Monodora Dunal, Monogr. