In January, she will compare the Russian population’s DNA to that of other populations and other species to confirm her suspicions. “Based on geography, based on behavior, and based on a phenotypic variation we saw in the wing pattern, we can speculate that this represents something different, something new,” Zaspel said.
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Only male moths exhibit blood feeding, she noted, raising the possibility that as in some species of butterflies and other moths, the Russian moths do it to pass on salt to females during copulation.

“There is no evidence it prolongs the life of the male, or anything like that,” she said. “So we suspect that it is probably going to the female.” The sexual gift, she said, would provide a nutritional boost to young larvae that feed on leaf-rich, but sodium-poor, diets.