Uvariastrum Engl., Monogr. Afrik. Pflanzen.-Fam. 6: 31, 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 : 374

Uvariastrum Engl., Monogr. Afrik. Pflanzen.-Fam. 6: 31, 1901

Type species.

Uvariastrum pierreanum Engl. & Diels.

Description.

Trees or shrubs, 4-30 m tall, d.b.h. up to 30 cm; stilt roots or buttresses absent. Indumentum of simple hairs. Leaves: petiole 1-4 mm long, 1-2 mm in diameter; blade 6-22 cm long, 2-5 cm wide, elliptic or obovate, apex acuminate, acumen 0.7-2 cm long, base subcordate to decurrent to rounded to cuneate, concolorous; midrib sunken or flat; secondary veins 7 to 17 pairs, arching well before the margin; tertiary venation reticulate. Individuals bisexual; inflorescences cauliflorous, or ramiflorous young foliate branches and axillary. Flowers with 9 perianth parts in 3 whorls, 1 to 3 per inflorescence; pedicel 8-50 mm long; in fruit 10-50 mm long; bracts 1 to 3, all basal; sepals 3, reduplicate-valvate, free, 10-25 mm long, apex acute, base truncate; petals free, sub equal; outer petals 3, valvate, 20-40 mm long, 5-15 mm wide, ovate to elliptic, apex acute, base truncate or narrowed; inner petals 3, valvate, 10-28 mm long, 6-15 mm wide, ovate or elliptic, apex acute, base cuneate; stamens numerous (not counted), 2-6 mm long, linear; connective elongated to discoid; staminodes absent; carpels free, 5 to 16, 2-6 mm long, stigma bilobed or capitate. Monocarps stipitate or sessile, stipes 1-6 mm long; monocarps 2 to 8, 30-100 mm long, 10-50 mm in diameter, globose or ellipsoid, apex apiculate or acute to rounded; seeds 16 to 27, 10-25 mm long, 7-15 mm in diameter, flattened ellipsoid; aril absent.

A genus of five species from West and Central Africa; one species adapted to the drier regions in southern Central Africa ( U. hexaloboides (R.E.Fr.) R.E.Fr.); in Cameroon three species, none endemic.

Taxonomy.

Couvreur (2014).