Weissia kiiensis (S.Okamura) Y.Inoue & H.Tsubota, 2017

Inoue, Yuya & Tsubota, Hiromi, 2017, A taxonomic revision of cleistocarpous species of Weissia (Pottiaceae, Bryophyta) in Japan, Phytotaxa 306 (1), pp. 1-20 : 12-14

3. Weissia kiiensis (S.Okamura) Y.Inoue & H.Tsubota , comb. nov.

Basionym:— Astomum kiiense S.Okamura, Bot. Mag. (Tokyo) 25: 140. 1911 ( Okamura 1911). Type:— JAPAN. Wakayama Pref.: Wakanoura, the foot of Mt. Goboyama, 9 December 1900, K. Minakata s.n. (holotype, NICH-M 37518!).

Description:—( Figs. 2 D , & 4A–I ). Plants when moist ca. 2–10 mm high including capsules. Stems simple or branched, erect; central strand present; sclerodermis weakly differentiated; hyalodermis undifferentiated. Leaves strongly crisped when dry, spreading when moist, gradually becoming larger toward shoot apex. Autoicous. Perichaetial leaves much larger than vegetative leaves, lanceolate to linear lanceolate, (1.7–)2.3–3.1(–3.6) mm long and (0.45–)0.5–0.7(–0.8) mm wide at base, tapering to an acuminate apex from a broad oblong base; margins incurved in distal 1/2–2/3, plane in basal portion, smooth or nearly smooth with faint projections at shoulder part of leaf base; costa stout, excurrent in a point reaching (40–)70–115(–160) μm, papillose on adaxial surface and smooth on abaxial surface; guide cells 4 in a single row at midleaf; adaxial and abaxial stereids 2–3 stratose at midleaf; upper laminal cells subquadrate, 6–10 × 6–10 μm, papillose on both surfaces with bifid papillae; basal laminal cells enlarged, rectangular, 50–120 × 8–14 μm, smooth. Perigonial leaves much smaller than vegetative leaves, oval, acuminate, concave. Asexual reproduction unknown. Setae (70–)130–240(–350) μm long; epidermal cells quadrate to subquadrate, thin walled. Capsules cleistocarpous, deeply immersed among perichaetial leaves; urn spherical, (490–)645–770(–840) × (460–)580–700 (–800) μm, with a slightly oblique finger-like apiculus reaching (110–)150–205(–230) μm long; exothecial cells irregularly quadrate, smooth; stomata phaneroporous, (3–)4–6(–9) at base of capsule; annulus absent. Operculum undifferentiated. Calyptra cucullate, (510–)575–680(–775) μm long. Spores (16.25–)20–24(–30) μm in diam., densely papillose.

Taxonomic notes:— Saito (1975) synonymized A. kiiense with W. longifolia Mitt. [as W. crispa (Hedw.) Mitt. ]. However, in their taxonomic revision of European Weissia subg. Astomum, Crundwell & Nyholm (1972) suggested that Japanese plants that had been named W. crispa belonged to a non-European species.After examination of the holotypes of A. kiiense (NICH-M 37518) and W. longifolia (NY 1408141), we conclude that A. kiiense should be resurrected and transferred to Weissia . W. kiiensis has a similar appearance to W. longifolia in having the deeply immersed capsules without an annulus, but the capsule shape of the former is spherical while that of the latter is ellipsoidal. W. kiiensis is also quite similar to the North American species W. muhlenbergiana ( Swartz 1829: 74) Reese & Lemmon (1965: 282) as suggested by Andrews (1922). Crum & Anderson (1981) shared Crundwell’s opinion (in litt.) that Japanese plants referred to A. crispum were identical with the North American species W. muhlenbergiana [as A. muhlenbergianum (Sw.) Grout (1938: 152) ]. In the present study we examined some specimens identified as W. muhlenbergiana (Appendix 2) and confirmed two morphological groups: (1) capsules without an annulus and (2) capsules with an annulus. No distinct morphological differences are apparent between W. kiiensis and the former group identified as W. muhlenbergiana . In the plotologue of Phascum muhlenbergianum Swartz (1829) did not refer to whether the capsules have or lack an annulus. We have not been able to locate the type specimen of P. muhlenbergianum . Until additional morpho-molecular data are obtained to clarify the taxonomic identities of Japanese and North American plants, we consider these species best regarded as distinct.

Distribution:— Japan (Hokkaido, Honshu, Shikoku and Kyushu)

Representative specimens examined:— JAPAN. Hokkaido, Hokkaido Pref.: Obihiro City, Midorigaoka Park , ca. 50 m elev., 42°54′17″N, 143°11′17″E, 12 September 2012, Y. Inoue 1493 (HIRO, DNA voucher) ; Honshu, Fukushima Pref.: Fukushima City, Mt. Shinobu , ca. 95 m elev., 37°46′18″N, 140°28′42″E, 9 March 2015, Y. Inoue 3169 (HIRO, DNA voucher) ; Tokyo Pref.: Nishitokyo City, The University of Tokyo Tanashi Forest , ca. 90 m elev., 35°44′05″N, 139°32′28″E, 10 March 2015, Y. Inoue 3183 (HIRO, DNA voucher) ; Niigata Pref.: Tsubame City, Shincho , ca. 10 m elev., 37°38′07″N, 138°49′48″E, 26 October 2015, T. Sato 1430 (HIRO, DNA voucher) ; Shizuoka Pref.: Kakegawa City, Nagaya , ca. 55 m elev., 34°45′30″N, 137°59′40″E, 19 December 2015, Y. Inoue 3816 (HIRO, DNA voucher) ; Aichi Pref.: Shinshiro City, Yanai , ca. 30 m elev., 34°51′52″N, 137°27′34″E, 18 March 2013, Y. Inoue 1816 (HIRO, DNA voucher) ; Nara Pref.: Ikoma District, Ikaruga-cho, Horyuji Temple , ca. 60 m elev., 5 March 2010, K. Une 10243 (TNS 211531) ; Wakayama Pref.: Wakanoura, the foot of Mt. Goboyama , 9 December 1900, K. Minakata s.n. (holotype of Astomum kiiense , NICH-M 37518) ; Hiroshima Pref.: Kure City, Kamikamagarijima Isl. , ca. 25 m elev., 34°11′23″N, 132°43′09″E, 20 December 2015, Y. Inoue 3826 (HIRO, DNA voucher) ; Shikoku, Kochi Pref.: Kochi City, Mononobecho , Odachi , ca. 200 m elev., 33°41′52″N, 133°52′25″E, 8 March 2014, Y. Inoue 2606 (HIRO, DNA voucher) ; Kyushu, Oita Pref.: Tsukumi City, Chinu , ca. 20 m elev., 33°04′29″N, 132°52′53″E, 2 March 2013, Y. Inoue 1788b (HIRO, DNA voucher) ; Miyazaki Pref.: Nichinan City, Hoshikura , ca. 20 m elev., 31°37′29″N, 131°21′33″E, 28 November 2015, Y. Inoue 3813 (HIRO, DNA voucher) .

Figures

FIGURE 2. Scanning electron microscope (SEM) images of cleistocarpous capsules of Weissia in Japan and of Trachycarpidium lonchophyllum. A, W. exserta (Y. Inoue 3828 in HIRO); B, W. japonica (Y. Inoue 3830 in HIRO); C, W. parajaponica (T. Yamaguchi 36925 in HIRO); D, W. kiiensis (Y. Inoue 3813 in HIRO); E, T. lonchophyllum (O. Yano & B.L. Morretes 28820 in SP). 1, Capsule overviews; 2, Close up of upper portion of capsules (Arrowheads indicate dehiscence line).

FIGURE 4. Weissia kiiensis (A–I) and W. prajaponica (J–W).A, Habit (dry); B, Cross section of stem; C, Perichaetial leaf; D, Vegetative leaf; E & F, Cross sections of perichaetial leaf; G, Sporophyte; H, Cross section of seta; I, Calyptra; J, Habit (dry); K, Cross section of stem; L–N, Perichaetial leaves; O–R, Vegetative leaves; S & T, Cross sections of perichaetial leaf; U, Sporophyte; V, Cross section of seta; W, Calyptra. A–I drawn from K. Minakata s.n. (NICH-M 37518, holotype of Astomum kiiense); J, V from T. Yamaguchi 36925 (HIRO, paratype); K, L, O, P, S, T, W from Y. Inoue 3864 (HIRO, holotype); M, Q from Y. Inoue 3925 (HIRO, paratype); N, R from T. Yamaguchi 30497 (HIRO, paratype); U from T. Yamaguchi 18666 (HIRO, paratype).