Dryopteris caudipinna (Dryopteridaceae) new to Hiroshima Prefecture, Japan

Abstract

Dryopteris caudipinna Nakai was newly recorded from Hiroshima Prefecture, Japan. Though this rather rare diploid sexual fern has previously been known from Japan and South Korea, most factors determining its distribution remain unclear. Population of D. caudipinna was restricted to the southern part of Ujina Island, where rather wet humus rich evergreen forest floors were observed. The number of individuals was estimated to be approximately 500 or higher. This report also describes new record of this fern from a Seto Inland Sea region.