Rediscovery of an Endemic Subspecies, Euphorbia watanabei subsp. watanabei (Euphorbiaceae), in Izu Peninsula, Shizuoka Prefecture, Japan

Abstract

We rediscovered a population of Euphorbia watanabei Makino subsp. watanabei (Euphorbiaceae) from Izu peninsula, Shizuoka Pref., Japan. This subspecies is endemic to the prefecture, and there has been no report since the 1960's in the Izu peninsula. The new population consisted of about 100 individuals in a semi-natural grassland dominated by Pteridium aquilinum subsp. japonicum.