Boehmeria macrostachya var. minuticymosa, 2013
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publication ID |
https://doi.org/10.3767/000651913X674116 |
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persistent identifier |
https://treatment.plazi.org/id/03D987B7-FF95-514A-FD73-5D11DBCFF7AC |
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treatment provided by |
Felipe |
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scientific name |
Boehmeria macrostachya var. minuticymosa |
| status |
var. nov. |
k. var. minuticymosa Acharya, Friis & Wilmot-Dear , var. nov. — Fig. 27 View Fig ; Map 28 View Map 28
Ab omnibus ceteris varietatibus var. canescenti excepta glomerulis secus axem aliquantum elongatis (nec globosis) flores pedicellatos atque saepe in cymis minutis bracteolatis dispositos ferentibus differt; a var. canescenti axe florifero robusto 0.4–1 mm diametro (nec gracillimo usque 0.2 mm tantum diametro), perianthio fructifero longiore atque multo latiore 0.7–1.2 × 0.5–0.8 mm (nec usque 0.5 × 0.3 mm tantum) subglabro luteo-brunneo (nec badio-brunneo) et caule ad apicem adpresse piloso vel sparsissime (nec densissime) patente piloso differt. — Typus: J.F. Maxwell 891370 (holo E; iso L), northern Thailand, Chiang Mai, Chiang Dao, Doi Chiang Dao, north-eastern side of Sop Huay Pa Dang Huay Na Lao Forest Station, alt. 550 m, 5 Nov. 1989.
Herb or subshrub, 0.5–1.5 m tall, branched (from horizontal stems rooting at the nodes) or unbranched. Stems with hairs short, closely-adpressed, rarely also (eastern Himalayas) with sparse spreading hairs near apex. Stipules 0.5–1.2 cm long, hairy abaxially. Leaves slightly or moderately dimorphic in size and shape, length of ‘larger’ leaves 1.1–1.5 × that of ‘smaller’ ones; ‘larger’ leaves fairly narrowly ovate or elliptic-ovate, 5–20 by 3–10 cm, length 1.7–2.3 × width, marginal teeth 40–45 either side, acute fairly narrow up-curved, 1.25–3 by 2–5 mm, with width 1.5–1.7 × length; leaf apex with long or short acumen, up to 1.7 cm long; base not or slightly (rarely markedly) asymmetrical, short-cuneate or sometimes rounded; texture thin-chartaceous, but leaves often slightly bullate; adaxial surface with abundant ± spreading coarse stiff hairs; abaxial surface with hairs denser and finer; petioles (0.2–)0.25–0.5 × lamina length, hairy like the stem; ‘smaller’ leaves relatively broader with petiole shorter relative to lamina. Inflorescence-bearing axes with both sexes usually on same plant; male axes in lower axils, erect, often branched at base, 5–7 cm long, clusters well-spaced with few flowers; female axes in upper axils, ± erect but often pendent at apex, 5 –20 cm long, unbranched or with short (up to 1 cm) lateral sometimes male branches near base, clusters usually densely congested along axis, sometimes spaced 1–2(–3) mm apart; bracts 5–6 mm long; female clusters 2–4 mm diam in flower (4–6 mm in fruit) but mostly somewhat elongate, with many peduncles up to 1.5 mm long, these flattened, strap-shaped, often once or twice branched, each with conspicuous scattered straight hairs and bearing several flattened-pedicellate flowers; bracteoles subtending peduncles reddish, narrowly ovate or obovate up to c. 0.4 mm long, smaller bracteoles often also present along peduncles. Male flowers spreading-hairy. Female flowers up to c. 1 mm long excluding pedicel; stigma 0.5–1 mm long. Fruiting perianth broadly ovoid or subspherical 0.7–1.2 by 0.5–0.8 mm, moderately laterally flattened with indistinct or distinct marginal rim, without apical beak, rounded or slightly tapering at base, light yellowish brown (in dry state) and glabrous except for a few conspicuous hairs, like those on the pedicels, near apex. Achene filling fruiting perianth.
Distribution ― Northern India, Nepal, Burma, Thailand, Laos, Vietnam, South China.
Habitat & Ecology ― Primary or secondary evergreen or mixed seasonal forest or forest margins, often along tracks or in disturbed areas; dry or wet places and beside streams; 160–1300 m altitude.
Conservation status ― Least Concern (LC). Nearly 200 collections, many recent, clearly referable to this variety have been seen. It occurs in a wide range of habitat and does not appear to be currently at risk, but in future may become so with increasing pressure on habitats in Indochina.
Notes ― 1. Var. minuticymosa is the only variety known from Thailand. It is distinctive in its female flowers pedunculate, its short ± erect congested female axes and its yellowish almost glabrous broad round-based fruiting perianths and relatively narrow, thin-textured, leaves, short-cuneate with many teeth. Forms intermediate with var. macrostachya and var. canescens exist (see detailed discussion Note 5-ix under the species as a whole).
2. Although pedicellate female flowers on minute flattened peduncles are unusual, certain other species exhibit these sporadically (for example B. heterophylla and B. clidemioides , where they are not correlated with geographical distribution and are seen on material otherwise indistinguishable from that with sessile flowers); this character is therefore here considered to be of taxonomic significance only when correlated with other morphological characters and/or distribution.
3. As discussed under the subspecies (Note 8), this variety has sometimes been mistaken for B. ourantha .
4. The joint publication of this new taxon was accepted by N. Acharya and is partly based on his earlier unpublished findings.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.