Uvariastrum pierreanum Engl., Monogr. Afrik. Pflanzen.-Fam. 6: 32, 1901

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 : 377-379

Uvariastrum pierreanum Engl., Monogr. Afrik. Pflanzen.-Fam. 6: 32, 1901

Figs 117 , 118 ; Map 14I

Type.

Gabon. Estuaire; Libreville, Klaine T.-J. 1091, Oct 1897: lectotype, designated by Le Thomas (1969b), p. 294: P[P00315822]; isolectotype: B[B1001153112] .

Description.

Tree to shrub, 4-25 m tall, d.b.h. 40 cm; stilt roots or buttresses absent. Indumentum of simple hairs; old leafless branches glabrous, young foliate branches sparsely pubescent. Leaves: petiole 2-4 mm long, 1-2 mm in diameter, sparsely pubescent to glabrous, weakly grooved adaxially, blade inserted on the side; blade 6-16 cm long, 2-4.5 cm wide, elliptic to obovate, apex acuminate, acumen 0.7-2 cm long, base decurrent to cuneate, papyraceous to subcoriaceous, below sparsely pubescent to glabrous when young, sparsely pubescent to glabrous when old, above sparsely pubescent to glabrous when young, sparsely pubescent to glabrous when old, concolorous; midrib sunken or flat, above glabrous when young and old, below glabrous when young and old; secondary veins 7 to 12 pairs, glabrous above; tertiary venation reticulate. Individuals bisexual; inflorescences cauliflorous or ramiflorous on young foliate or old leafless branches, axillary. Flowers with 9 perianth parts in 3 whorls, 1 to 3 per inflorescence; pedicel 15-50 mm long, 1-2 mm in diameter, sparsely pubescent to densely pubescent; in fruit 15-50 mm long, 4-6 mm in diameter, sparsely pubescent to glabrous; bract 1, basal, 6 mm long, 6 mm wide; sepals 3, reduplicate-valvate, free, 15-25 mm long, 10-20 mm wide, ovate, apex acute, base truncate, grey-green, pubescent towards margins outside, sparsely pubescent inside, margins revolute; petals free, sub equal; outer petals 3, 25-40 mm long, 10-15 mm wide, elliptic, apex acute, base narrowed, yellow to greyish yellow, margins flat, densely pubescent outside, sparsely pubescent inside; inner petals 3, valvate, 15-28 mm long, 6-15 mm wide, elliptic, apex acute, base cuneate, yellow to greyish yellow, margins flat, densely pubescent outside, sparsely pubescent inside; stamens numerous, 4-6 mm long, linear; connective elongated, pubescent, pinkish red; staminodes absent; carpels free, 5 to 10, ovary 4-6 mm long, stigma bilobed, slightly capitate, densely pubescent. Monocarps shortly stipitate to sessile, stipes 0-4 mm long, 3-5 mm in diameter; monocarps 3 to 5, 90-100 mm long, 40-50 mm in diameter, ellipsoid to globose, apex rounded, pubescent, velvety, smooth, not ribbed, light green when ripe; seed 16 to 20 per monocarp, 15-25 mm long, 1-2 mm in diameter, flattened ellipsoid; aril absent.

Distribution.

A widespread species with a disjunct distribution in west and central Africa, from Guinea and Liberia to Ghana, and from Nigeria to Republic of Congo, and northern Democratic Republic of Congo. In Cameroon known from the East, South, Central and South-West regions.

Habitat.

A fairly common species; in primary or secondary lowland rain forest or in gallery forests near savannas, on non-inundated soils or along rivers, occurring on sandy or rocky soils. Altitude 0-600 m a.s.l.

Local and common names known in Cameroon.

None recorded.

IUCN conservation status.

Least Concern (LC) ( Cosiaux et al. 2019a u).

Uses in Cameroon.

None reported.

Notes.

Uvariastrum pierreanum is characterized by a combination of light brown sepals and glabrous leaves and smooth monocarps. By the shape of its flowers and glabrous aspect, U. pierreanum resembles U. zenkeri , but the latter has large leathery leaves and its leaf blade is inserted on top instead of on the side of the petiole. In herbarium material, the sepals of U. pierreanum dry brown, whereas those of U. zenkeri dry black.

Specimens examined.

