Biosystematic Studies on the Genus Hemerocallis (Liliaceae) : II. Variation in Gross Morphology of the H. fulva Complex with Special Reference to the Identity of H. fulva v. longituba and v. disticha

Abstract

Hemerocallis fulva sensu lato is known to be an exceedingly polymorphic species. In a recent taxonomic revision of the genus Hemerocallis in Japan and its neighbouring regions, Matsuoka and Hotta (1966) distinguished primarily by gross morphology, the following seven infraspecific taxa in the H. fulva complex: H. fulva L. v. fulva : v. Kwanso Regel ; v. sempervirP-ns (Araki) H. Hotta : v. littorea (Makino) M. Hotta ; v. longituba (Miq.) Maxim. ; v. disticha (Donn) M. Hotta ; and v. paucijlora M. Hotta & Matsuoka. However, there are still considerable discre· pancies in the taxonomic concept and treatment of this complex group. It has not been resolved, for example, whether or not several native Japanese taxa now referred to the H. fulva complex, such as v. disticha, v. longituba, etc. in the sense of Matsuoka and Hotta (1. c. ) should be referred to the same taxonomic group as the continental taxon, H. fulva v. fulva. This latter group also includes the double-flowered taxon, v. Kwanso which is widely distributed over the Japanese Islands excepting northern Hokkaido (cf. Ohwi, 1953, 1965; Kitamura et al., 1967).This paper particularly attempts to draw attention to the taxonomical identity of two native Japanese taxa, H. fulva v. longituba and v. disticha. In the present study; the variabilities of the plants, referred to the following four taxa of this complex, i. e., v. fulva, v. Kwanso, v. disticha, and v. longituba, are analyzed and compared, and their taxonomic status briefly discussed