Xylopia thomsonii Oliv., Fl. trop. Afr. 1: 31, 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 : 491-494

Xylopia thomsonii Oliv., Fl. trop. Afr. 1: 31, 1868

Fig. 153 ; Map 19D

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

= Xylopia pyrifolia Engl., Pflanzenw. Ost-Afrikas C: 179, 1895. Type. Democratic Republic of the Congo. Ituri Province, Bataibo am Duki, Stuhlmann F.L. 2781, 7 Nov 1891: holotype: B[100153155].

= Xylopia tenuifolia Engl. & Diels, Notizbl. Konigl. Bot. Gart. Berlin 2: 298, 1899; Xylopicrum tenuifolium (Engler & Diels) Kuntze, Deutsch. Bot. Monatsschr. 21: 173-174, 1903. Type. Cameroon. South-West Region, Urwald zwischen Mowange und Isongo, Preuss C.G.T. s.n., Mar 1897: B, apparently destroyed.

= Xylopia seretii [" sereti "] De Wild., Ann. Mus. Congo Belge, Bot. sér. 5, 3: 79, 1909. Type. Democratic Republic of the Congo. Haut-Uele, bords d’une riviere sur la route de Faradje à Vankerkhovenville, Seret F. 555, 12 Apr 1906: holotype: BR[BR0000024941396]; isotype: BR[0000008824370].

Type.

Nigeria. Rivers state; Old Calabar, Thomson W.C. 53, no date: holotype: K[000199064] .

Description.

Scandent shrub up to 10 m tall or rarely an upright tree, d.b.h. up to 17 cm; stilt roots and buttresses absent. Old branches pubescent, young branches pubescent with erect dull gray to brown hairs 0.1-1.3 mm long. Leaves: petiole 2-6 mm long, ca. 1 mm wide, sparsely pubescent, grooved, blade inserted on the side of the petiole; blade 8.4-13.7 cm long, 2.5-4.7 cm wide, lanceolate, elliptic to oblong, or oblong-oblanceolate, apex acuminate, acumen 0.3-1.6 cm long, base cuneate to rounded, papyraceous, below glabrous to sparsely pubescent when young, glabrous to sparsely pubescent when old, above glabrous when young and old, generally discolorous; midrib sunken, above pubescent when young, glabrous when old, below pubescent when young and old; secondary veins 11 to 17 pairs, glabrous above; tertiary venation reticulate. Individuals bisexual; inflorescences ramiflorous on young foliate or old leafless branches, axillary, peduncle absent. Flowers with 9 perianth parts in 3 whorls, 1 (2) per inflorescence; pedicel 3-8 mm long, ca. 1 mm in diameter, pubescent; in fruit 5-12 mm long, 2-8 mm in diameter, sparsely pubescent; bracts 3 to 6, overlapping toward pedicel base, 2-4 mm long, 2-3 mm wide; sepals 3, valvate, basally fused, 2-4 mm long, 3 mm wide, triangular to ovate, apex acute to obtuse, base truncate, pubescent outside, glabrous inside; petals free, subequal; outer petals 3, 14.6-49 mm long, 2.4-3.8 mm wide at base, linear, apex acute to obtuse, base broad and concave, cream to white, pubescent towards base outside, pubescent with glabrous base inside; inner petals 3, valvate, 16-33 mm long, 2.1-3.2 mm wide at base, linear, apex acute, base broad and concave, cream to white, pubescent with glabrous base on both sides; stamens ca. 200, in 4 to 6 rows, 1-2 mm long, oblong; connective apex shield-like, glabrous; carpels 7 to 13, ovary ca. 1 mm long, stigmas connivent, linear-falcate, 1.8-3.4 mm long, pubescent. Monocarps stipitate, stipe 3-11 mm long, 2-3 mm in diameter; monocarps 5 to 10(12), 21-65 mm long, 6-12 mm wide, narrowly oblong, weakly torulose, apex obtuse or with a beak 1-4 mm long, glabrous, verrucose or lenticellate (in vivo) and smooth to longitudinally wrinkled when dried, green outside, endocarp red to red-purple; seeds up to 9, commonly 4-8 per monocarp, in a single row, 9-12 mm long, 6-7 mm wide, ellipsoid; sarcotesta thin, waxy, green in vivo; aril absent.

Distribution.

A widespread species in central Africa, from Nigeria to South Sudan and south to northeastern Angola; in Cameroon known from East, South, Central, Littoral, South-West, West and Adamaoua regions.

Habitat.

A common species with a wide ecological amplitude, in the understory of primary or old secondary rain forest or gallery forest, occasionally in marshy forest or forest edges near water. Altitude 0-1300 m a.s.l.

Local and common names known in Cameroon.

akwi (Ewondo, Breteler 931).

IUCN conservation status.

Least Concern (LC) ( Harvey-Brown 2019m).

Uses in Cameroon.

None reported.

Notes.

