Tree to 35-40 m; d.b.h. to 40(-100) cm; crown drooping, bole cylindrical, fissured with some flutes present; bark pale grey; young branches drying black sometimes sparsely spotted with white lenticels, with blue-greyish wax layer; old branches ash-grey to brown. Petioles 8-14 mm long, 1-2 mm in diameter, leaf lamina inserted side, broadly grooved adaxially, sometimes with blue-greyish wax layer. Leaf lamina 11-50 cm long, 4-14 cm wide, length:width ratio 2-3.5, narrowly obovate to obovate or narrowly elliptic to elliptic, base cordate to rounded or rarely cuneate, apex acuminate, acumen 10-15 mm long, membranous to coriaceous, glabrous, green above, pale green below; midrib raised and glabrous adaxially, prominent and glabrous abaxially; secondary veins 13-23 pairs, uniformally curving upwards, glabrous. Flowers single, leaf opposed, pendulous. Flowering pedicels 7-27 cm long, ca. 2 mm in diameter, glabrous, light green stained with dark purple patched, with blue-greyish wax layer. Upper bract inserted central to subapically on the pedicel, 1.5-4 cm long, 0.8-3 cm wide, length:width ratio 2-2.5, elliptic to obovate, base decurrent, apex acute to attenuate, glabrous, green with dark purple streaks; margins undulate, glabrous. Sepals 2-4 cm long, 0.7-1.7 cm wide, length:width 2-2.5, elliptic to ovate, base truncate, apex attenuate, glabrous, pale yellow densely streaked with purple to completely dark red; reflexed upwards, falling when in fruit, margins strongly undulate, glabrous. Inner and outer petals basally fused running down the pedicel for 6-8 mm before reflexing upwards. Outer petals 4-10.5 cm long, 2-4 cm wide, length:width ratio 1.8-3, narrowly ovate to ovate, base truncate, apex acute, glabrous, deep yellow at base streaked with dark red, pale yellow spotted dark purple when younger; arc shaped and dropping, margins strongly undulate, glabrous. Inner petals 25-35 mm long, 25-30 mm wide, length:width ratio 1-1.5, clawed cordate, base cordate, apex acute to obtuse, glabrous, basal lobes of lamina covered with short erect hairs, white with red central vein on the outside, white and specked with red-yellow on the inside; margins straight, covered with short curly hairs, connivent over receptacle; claw 2-5 mm long, 6-8 mm wide, claw:inner petal ratio 0.08-0.15, glabrous, yellow turning dark red. Receptacle 6-9 mm in diameter, strongly convex. Stamens in 16-20 rows, 1.8-2 mm long, connective shield ca. 0.2 mm long, elongated, covered with short erect hairs, those of inner whorl not elongated over ovary wall, white. Ovary partially overtopping stamens, 4-5 mm long, 4-5 mm in diameter, light green at anthesis; stigma ca. 3 mm in diameter, sparsely covered with short erect hairs, yellow-green. Fruiting pedicels to 30-35 cm long, 10-15 mm thick, woody, dark brown, with a clear scar of the bracteole, glabrous. Fruits 9-15 cm long, 8-15 cm in diameter, globose, 2-3 mm in diameter, smooth, finely longitudinally ribbed, lenticellate, green with white dots turning pale yellow when mature; pericarp 1-1.5 cm thick. Seeds 15-22 mm long, 10-13 mm wide, transversely ellipsoid, packed in white pulp; testa light to dark brown with strong scent of lemon; raphe not thinckened, slightly darker brown; hilum 4-6 mm long, 2.5-3 mm wide, narrowly elliptic to narrowly ovate.
Monodora myristica is easily recognizable by its very long and pendulous pedicels, with an undulate upper bract, a large globose fruit with a black and smooth but finely ribbed surface. It bears great similarity to M. undulata by the shape of the flower and the connivance of the inner petals, but is distinguished because it has a shorter pedicel and a straight upper bract and an ovoid fruit with a rough brownish surface. It also resembles M. laurentii by the connivance of the inner petals over the receptacle.
The aromatic seeds have a spicy taste and are used in soup (Burkill 1985), generally as an alternative to nutmeg (Myristica fragrans). Seeds eaten grilled against constipation, gastritis, or squashed and rubbed against forehead against headaches or migraines (Cooper and Record 1931; Burkill 1985; Neuwinger 2000), or can be mixed with palm oil for treating hair lice (Neuwinger 2000). As for M. angolensis, the seeds are sometimes made into necklaces (Cooper and Record 1931). Extracts from the bark have been used against hemorrhoids, stomach pain or fever (Neuwinger 2000). Used in family circles to bless the loved one by spitting the chewed seeds on his head or in his hands. A maceration of the leaves is drunk against measles (Neuwinger 2000). Used in Uganda as firewood or charcoal (Katende et al. 1995). Planted as an ornamental tree throughout the tropics and in botanical gardens.
NT: very widespread through out tropical West and Central Africa
M. laurentii was inferred with moderate support as sister to M. myristica.
Throughout West and Central Africa, east to Uganda and the extreme west of Tanzania and Kenya; in primary and secondary rain forests, along rivers and near marshes, on sandy or rocky soils; at 0-1600 m altitude.