First record of Clavelina lepadiformis (Clavelinidae: Aplousobrachia), an invasive Atlantic form, from Wakayama Prefecture, Japan

Abstract

The colonial ascidian Clavelina lepadiformis (Müller, 1776), commonly known as the light bulb tunicate, is of concern as an invasive species due to its extensive distribution from its original habitat in the northeast Atlantic. This study reports the first discovery of C. lepadiformis in Kushimoto, Wakayama Prefecture, Japan. Molecular phylogenetic analysis using the mitochondrial cytochrome oxidase c subunit I (COI) gene sequences indicated that C. lepadiformis from Kushimoto sample belonged to the Atlantic clade. The present study improves our understanding of the geographic distribution of this species in Japan, adds to our knowledge of its invasion dynamics within the country, and suggests the potential for ongoing environmental impacts. Continuous monitoring is needed to further elucidate the dispersal mechanisms and ecological impacts of this invasive species.