica Holik, 1937 and Zygaena ephialtes istoki Silbernagel, 1944, respectively, collected between 1981 to 2018. The forewing outline and the aposematic color pattern formed by five spots were analyzed separately. Neither forewing size nor forewing spots pattern size exhibited interpopulation heterogeneity. Size variation of the basal spot was independent from the rest. Considering the forewing outline shape, the apical portion was the most variable and different among populations. Two morphological groups were recognized: a group with a narrower pointed forewing (samples: Ko??uf Mountain, Rugovska Gorge and Tepca), and a group with a wider forewing with a blunt apex (Plu??ine, Gusinje). Neither the outline or the spots pattern of the forewing supported the distinction between the subspecies Z. e. pannonica and Z. e. istoki.