Mwasumbia Couvreur & D.M.Johnson

Tree 2-3 m tall, DBH 3-5 cm. Twigs slender, longitudinally striate, densely covered with erect hairs 1.0-1.3 mm long, soon glabrate, brown. Leaf blades 7-14 cm long, 3-6 cm wide, length:width ratio 1.9-2.6, obovate or rarely elliptic, obliquely broadly cuneate to subcordate at base, acuminate to cuspidate at the apex, the acumen 5-22 mm long; midrib slightly impressed and glabrous above, raised and sparsely covered with appressed hairs to glabrous below; secondary veins 8-10 per side, diverging at 45-60° from midrib, slightly impressed to slightly raised above, slightly raised below, higher-order veins irregular, plane to slightly raised above, slightly raised below; petiole 1-2.5 mm long, 0.8-1 mm in diameter, covered with short erect hairs to glabrous, leaf lamina inserted on top. Inflorescences axillary, sometimes cauliflorous, a 1-flowered rhipidium. Buds not enclosed in sepals, ovoid to conic, densely covered with short appressed hairs, white to white-cream. Sympodial rachis to 7 mm long, densely covered with short appressed hairs, brown, with 0-6 minute lower bracts which are densely covered with short appressed hairs and brown. Flowering pedicels 10-22 mm long, densely covered with short appressed hairs, green, upper bract inserted at 1/3 from the base, minute, appressed against pedicel, covered with short appressed hairs, green. Flowers bisexual, with two whorls of 3 free petals. Sepals 3, free, slightly imbricate at base, 4-3 mm long, 4-5 mm wide, length:width ratio 0.75-0.8, broadly ovate, base subcordate, apex acute, densely covered with short appressed hairs outside, glabrous inside, appressed against petals, persistent in fruit. Petals white to white-cream in vivo, drying dark black; outer petals 12-18 mm long, 10-7.5 mm wide, length:width ratio 1.8-2.1, elliptic, base truncate, apex obtuse; sericeous outside, glabrous inside except for fine puberulence towards apex and along margins, flat, spreading horizontally at anthesis; inner petals 13-18 mm long, 5-6 mm wide, length:width ratio 2.6-3, narrowly oblong, base truncate, apex acute, glabrous on both sides, the margins with short appressed hairs, concave and erect at anthesis. Stamens in 6-8 whorls, 2-2.7 mm long, filament < 0.2 mm long, narrowed, apical prolongation of connective flat, c. 2 mm long, glabrous, white cream. Torus c. 1.8-2.2 mm long, 2-2.8 mm in diameter at apex, short-cylindric. Carpels 4(3?), 2-3 mm long, c. 1 mm wide, oblong, densely covered with appressed hairs; ovules uniseriate, 5-8 in number, placentation lateral; stigmas bilobed, glabrous, bright yellow to white cream. Fruiting pedicels c. 10-15 mm long, covered with short appressed hairs. Monocarps 18-25 mm long, 10-15 mm in diameter, ellipsoid, sessile, densely covered with short dark brown erect hairs in combination with additional sparsely spaced longer light brown hairs. Seeds c. 2 per monocarp, c. 11 mm long, c. 10 mm wide, 4-5 mm thick, spherical and flattened; testa rugose, brown; raphe depressed; hilum c. 4 mm long, 2 mm wide, elliptic.