Central Region: Mefou National Park , 3.61°N, 11.58°E, 13 March 2004, Cheek M. 86 (K,YA). East Region : 3 km west of Djembe road head Lobeke Reserve , 2.21°N, 16°E, 16 October 1998, Harris D.J. 5889 (E); Lobeke Reserve Small Bai , 2.28°N, 15.71°E, 01 November 1998, Harris D.J. 6135 (E); A 25 km à l’WSW de Kinsassa village situé à 65 km au NNE de Moloundou sur route de Yokadouma 2.56°N, 15.16°E, 09 March 1971, Letouzey R. 10533 (HGB,P,YA); Foret au Sud de Dimako rive droite de la rivière Mbonda , 4.26°N, 13.56°E, 18 January 1960, Letouzey R. 2670 (P,YA); A 13 km SSW de Koso (village situé à 60 km au SSW de Batouri), 3.93°N, 14.17°E, 29 July 1963, Letouzey R. 5529 (P,YA); Approximately 10 km N of Welele between Yokadouma and Molundu, 2.68°N, 15.36°E, 18 March 1987, Manning D. 1586 (MO,P,YA); Reserve de Biosphere du Dja vers 1175 m sur la piste reliant la station de Bouamir et l’inselberg de Mbasakok, 3.18°N, 12.81°E, 18 May 2001, Senterre B. 1283 (BR); Reserve de Biosphere du Dja vers 1175 m sur la piste reliant la station de Bouamir et l’inselberg de Mbasakok, 3.18°N, 12.81°E, 19 May 2001, Senterre B. 1370 (BR). South Region : Bitye, 3.01°N, 12.35°E, 01 September 1922, Bates G.L. 1764 (K); Campo Ma an National Park 5 km after main entrance, 2.35°N, 10.25°E, 15 February 2012, Couvreur T.L.P. 385 (WAG,YA); 1 km from main camp near Lele river 16 km East from Lele village , 2.28°N, 13.32°E, 07 September 2013, Couvreur T.L.P. 454 (WAG,YA); Campo Ma'an National Park 11 km on trail from Ebinanemeyong village on road 7 km from Nyabessan to Campo town, 2.49°N, 10.34°E, 12 February 2015, Couvreur T.L.P. 680 (WAG,YA); Ca 30 km S of Mbalmayo, 3.29°N, 11.44°E, 13 February 1964, de Wilde J.J.F.E 1904 (B,BR,K,MO,P,WAG,YA); Station de cacaoyer de N’koemvone 14 km On the road from Ebolowa to Ambam, 2.81°N, 11.13°E, 18 February 1975, de Wilde J.J.F.E 7972 (B,BR,K,MO,P,U,WAG,YA); Meyo Centre, 2.55°N, 11.03°E, 24 March 1970, Letouzey R. 10225 (P) .

Figures

Map 14. A Uvaria klaineana B Uvaria mollis C Uvaria muricata var. yalingensis D Uvaria obanensis E Uvaria osmantha F Uvaria poggei G Uvaria scabrida H Uvariastrum insculptum I Uvariastrum pierreanum. White borders represent region limits in Cameroon; green patches represent protected areas (see methods and Suppl. material 1: Fig. S 1).

Figure 117. Uvariastrum pierreanum A flowering branch B flower, cauliflorous C outer petals, inner and outer view D longitudinal section of receptacle E stamen, front view F carpel, front and side view, and detail of ovules G fruit. Uvariastrum insculptum H flowering branch I flower bud, note reflexed sepal margins J outer petals, inner and outer view K stamen, front view L carpel, front view and detail of ovules M detail of monocarp, and N longitudinal section of monocarp showing seeds A, B from Letouzey 2670 C-G from Le Testu 6083 H from Klaine 99 I, J, N from Staudt 740 K-M from Aubreville 1331. Drawings by Helene Lamourdedieu, Publications Scientifiques du Museum national d'Histoire naturelle, Paris; modified from Le Thomas (1969 b, pl. 53, p. 293).

Figure 118. Uvariastrum pierreanum A habit B flower, side view, one outer and one inner petal removed C flower, side view D flower bud, note folded sepal margins J young fruits. Uvariastrum zenkeri F habit, U. zenkeri is the smaller tree, note yellow flowers E flower, top view G base of leaf blades, lower side H base of leaf blade, upper side, note leaf blade inserted on top of the petiole I fruit A-D Couvreur 454, Lele, Cameroon E, G, H Couvreur 624, Ebo, Cameroon F Couvreur 877, Gabon I Couvreur 572, Gabon J Couvreur 590, Gabon. Photos Thomas L. P. Couvreur.