Xylopia thomsonii is a scandent shrub or occasionally a small tree occurring in lowland forests, usually near water. The relatively short pedicels with persistent overlapping bracts, and 1-flowered inflorescences are characteristic. Xylopia thomsonii was formerly included in Xylopia acutiflora (Dunal) A. Rich., which is now considered to be restricted to West Africa from Sierra Leone to southwestern Ivory Coast. In Cameroon it is most similar to X. monticola and X. elliotii ; see the key for distinctions among those species.

Selected specimens examined.

Adamaoua Region: At Sabal Haleo 62 km NE de Tibati, 6.78°N, 13.17°E, 11 April 1983, Asonganyi J.N. 632 (P,YA); A 10 km à l’ouest de Bagodo, 6.42°N, 13.38°E, 28 July 1966, Letouzey R. 7563 (YA); Banyo, 6.75°N, 11.82°E, 08 June 1967, Letouzey R. 8552 (P,YA). Central Region: Ndanan I to Ndangan I Forest on path left of road after bridge, site of 25 m × 25 m plot, 3.61°N, 11.59°E, 16 March 2004, Cheek M. 11690 (K,YA); Ca 50 km S of Badjob ca 60 km SW of Eséka Along the Nyong-River, 3.68°N, 10.68°E, 20 March 1964, de Wilde W.J.J.O 2172 (B,BR,K,MO,P,WAG,YA); Syzygeraie près Malandi, 3.57°N, 11.22°E, 06 December 1959, Letouzey R. 2423 (P,YA); Près des lacs de Boubala, 5.75°N, 11.9°E, 13 December 1960, Letouzey R. 2566 (P,YA); Rive boisée de la Sanaga près Mbargue, 4.9°N, 13.08°E, 27 January 1960, Letouzey R. 2824 (P,YA). East Region: Bétaré Oya 5 km along road to Bertoua, 5.5°N, 14.1°E, 17 February 1960, Breteler F.J. 1063 (P,WAG,YA); Goyoum, 5.22°N, 13.38°E, 27 January 1961, Breteler F.J. 931 (BR,K,P,WAG); Mbussa, 6°N, 14.38°E, 29 April 1914, Mildbraed G.W.J. 9069 (K); Route Esseleke, 4.58°N, 13.68°E, 15 February 1956, Nana P. 479 (P); Sangha River (international frontier) collected 30 km from Libongo southwards, 2.5°N, 16.06°E, 27 July 1987, Thomas D.W. 7281 (YA). Littoral Region: 8 km W of Massok, 4.13°N, 10.47°E, 27 March 1965, Leeuwenberg A.J.M. 5217 (B,BR,C,GC,K,LUAI,MO,P,WAG,YA). North-West Region: Anyajua, 6.18°N, 10.36°E, 12 December 1998, Cheek M. 9923 (K,WAG,YA); Bamenda Distr Fonfuka, 6.53°N, 10.48°E, 01 May 1931, Maitland T.D. 1731 (K). South Region: Bitya near R Ja, 3.02°N, 12.37°E, 01 January 1921, Bates G.L. 1852 (P); S bank of Lobé R SE of Gr Batanga ferry, 2.88°N, 9.892°E, 11 October 1969, Bos J.J. 5475 (BR,C,K,LD,P,WAG,YA); Ca 10 km SW of Ambam S of Ebolowa On N bank of Ntem-River, 2.38°N, 11.28°E, 02 March 1964, de Wilde W.J.J.O 2043 (B,BR,K,MO,P,WAG,YA); Colline de Mill (5 km NE Lolodorf), 3.23°N, 10.73°E, 26 January 1974, Letouzey R. 12797 (P,YA); Ngoasik (10 km SSE Ambam) rive du Nt, 2.28°N, 11.33°E, 01 March 1963, Raynal J. 10130 (P,YA); Campo-Ma’an National Park, 2.33°N, 10.5°E, 24 August 2001, van Andel T.R. 4023 (KRIBI,WAG). South-West Region: Menyum (Bakossi), 4.6°N, 9°E, 28 February 1987, Doumenge C. 313 (MO,P,WAG); Mai Idoanu, 4.24°N, 8.99°E, 12 February 1955, Latilo M.G. 34468 (P); Onge River, 4.3°N, 8.95°E, 20 October 1993, Tchouto Mbatchou G.P. 896 (K,YA); Disturbed forest between Liwenyi and big Koto, 4.3°N, 8.95°E, 22 October 1993, Tchouto Mbatchou G.P. 942 (K,YA); Korup National Park, 5.05°N, 8.8°E, 28 February 1984, Thomas D.W. 3242 (MO,YA); Korup National Park, 4.98°N, 8.85°E, 12 January 1979, Thomas D.W. 595 (K). West Region: Baleng, 5.53°N, 10.38°E, 10 May 1964, de Wilde W.J.J.O 2565 (WAG).

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 153. Xylopia thomsonii A base of leaf blade, upper side B base of leaf blade, lower side C fruit. Xylopia villosa (cf, young sterile individual) D leaf, upper side E base of leaf blade, upper side F base of leaf blade, lower side A-C Couvreur. 520, Gabon D, E Couvreur 1227, Masea, Cameroon. Photos Thomas L. P. Couvreur.