Mucuna havilandii Wiriad., 2016

Wiriadinata, H., Ohashi, H. & Adema, F., 2016, Notes on Malesian Fabaceae (Leguminosae-Papilionoideae) 16. The genus Mucuna, Blumea 61 (2), pp. 90-124 : 108-111

18. Mucuna havilandii Wiriad. , sp. nov. — Fig. 4

Twigs ferruginous tomentose. Leaflets 6.5–10.5 by 4–6.5 cm, terminal elliptic or obovate, lateral obliquely ovate. Inflorescences pseudopanicles or pseudoracemes, 1.5– 7 cm long. Calyx campanulate, 12–15 mm long, golden sericeous, tube 3–9 mm long. Blade of standard 20–23 mm long; blade of wing petals 3.3– 4 cm long; blade of keel petals 3.2– 4 cm long. Pods 8.5 by 3 cm, lamellae inconspicuous. — Type: Haviland s.n. (holo K), Sarawak, near Kuching

Liana. Twigs terete, striate, 2– 4 mm diam, ferruginous sericeous to pilose, glabrescent. Stipules caducous. Petioles 6.5– 11 cm long, grooved, ferruginous puberulous, glabrescent; rachis mostly as the petiole, 2–3.5 cm long; pulvinus 7–10 mm long. Stipellae acicular, 1.9–3.6 by 0.1–0.5 mm, with few hairs to sericeous at both sides. Leaflets: terminal elliptic or obovate, 8.5–10.5 by 4.5–6.5 cm, index 1.4–1.7, base truncate or rounded, apex acuminate, acumen 2 –10 mm long, above with scattered appressed hairs to thinly sericeous, below tomentose, midrib raised above, nerves slightly raised above, 4 –6 per side, 13–26 mm apart, anastomosing near the margin; lateral mostly as the terminal, obliquely ovate, 6.5–10.5 by 4–6.5 cm; pulvinus 4–8 mm long. Inflorescences axillary or raminascent, pseudopanicles or pseudoracemes, 1.5– 7 cm long, peduncle 0.2–0.7 cm long, ferruginous sericeous, branches 2.5– 4 cm long. Bracts to the brachyblasts ovate, c. 7.5 by 5 mm, outside ± pilose, inside glabrous. Brachyblasts 1–5 mm long. Bracts to the flowers ovate or elliptic, 11–21 by 5–6 mm, outside sericeous and with irritating hairs, inside thinly sericeous, caducous. Pedicels 11–15 mm long, ferruginous tomentose. Bracteoles ± elliptic or narrowly ovate, 11–15 by 3–5 mm, outside sericeous, inside sericeous and with irritating hairs. Calyx in bud cup-shaped, in anthesis broadly campanulate, 12–15 mm long, tube 3–9 mm long; upper lip triangular, 1–5 by 10–15 mm, lateral teeth triangular, 3.5–6 by 4–8 mm, median tooth triangular 6–9 by 5–6 mm; outside golden sericeous and with irritating hairs, inside sericeous. Corolla purplish. Standard: claw 3–4 mm long; blade broadly ovate, 20–23 by 15–20 mm, auricles 2 mm long, both sides glabrous. Wings: claw 5–7 mm long, outside with some hairs between claw and auricle, ciliate along both margins in upper part, inside with some hairs at upper margin at base; blade elliptic, 3.3–4 by 0.4–1.2 cm, rounded, auricle 2.5–3.5 mm long, lateral pocket 5–6 mm long, outside sericeous at auricle and just above, ciliate at lower margin at base, inside glabrous. Keel petals: claw 6.5–8.5 mm long, with some scattered hairs to ciliate along upper margin; blade narrowly elliptic, ± falcate at apex, 3.2–4 by 0.5–0.7 cm, auricles 2–3.5 mm long, hard part 7–9 mm long, lateral pocket 5–7 mm long, both sides glabrous, short-ciliate along upper margin. Stamens 3.8–4.5 cm long, tube 2.8–3.6 cm long, free part of filaments below versatile anthers 6–8 mm long, below basifixed ones 7–9 mm long; versatile anthers 0.9–1.1 by 0.7–1.2 mm, bearded, basifixed anthers 1.8–2 by 0.6–0.7 mm, outside ± villous at base more appressed upwards. Disc

l

d

0.7–1.1 mm high. Ovary 5 mm long, stipe 0.9–1.0 mm long, sericeous and with irritating hairs; ovules 2; style 3.5–3.8 cm long, sericeous, thinning upwards, upper part glabrous. Pods flattened ellipsoid, 8.5 by 3 cm, upper wing c. 7 mm wide, lower wing 6 – 9 mm wide, lamellae inconspicuous, more distinct at lower margin in basal part, interrupted in the middle, up to 2 mm high, the lower part of the lamellae more developed than the upper part, valves with few hairs and some irritating hairs. Seeds orbicular, 1.5 by 1.0 cm; hilum> 1/2 the circumference.

Distribution — Malesia: Borneo: Sarawak, Sabah.

Habitat & Ecology — Lowland or secondary forest. Flowering: July, November.

Note — This species is ± similar to M. acuminata but differs in the ferruginous indumentum of the lower surface of the leaflets, the less well developed calyx teeth, the two-seeded pods with at least some lamellae. Mucuna acuminata has ± smooth pods and usually more than 2 seeds. The type of M. havilandii (Haviland s.n.) is a flowering specimen to which an old pod (collected from the forest floor under or near the specimen?) is added. This pod is very different from the pods of other Bornean species of Mucuna in the inconspicuous, interrupted lamellae. One of the flowers of the specimen has a very young pod, which shows after partial removal of the indumentum obscure lamellae. This young fruit does not contradict the idea that the pod added to Haviland s.n. belongs to the present species.

Figures

Fig. 4 Mucuna havilandii Wiriad. a. Twig with leaves and an inflorescence; b. detail of stem indumentum; c. bud; d. detail of lower leaflet surface; e. detail of upper leaflet surface; f. calyx opened, from outside; g. standard; h. wing petal; i. keel petal; j. stamens, sheath opened; k. ovary and style; l. fruit; m. detail of fruit indumentum (a, b, d. e: SAN 151208 (Pereira et al.); c, f–m: Haviland 967). — Drawing Margaret Tebbs.