Boehmeria pilosiuscula var. pilosiuscula

Wilmot-Dear, C. M. & Friis, I., 2013, The Old World species of Boehmeria (Urticaceae, tribus Boehmerieae). A taxonomic revision, Blumea 58 (2), pp. 85-216 : 201

1. Female and bisexual axes, at least some on plant, with flower-bearing part 3–10 cm long; clusters contiguous along part of length but usually distinct; leaves mostly bullate, often relatively thick, marginal teeth either more than 35 either side or ≥ 2 mm long; branched (entirely male axes present or not). — India; Sri Lanka; Burma; Indonesia; Philippines............................... a. var. pilosiuscula a. var. pilosiuscula — Fig. 38a–i ; Map 40

Boehmeria platyphylla D.Don var. zeylanica Wedd.(1869) 211. ― Boehmeria macrophylla Hornem.var. zeylanica (Wedd.) Wadhwa (1999) 265. ― Type: Thwaites 2197 (lecto K; isolecto CAL, G, P), Sri Lanka. – See Note 1.

Boehmeria humilis Miq.(1851) 33. ― Boehmeria pilosiuscula (Blume) Hassk. var. humilis (Miq.) Blume (1857) 223. ― Boehmeria platyphylla D.Don var. humilis (Miq.) Wedd. (1869) 212. ― Boehmeria caudata (Burm.f.) J.J.Sm. var. humilis (Miq.) J.J.Sm. (1910) 717. ― Type: Junghuhn s.n. (holo L), Indonesia, Jawa [Java], Mt Medin, Ungaran.

Boehmeria pilosiuscula (Blume) Hassk. var. procera Blume (1857) 223. ― Type: Not indicated or traced.

Shrub. Leaves (3–)5–12(–15) cm long, marginal teeth (25–)35– 45, either broader or more numerous in larger leaves, 1–2 by 2–4 mm; thin- or thick-textured, but leaves ± bullate with conspicuous reticulation, hairs adaxially ± spreading, often with conspicuous bulbous base giving rough texture. Female or bisexual inflorescence-bearing axes (2–)3–6(–10) cm long, the longest ones sometimes drooping in upper part, often with intermittent gaps between groups of clusters; entirely or predominantly male axes occasionally also present, 4–6 mm long, branched in basal quarter, clusters contiguous or spaced up to 1 mm apart, 2–3 mm diam, with 2–5(–10) flowers.

Distribution ― India, Sri Lanka, Burma, Indonesia (Sumatera, Jawa, Borneo, Nusa Tenggara [Lesser Sunda Islands]), Philippines (Luzon).

Habitat & Ecology ― Clearings in disturbed areas of evergreen primary forest; sea level– 1650 m altitude.

Notes ― 1. Hooker (1888: 578) states about the collection Thwaites 2197 that it is “mixed with var. scabrella ” and Wadhwa writes the same on the Peradenya (PDA) sheet of this collection. Wadhwa’s determination on the duplicate of this collection at K indicates that parts of the collection represents B. rugosissima , but in our opinion all the material in the duplicates we have seen represents B. pilosiuscula . In order to avoid further doubt, we designate the K duplicate as lectotype.

2. Few collections (sometimes only one) have been seen from most localities, suggesting that it is under-collected.

3. It differs from var. suffruticosa in leaves with teeth either more numerous or larger, mostly bullate, often larger or thicker-textured, inflorescence-bearing axes usually longer with clusters often less crowded together along the axis, the flower-bearing part of at least some axes 3–10 cm (rather than ≤ 2 cm) and the occasional presence of branched mainly male axes.

4. Var. pilosiuscula is often less easy than is var. suffruticosa to distinguish from B. virgata subsp. macrophylla var. scabrella . As discussed above in Note 8 under the species as a whole the only absolutely distinguishing features from B. virgata subsp. macrophylla var. scabrella are the mixed stem indumentum, ‘solid’ female clusters, female flowers with a truncate apex and the presence of male clusters at tips of mainly female-axes.

5. Specimens with somewhat bullate leaves can be confused with small-leaved forms of the sympatric B. rugosissima . Fertile material is easily distinguished, with inflorescence-bearing axes always unisexual and both sexes are usually several-branched near their base with well-spaced clusters and the fruiting perianth of B. rugosissima is not truncate at its apex. Sterile material can be distinguished by leaves ± symmetrical and either much larger or thick-textured and deeply and closely rugose-bullate, or both; stipules are also often much larger. Two clearly mixed collections exist, suggesting that the two species can be found growing together; intermediate material of possible hybrid origin has also been seen. See under B. rugosissima (Note 4) for more detailed discussion.

Figures

Map 40 Distribution of Boehmeria pilosiuscula (Blume) Hassk. var. pilosius­ cula (●) and intermediates between B. pilosiuscula var. pilosiuscula and var. suffruticosa (ä).

Fig. 38 a–i: Boehmeria pilosiuscula (Blume) Hassk. var. pilosiuscula. a. Habit of stem with bisexual and female inflorescence-bearing axes; b. lower node of stem with branched male inflorescence-bearing axis; c. detail of stem showing two kinds of spreading hairs; d. leaf; e. leaf, detail of abaxial surface; f. detail of stem and stipule; g. upper part of bisexual inflorescence-bearing axis with congested female flower-clusters (inflorescences) below and few-flowered male clusters (inflorescences) at apex; h. male bud; i. fruiting perianth. — j: Boehmeria pilosiuscula var. suffruticosa Acharya, Friis & Wilmot-Dear. Habit of stem with bisexual and female inflorescence-bearing axes (a, e, f, h: Sinclair 10053, K; b: de Vriese s.n., L; c, d: Kostermans 18171, K; g: Henry 12370, K; i: Gammie 190, K; j: Henry 12696, K). — Scale bars: a, b, d, j = 2 cm; c, g-i = 1 mm; e, f = 2 mm.