Description and life history of a new genus and species of Limacodidae (Lepidoptera, Zygaenoidea) from Taiwan, the first with a monkey-slug-like caterpillar from outside the New World

The genus <i>Yufengus</i> <b>gen. nov.</b> is established for a new species of Limacodidae, <i>Y. atrophaneuroides</i> <b>sp. nov.</b> <i>Yufengus</i> is from Taiwan, yet its larva is similar to monkey-slug caterpillars in the New World (<i>Phobetron</i> Hübner, 1825: Limacodidae) in being covered with hairy, detachable tubercles. Monkey-slug caterpillars are currently known to form a monophyletic group which include as many as eight genera in the Americas referred to as the <i>Phobetron</i> complex by Epstein (1996). Although the larva of <i>Yufengus</i> appears, in particular, most similar to the genus <i>Phobetron</i>, a closer look at morphology reveals fundamental differences that are shared with Asian <i>Phrixolepia</i> Butler, 1877. Caterpillars of the new genus are structurally similar to <i>Phrixolepia</i>, but <i>Phrixolepia</i> is more translucent, less hairy, and differs in other characters including those of adults, separated by wing pattern and genitalia. In addition to describing the new genus <i>Yufengus</i>, we explore whether it is indeed in the same clade as the <i>Phobetron</i> complex of genera from the New World. The life history and morphology of adults and immature stages are described in this study.