Xylopia rubescens Oliv., Fl. Trop. Afr. 1: 30, 1868

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 : 484-487

Xylopia rubescens Oliv., Fl. Trop. Afr. 1: 30, 1868

Fig. 151 ; Map 19A

≡ Xylopicrum rubescens (Oliver) Kuntze, Revis. gen. pl. 1: 8, 1891.

= Xylopia klaineana Pierre ex Engler & Diels, Monogr. Afrik. Pflanzen-Fam. 6: 59-60. 1901. Xylopia rubescens Oliver var. klaineana (Engler & Diels) Pellegrin, Bull. Soc. Bot. France, Mém. 31: 70. 1949. Type. Gabon. Without definite locality, Klaine T.-J. 1327, Oct 1898: holotype: P[P00169139]; isotypes: B[B100154150], P[P00169138]).

= Xylopia humilis Engl. & Diels, Monogr. Afrik. Pflanzen.-Fam. 6: 60, 1901. Type. Liberia. Grand Bassa County, Fishtown bei Granbassa, Dinklage M.J. 2006, 27 Aug 1898: lectotype, designated by Johnson and Murray (2018), p. 49: B[B10 0154147]; isotypes: A[A00061927, A00062417]; B[B100154145, B100154146, B1001541480]; K[K000199074, K000199075, K000199076].

= Xylopia batesii Engl. & Diels, Monogr. Afrik. Pflanzen.-Fam. 6: 62, 1901. Type. Gabon. Angom, 70 engl. Meilen östlich von Gabun, Bates G.L. 561, Oct 1896: holotype: K[K000199058]; isotypes: BM[BM000510769]; G[G00190711]; P[P00169131, P00169132].

= Xylopia butayei De Wild., Ann. Mus. Congo, Bot. sér. 4, 1: 33, 1902. Type. Democratic Republic of the Congo. Kongo Central, Malela (Bas-Congo), Butaye R. 2239, no date: holotype: BR; isotype: BR[BR0000008825391].

= Xylopia zenkeri Engl. & Diels, Bot. Jahrb. Syst. 39: 480, 1907. Type. Cameroon. South Province, Bipindi, Zenker G.A. 2827, Mar 1904: holotype B[B 100154149]; isotypes: BM[BM 000511041]; G [00190712, G 00190713]; GOET[GOET 005735]; HBG[HBG 502474]; K[000199060]; L [0196246]; M[M 0107919]; P[P00169131]; S[S 07-13458]; WAG[WAG 0065882]; WU[WU 0025792].

= Xylopia gossweileri Exell, J. Bot. Suppl. 6: 64, 1926. Type. Angola. Cabinda, Pango Munga, Mayumbe, Gossweiler J. 6222, no date: holotype: BM[M000511046].

Type.

Nigeria. Rivers state; Old Calabar, Thomson W.C. 53, no date: holotype: K[K000199073] .

Description.

Tree, up to 30 m tall, d.b.h. up to 70 cm; stilt roots present, up to 2 m on the trunk. Old branches glabrous, turning grayish white, young branches glabrous to pubescent with appressed golden hairs 0.2-0.5 mm long. Leaves: petiole 5-12 mm long, ca. 2 mm wide, glabrous to sparsely pubescent, grooved, blade inserted on the side of the petiole; blade 7.3-21.3 cm long, 3.6-8.4 cm wide, oblong, elliptic, or oblanceolate, apex acuminate to cuspidate, acumen 0.2-1.5 cm long, base cuneate to rounded, decurrent, papyraceous to subcoriaceous, below sparsely appressed-pubescent, rarely glabrous, above glabrous, strongly discolorous; midrib flat to sunken, above glabrous when young and old, below glabrous to sparsely pubescent when young, glabrous when old; secondary veins 8 to 16 pairs, glabrous above; tertiary venation reticulate. Flowers bisexual with 9 perianth parts in 3 whorls. Individuals bisexual; inflorescences ramiflorous on young foliate or more often clustered on older leafless branches, axillary, peduncle 1.5-2.5 mm long. Flowers with 9 perianth parts in 3 whorls, 1 to 3 per inflorescence; pedicel 4-9 mm long, ca. 1 mm in diameter, pubescent; in fruit 9-15 mm long, 2-7 mm in diameter, glabrous; bracts (2)3(5), evenly spaced, 1-3 mm long, 1-3 mm wide; sepals 3, valvate, basally fused, 2-4 mm long, 3-4 mm wide, ovate to broadly triangular, apex acute, base truncate, green, sericeous outside, glabrous inside; petals free, outer petals much longer than inner; outer petals 3, 17.6-35 mm long, 2.5-5.1 mm wide at base, linear, apex acute, base broad and concave, yellow, pubescent outside, pubescent and glabrous towards the base inside; inner petals 3, valvate, 3.5-6.7 mm long, 2.2-4.6 mm wide, ovate to rhombic, apex acuminate, base broad and concave, red with cream base and apex, pubescent outside, pubescent and glabrous towards the base inside; stamens 70 to 77, in 4 to 5 rows, ca. 2 mm long, clavate to oblong; connective apex shield-like, glabrous; carpels 4 to 12, ovary 1-2 mm long, stigmas loosely connivent, linear, 1.4-2.9 mm long, with glandular appendages. Monocarps stipitate, stipe 4-20 mm long, 2-6 mm in diameter; monocarps 1 to 15, 41-16 mm long, 6-12 mm wide, narrowly oblong, somewhat falciform and strongly torulose to moniliform, apex with a distinct beak up to 5 mm long, glabrous, verrucose and wrinkled when dried, black or dark purple outside, endocarp pink to scarlet; seeds 1 to 7 per monocarp, in a single row, 10-20 mm long, 6-11 mm wide, ellipsoid; sarcotesta absent; aril present, brushlike, unlobed, red to orange.

