Xylopia gilbertii Boutique, Bull. Jard. Bot. Etat Bruxelles 21: 110, 1951

Couvreur, Thomas L. P., Dagallier, Leo-Paul M. J., Crozier, Francoise, Ghogue, Jean-Paul, Hoekstra, Paul H., Kamdem, Narcisse G., Johnson, David M., Murray, Nancy A. & Sonke, Bonaventure, 2022, Flora of Cameroon - Annonaceae Vol 45, PhytoKeys 207, pp. 1-532 : 459-460

Xylopia gilbertii Boutique, Bull. Jard. Bot. Etat Bruxelles 21: 110, 1951

Map 17H

= Xylopia ardua Sillans, Rev. Int. Bot. Appl. Agric. Trop. 33: 555, 1953. Type. Central African Republic: Lobaye, Boukoko, Tisserant C. 2329, Dec 1951: lectotype, designated Johnson and Murray (2018), p.110: P[P00169140]; isotypes: BM[000510989]; P[P00169141, P00169142, P00169143]; US[2679729].

Type.

Democratic Republic of the Congo. Tshopo Region ; Yangambi, plateau de la Luweo, Louis J.L.P. 6777, Nov 1937: holotype: BR[BR0000008824738]; isotypes: B[B100249561]; BM K[K000542217]; P[P00169152] ; US.

Description.

Tree, up to 40 m tall, d.b.h. up to 40 cm; buttresses present, small. Old branches sparsely pubescent with erect hairs, young branches pubescent with persistent erect hairs 0.3-0.8 mm long. Leaves: petiole 3-4 mm long, ca. 1 mm wide, densely erect pubescent, slightly grooved, blade inserted on the side of the petiole; blade 4.2-9.7 cm long, 2-3.3 cm wide, elliptic-oblong to lanceolate, occasionally oblong or ovate, apex acute to rounded, base cuneate to rounded, papyraceous to subcoriaceous, below sparsely pubescent with erect hairs when young and old, above glabrous when young, glabrous to pubescent when old, slightly discolorous; midrib sunken or flat, above densely pubescent when young and old, below pubescent when young and old; secondary veins 7 to 14 pairs, pubescent above; tertiary venation reticulate. Individuals bisexual; inflorescences ramiflorous on young foliate branches, axillary, peduncle 1.5-2.5 mm long. Flowers with 9 perianth parts in 3 whorls, 1 to 6 per inflorescence; pedicel 1-2 mm long, 1-2 mm in diameter, densely pubescent; in fruit 5-10 mm long, 2-3 mm in diameter, sparsely pubescent; bracts 2, evenly spaced, 2-4 mm long, 2-3 mm wide; sepals 3, valvate, free to basally fused, ca. 2 mm long, 3-4 mm wide, reniform to semicircular, apex acute to rounded, base truncate, densely pubescent outside, glabrous inside; petals free, subequal, fawn-olive, brown-violet, or purple; outer petals 3, 6.6-11 mm long, 2.4-4.4 mm wide at base, lanceolate to ovate, apex obtuse, base broad and concave, densely pubescent outside, pubescent but glabrous towards center inside; inner petals 3, valvate, 5.8-9.3 mm long, 3-4 mm wide at base, lanceolate, apex acuminate to obtuse, base broad and concave, with round glandlike thickenings on margins, pubescent outside, pubescent but glabrous towards center inside; stamens 80-130, in 6 to 7 rows, ca. 1 mm long, clavate to oblong; connective apex shield-like to capitate, glabrous; carpels 6 to 11, ovary 1-2 mm long, stigmas connivent, linear, 1.5-2.2 mm long, sparsely pubescent. Monocarps stipitate, stipe 5-13 mm long, 1-4 mm in diameter; monocarps 1 to 10, 25-37 mm long, 10-13 mm wide, oblong, apex rounded or with a blunt beak 1-1.5 mm long, glabrous to sparsely pubescent with erect hairs, sparsely verrucose and weakly wrinkled when dried, reddish or purplish green outside, endocarp color unknown; seeds up to 6 per monocarp, in a single row, 7-10 mm long, 4-7 mm wide, ellipsoid; sarcotesta red in vivo; aril absent.

Distribution.

From southern Cameroon to northern Gabon and Central African Republic and east to the northeastern Democratic Republic of the Congo; in Cameroon known from the East and South regions.

Habitat.

An uncommon or infrequently collected species, in submontane rain forests. Altitude 470-900 m. a.s.l.

Local and common names known in Cameroon.

None recorded.

IUCN conservation status.

Vulnerable (VU) ( Cosiaux et al. 2019a z).

Uses in Cameroon.

None reported.

Notes.

Xylopia gilbertii is characterized by the sparse but persistent erect hairs of the young branches, leaves, and monocarps, the relatively broad but small flowers on short pedicels, and the rounded marginal glandlike thickenings on the inner petals. The relatively short broad outer petals are shared only with X. staudtii and X. africana in the Cameroon flora.

Specimens examined.

East Region: A 9 km à l’ouest de Yenga Port Gentil village situé à 25 km au NNE de Moloundou, 2.34°N, 15.26°E, 21 April 1971, Letouzey R. 10701 (P,YA). South Region: Près Akonetye PK 95 sur route Mintom I (70 km E de Djoum)-Mbalam (140 km ESE de Djoum), 2.67°N, 12.87°E, 22 January 1973, Letouzey R. 11876 (P,WAG,YA) .

Figures

Map 17. A Uvariopsis zenkeri B Xylopia aethiopica C Xylopia africana D Xylopia aurantiiodora E Xylopia calva F Xylopia cupularis G Xylopia elliotii H Xylopia gilbertii I Xylopia hypolampra. White borders represent region limits in Cameroon; green patches represent protected areas (see methods and Suppl. material 1: Fig. S 1).