Monanthotaxis gilletii (De Wild.) Verdc.

Hoekstra, P. H., Wieringa, J. J., Maas, P. J. M. & Chatrou, L. W., 2021, Revision of the African species of Monanthotaxis (Annonaceae), Blumea 66 (2), pp. 107-221 : 159

32. Monanthotaxis gilletii (De Wild.) Verdc. — Map 21

Monanthotaxis gilletii (De Wild.) Verdc.(1971b) 26. — Popowia gilletii De Wild. (1905a) 241. — Type: J. Gillet 3592 (holo BR0000008805294 ), Democratic Republic of the Congo, Bas-Congo, Madimba, environ de Kisantu, 1903.

Scandent shrub or liana, to 4 m long; young branches covered with erect, brown hairs 0.5–1 mm long; old branches blackish to dark reddish brown. Leaves: petiole 3–5.5 mm long, 0.8–1.2 mm diam, slightly grooved, indument slightly denser than on branches; lamina oblong-elliptic to elliptic-ovate or narrowly so, 6.2–13.5 by 2.7–4.9 cm, 1.7–2.9 times longer than wide, membranous to subcoriaceous, not punctate, glaucous below, above sparsely covered with erect hairs on primary vein, soon becoming glabrous, below sparsely covered with erect, brown hairs 0.5–1 mm long, more densely so on the primary vein, base rounded to subcordate, with thickened black margin, apex obtuse to sometimes slightly acute, secondary veins 6–13 per side, curving upwards, tertiary venation intermediate between percurrent and reticulate, slightly raised above. Inflorescences terminal or extra-axillary, composed of solitary flowers or sometimes 2-flowered rhipidia; sympodial rachis 5–11 mm long, covered with erect, yellowish brown hairs; pedicels 10–25 mm long, c. 0.5 mm diam, fruiting pedicels 25–35 mm long, 0.5–1.2 mm diam, covered with erect hairs c. 0.5 mm long; lower bract absent; upper bract large and leafy, broadly ovate, 7–17 by 6–16 mm, base semi-amplexicaul, sparsely covered with erect hairs; flower buds globose. Flowers bisexual; sepals connate, at the base almost forming a cup-like disc, depressed ovate, c. 1 by 3 mm, apex obtuse, densely covered with appressed to ascending hairs; receptacle 1.5–2.5 mm diam, flat, covered with hairs between carpels; petals yellowish to olive-reddish, 6, in two whorls, outer petals ovate, 5–8.1 by 3.6–4.3 mm, outside covered with ascending, yellow-brown hairs, inside densely covered with yellow, short hairs, glabrous at the base, inner petals rhombic, narrowed at the base, not covering stamens entirely in bud, 4.5–6 by 3.2–3.4 mm, outside densely covered with yellow, short hairs, inside glabrous at the base; stamens 15, in one or two whorls, free, linear-obconical, 1.6–1.9 mm long, filaments 0.3–0.6 mm long, thecae latrorse to introrse, connective truncate, subquadrate, pentagonal to squarish seen from above, prolonged outwards, staminodes absent; carpels 21–28, narrowly subcylindric-ellipsoid, c. 2.1 by 0.2–0.3 mm, glabrous, ovules 6, lateral, stigma elongate, c. 0.9 mm long, glabrous. Monocarps up to 12, yellow to red when ripe, narrowly ellipsoid to moniliform, 16–55 by 6–9 mm, glabrous or with few hairs at the base, apex apiculate, apiculum to 3 mm long, stipes 5–10 mm long. Seeds 1–4, ellipsoid, 7–9 by 5.5–6 mm, tawny, ends rounded, raphe not visible.

Distribution — Central African Republic, Democratic Republic of the Congo, Uganda.

Habitat & Ecology — In rain forest. Altitude: 1130–1243 m. Flowering: February, March, June, December; fruiting: January, May, October.

Preliminary IUCN conservation status — Endangered (EN): B2ab(iii). EOO: 1 460 344 km 2, AOO: 32 km 2. This species is known from 12 collections from 7 locations. The distribution is highly fragmented and it has only been collected once in the last 50 years.

Notes — 1. Monanthotaxis gilletii is easily recognizable by the leafy upper bract and the erect, reddish brown hairs of young stems, pedicels and lower leafside.

2. Specimens from Bas-Congo (including the type) have much smaller seeds than specimens of the Central African Republic, Uganda and the east of the Democratic Republic of the Congo.

Figures

Map 21 Distribution of Monanthotaxis foliosa (Engl.& Diels) Verdc. (●) and M. gilletii (De Wild.) Verdc. (■).