Distribution.

A widespread species with a disjunct distribution in West Africa, from Guinea-Bissau to Ghana, and in Central Africa from Nigeria to southern South Sudan and south to northern Angola and Mozambique; in Cameroon known from East, South, Littoral and regions.

Habitat.

A common species, in a range of wetland habitats, including gallery and other riparian forests, swamp forest, Raphia swamps, and pond edges. Altitude 0-900 m a.s.l.

Local and common names known in Cameroon.

ntua (Fleury 33135), odjobi (Letouzey 1611), odjobi nzam ( Focho et al. 2010), odzobé (Fleury 33135), ôjobi (Bates 1317).

IUCN conservation status.

Least Concern (LC) ( Cosiaux et al. 2019b e).

Uses in Cameroon.

None reported.

Notes.

Xylopia rubescens is readily recognized by the combination of relatively large leaves with decurrent bases, which often have an orange-red color on the lower surface of the leaf in dried specimens, branches with grayish white, narrow flowers that are often clustered on leafless porolder branches, and distinctly torulose to moniliform monocarps. Throughout its wide range it is a wetland species, and one of the few Xylopia species with stilt roots. The short inner petals and brushlike arils distinguish X. rubescens from X. aethiopica , with which it is sometimes confused.

Specimens examined.

East Region: Marecage du Niagoul entre Koumbou et Miambo, 4.27°N, 12.9°E, 13 April 1959, Letouzey R. 1611 (P,YA). Littoral Region : Duala, 4.05°N, 9.71°E, 01 June 1917, Fleury F. 33135 (P). South Region: Batanga, 2.86°N, 9.889°E, 20 September 1945, Aubréville A. 125 (P); Bitye Yaunde, 3.02°N, 12.37°E, 01 January 1919, Bates G.L. 1317 (BM,MO); N´Koemvone, 2.8°N, 11.13°E, 11 April 1975, de Wilde J.J.F.E 8166 (B,BR,K,MO,P,WAG,YA); Près Akok Bikélé, 3.8°N, 12.7°E, 03 March 1962, Letouzey R. 4464 (YA); Bipindi, 3.08°N, 10.41°E, 01 January 1904, Zenker G.A. 2827 (G,L,M,WAG). Unknown region: Vuneli, 01 February 1928, Hédin L. 1668 (P, OWU) .

Figures

Map 19. A Xylopia rubescens B Xylopia staudtii C Xylopia talbotii D Xylopia thomsonii E Xylopia villosa. White borders represent region limits in Cameroon; green patches represent protected areas (see methods and Suppl. material 1: Fig. S 1).

Figure 151. Xylopia rubescens A flowering branch B flower, outer petals removed C detail of receptacle, petals removed D outer petal, outer side E inner petal, outer and inner sides F stamen, front view G staminode H carpel, side view and detail of ovules I fruit J detail of venation lower side of leaf K monocarp L seed, side view M part of aril A-H from Le Testu 9019 I from Aubreville 1511 J-M from Klaine 1327. Drawings by Helene Lamourdedieu, Publications Scientifiques du Museum national d'Histoire naturelle, Paris; modified from Le Thomas (1969 b; pl. 28, p. 161).