Monanthotaxis bokoli (De Wild. & T.Durand) 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 : 133-135

9. Monanthotaxis bokoli (De Wild. & T.Durand) Verdc. — Fig. 7a–g ; Map 6

Monanthotaxis bokoli (De Wild.& T.Durand) Verdc.(1971b) 24. — Xylopia bokoli De Wild.& T.Durand (1900) 2. — Popowia bokoli (De Wild.& T.Durand) Boutique (1951a) 349. — Lectotype (designated here): A.P. Dewèvre 785 (lecto BR (BR0000024941433) not seen; isolecto BR0000008804020, BR0000008804358), Democratic Republic of the Congo.

Popowia iboundjiensis Pellegr. (1949) 212. — Lectotype (designated here): G.M.P.C. Le Testu 5729 (lecto P ( P00362791 ); isolecto BM000553827 , LISC000388 , P00362789 , P00362790 ), Gabon, Ngounié, Ndingui, Muller- ville, 11 Nov.1925;other syntype: G.M.P.C. Le Testu 8626 ( BM000553826 , P01954740 , P01954741 ), Gabon, Ogooué-Lolo, region de Lastoursville, Mont Iboundji , 27 Dec. 1930.

Scandent shrub or liana, to 6 m long; young branches densely covered with erect, reddish brown hairs 0.4–1.3 mm long, becoming glabrous; old branches blackish, sometimes with reddish tint. Leaves: petiole 2.5–6.3 mm long, 0.9–1.3 mm diam, terete, indument as on branches; lamina oblong-elliptic, 4.4–12.6 by 2.3–6.9 cm, 1.6–2.6 times longer than wide, subcoriaceous to chartaceous, slightly punctate, glaucous above, above covered with appressed, white hairs 0.5–1 mm long, soon becoming glabrous, primary vein above covered with ascending to erect, yellow hairs c. 0.2 mm long, below sparsely covered with ascending to erect, reddish brown hairs 0.5–0.8 mm long, slightly more densely so on primary vein, base subcordate, glands hardly visible, apex rounded or acute, secondary veins 7–11 per side, straight then halfway curving upwards, tertiary venation percurrent, hardly visible above. Inflorescences extra-axillary, leaf-opposed or terminal, composed of solitary flowers; sympodial rachis absent; pedicels 11–24 mm long, 0.5–0.9 mm diam, fruiting pedicels 0.9–1.1 mm diam, sparsely to densely covered with erect, reddish brown hairs 0.5–0.6 mm long; lower bracts absent; upper bract in the lower half of the pedicel, ovate, 1.4–2.2 by 0.7–0.9 mm, indument as on pedicel; flower buds globose, but ovoid before anthesis. Flowers bisexual; sepals connate at the base, depressed ovate, 2.8–4.1 by 4.5–6.8 mm, apex rounded, covered with ascending, yellow-brown hairs, persistent in fruit; receptacle 3.7–5.8 mm diam, flat; petals colour in vivo unknown, 6, in two whorls, outer petals ovate, 15–19 by 8.4–10.8 mm, outside and apical part and margins of inside densely covered with yellowish hairs, inner petals lanceolate, c. 13 by 4.5–5.2 mm, outside glabrous, except for a few hairs near the apex; stamens 24–32, in three or four whorls, free, obovoid, 1–1.1 mm long, filaments 0.3–0.4 mm long, thecae latrorse to extrorse, connective truncate, prolonged inward, hiding thecae, slightly papillate, staminodes absent; carpels 27–38, subcylindric, c. 2.7 by 0.4 mm, glabrous or with a few hairs at the base, ovules 4 or 5, lateral, stigma subcylindric, c. 0.9 mm long, glabrous. Monocarps 1–25, yellow, maturing orange, subcylindric, 26–65 by 5–8 mm, slightly verrucose, glabrous or with a few hairs on the stipe, apex rounded or apiculate, apiculum to 4 mm long, stipes 7–10(–25) mm long. Seeds 1–4, cylindric, 14–21 by 4–6 mm, ochre-brown, apex flattened, rounded or apiculate, raphe not visible.

Distribution — Cameroon, Central African Republic, Democratic Republic of the Congo, Equatorial Guinea, Gabon.

Habitat & Ecology — In swamp forests, gallery forests, primary and secondary rain forests.Altitude: 350– 800 m. Flowering: March to December; fruiting: all year round.

Vernacular name — Democratic Republic of the Congo: Bocodji (A.P. Dewèvre 785).

Preliminary IUCN conservation status — Least concern (LC). EOO: 2 157 212 km 2, AOO: 108 km 2. This species is known from many localities including a few national parks. Therefore, M. bokoli is currently not under threat of extinction.

Notes — 1. Monanthotaxis bokoli resembles M. ferruginea and both species share a dense indument of erect, reddish brown hairs on the branches and leaves and glabrous carpels. Monanthotaxis bokoli can, however, easily be distinguished by the much larger flowers, almost glabrous inner petals and subcylindric seeds and monocarps with long stipes. However, the leaves of M. ferruginea are highly variable between different populations and those on specimens from eastern Africa may look highly similar to M. bokoli .

2. A specimen from southwest Gabon (F.J. Breteler 14616) differs from the other specimens of M. bokoli in having shorter hairs and slightly more obovate leaves.

3. The lectotype designated here was not seen. This sheet has been appointed by Johnson & Murray (2018) as the holotype, however, they should have stated that it is a lectotype as previous authors did not indicate which of the 3 sheets is the holotype.

Figures

Map 6 Distribution of Monanthotaxis bidaultii P.H.Hoekstra (■, D means uncertain det) and M. bokoli (De Wild. & T.Durand) Verdc. (●, O means uncertain dets).

Fig. 7 a–g. Monanthotaxis bokoli (De Wild. & T.Durand) Verdc. a. Flowering branch; b. detail leaf abaxially;c. flower with three petals removed; d. outer petal, inside view; e. inner petal, inside view; f. stamen; g. carpel and longitudinal section of carpel. — h–m. Monanthotaxis pellegrinii Verdc. h. Flowering branch; i. flower with three petals removed; j. outer petal, inside view; k. inner petal, inside view; l. stamen; m. carpel and longitudinal section of carpel (a–g: Le Testu 5729; h–m: Le Testu 9028). — Modified from Le Thomas (1969) plate 41.