A generic classification of Davalliaceae is proposed to recognize five genera and two sections for monophyletic groups detected by molecular phylogenetic studies. The delimitation of the taxa, except for Humata, differs remarkably from the ones adopted in previous classifications. Davallia is divided into sections Davallia and Trogostolon (stat. nov.), of which the former includes Scyphularia and the latter includes Davallia trichomanoides and close relatives. Humata contains Davallia corniculata. The new genus Araiostegiella comprises A. perdurans and two related species, which have long been assigned to Araiostegia. The revived genus Wibelia is composed of W. denticulata (type) and related species. Davallodes is a polymorphic genus that accommodates Paradavallodes, Araiostegia hymenophylloides and its close relatives, as well as Davallodes s.s. A key to the genera and sections and a set of their diagnostic characters are given and new combinations for the species are presented. The exclusion of Gymnogrammitis and Leucostegia from the family is also discussed.
The taxonomy of Polygonatum in Japan is revised. Nine species, four nothospecies, including P. ×desoulavyi (= P. desoulavyi var. yezoense = P. miserum), P. ×domonense and P. ×azegamii (= P. desoulavyi var. azegamii), and six varieties are recognized. Desoulavy 142 is superseded by Desoulavy 143 (both in LE) as a lectotype of P. ×desoulavyi. It is presumed that P. ×desoulavyi, P. ×domonense and P. ×azegamii are hybrid derivatives between P. humile and P. involucratum, between P. involucratum and P. lasianthum, and between P. falcatum and P. involucratum, respectively. Polygonatum amabile is considered to be a species distinct from P. lasianthum, as in Yatabe's original species concept. Polygonatum trichosanthum is reduced to var. trichosanthum under P. falcatum. A key to the species, nothospecies and varieties is provided.
Two new varieties, Hosta kikutii F. Maek. var. densinervia N. Fujita & M. N. Tamura and H. kikutii var. scabrinervia N. Fujita & M. N. Tamura are described. Hosta kikutii var. densinervia differs from H. kikutii var. kikutii in having the nerves of the leaves more or less close together and papillose abaxially. Hosta kikutii var. scabrinervia differs from H. kikutii var. densinervia in having the nerves on the abaxial surface of the leaves prominently papillose. Plants belonging to these two varieties were formerly assigned to H. kikutii var. polyneuron (F. Maek.) N. Fujita (= H. polyneuron F. Maek.), which is now regarded as a doubtful taxon. A change in status, H, tsushimensis N. Fujita var. tibae (F. Maek. ex H. Hara) N. Fujita & M. N. Tamura, is also proposed, A key to the varieties of H. kikutii and a key to the varieties of H. tsushimensis are provided.
Based on morphology and chromosome numbers, Arisaema inaense (Seriz.) K. Sasamura et J. Murata is newly recognized at the rank of species and a new species A. nagiense T. Kobayashi, K. Sasamura et J. Murata is described. Both are diploid with 2n=26 and lack the accessory buds that always accompany the axillary buds of tetraploid plants of A. ovale Nakai. In the A. ovale group, A. nagiense is unique in the inflorescence unfolding before the leaf blade.
Arisaema maekawae J. Murata & S. Kakishima, a new species of the Arisaema serratum group (Araceae), is described from Japan. This species is most similar to A. angustatum but distinct in the ventrally whitish and somewhat verrucose spathe blade and in the thick cylindrical spadix appendage.
Carex ruralis J. Oda & Nagam. and C. koyaensis J. Oda & Nagam. (sect. Capitellatae) are described from Japan as new to science. These species are similar to C. capillacea Boott, but C. ruralis is distinct from C. capillacea in having fewer (4-8) pistillate flowers, leaves narrower (0.5-0.8 mm wide) and involute to trigonous, and perigynia lacking glandular dots. Carex koyaensis is distinct from C. capillacea in having rhizomes long creeping, culms shorter (10-20 cm long), leaves recurved, and perigynia weakly nerved and without glandular dots. Both species are also distinct from C. capillacea in the achene micromorphology. The cellulose anticlinal walls of C. capillacea are exserted beyond the silica deposits, while those of C. ruralis and C. koyaensis are entirely covered by the silica deposits. The satellite bodies of Carex ruralis and C. koyaensis are smaller and fewer than those of C. capillacea. Moreover C. koyaensis often has a honeycombed anticlinal wall. A key to the Japanese species of Carex sect. Capitellatae is provided.
Carex kagoshimensis Tak. Shimizu is described as new to science. It is similar to C. laticeps in the shape of the achenes, but differs by having emarginate scales in the staminate inflorescence, plants (except utricle) glabrous, wider leaves (2 to 3 times wider), and utricles ascending and sparsely pubescent. It faintly resembles C. insaniae var. papillaticulmis in the shape of the utricles, but differs by having deep notches on the ridges of the achenes and a strongly curved beak lacking an annular appendage, the emarginate scales of the staminate flowers, numerous utricles (at least 3 times as many) on the lowest spike and smooth bract sheaths. Carex kagoshimensis occurs in Yamaguchi, Miyazaki and Kagoshima prefectures.
A new species, Liparis purpureovittata (Orchidaceae), is described from central and northern Japan on the basis of both morphological and molecular characters. This species is distinguishable from the closely related Liparis kumokiri in the abruptly dilated labellum (vs. the gradually dilated labellum in L. kumokiri), the labellum recurved strongly in the middle (vs. the labellum strongly recurved in both the middle and distal part), and the column with rounded marginal wings (vs. angular marginal column wings).