Molecular and morphological evidence reveals a new lepidopteran genus, Micrometasia (Crambidae, Spilomelinae, Steniini), with implications for insular speciation of endemic moths in Japan

Researchers have uncovered a new genus of moth, Micrometasia, endemic to Japan, shedding light on the evolutionary and biogeographic patterns of insular speciation. This discovery, based on molecular and morphological evidence, includes two previously undescribed species: M. ryukyuensis from the Ryukyu Islands and M. melanatella from the Ogasawara Islands, along with a redescription of the female of M. bilineatella. Phylogenetic analysis using mitochondrial and nuclear genes places Micrometasia within the detritivorous tribe Steniini, hinting at potential undescribed diversity and multiple colonization routes into Japan's archipelago. The study also highlights small-scale radiation and morphological divergence on oceanic islands, offering new insights into the biodiversity of Japanese moths.

Matsui, Y., Park, J., Yagi, S., Kimura, M., & Hirowatari, T. (2025). Molecular and morphological evidence reveals a new lepidopteran genus, Micrometasia (Crambidae, Spilomelinae, Steniini), with implications for insular speciation of endemic moths in Japan. Invertebrate Systematics, 39(10). https://doi.org/10.1071/is25049