J. Jpn. Bot. 90: 92–97 (2015) Systematic Studies of Parasenecio (Asteraceae-Senecioneae) I. Parasenecio katoanus, a New Species from Yamagata Prefecture, Northern Honshu, Japan Yuichi KADOTA Department of Botany, National Museum of Nature and Science, 4–1–1, Amakubo, Tsukuba, 305-0005 JAPAN E-mail:
[email protected] (Accepted on November 1, 2014) A new species of Parasenecio (Asteraceae-Senecioneae), P. katoanus Kadota, is described from the Shônai region, Yamagata Pref., northern Honshu, Japan. Parasenecio katoanus is distinguished from P. nikomontanus (Matsum.) H. Koyama by having 1) triangular-pentagonal, somewhat fleshy, dimly lustrous, usually glabrous leaf blades, 2) longer involucres with acute involucral phyllaries, 3) longer achenes, and 4) ascending peduncles at an acute angle. It was found that the flowers were fragrant in the midst of flowering time. Parasenecio katoanus is hitherto known only from the Shônai area of Yamagata Pref. Key words: Asteraceae, Japan, new species, Parasenecio katoanus, the Shônai region, Yamagata Prefecture. This is the first part of a series of systematic blades and is commonly distributed on the studies of the genus Parasenecio (Asteraceae- Japan Sea side of Honshu Island ranging from Senecioneae). The genus consists of more Akita Pref. to Shimane Pref. (Koyama 1995, than 60 species (Chen 1999). It shows an East Kadota unpubl.). The Japanese vernacular name Asian and Eastern North American disjunct ‘Ô-kani-kômori’ is derived from the shape of distribution pattern and its considerable number leaf blades, of which ‘Kani’ means the shape of of species are recognized in the Sino-Japanese crab carapace. floristic region (Koyama 1983, Chen 1999, Parasenecio nikomontanus also occurs Kadota 2009).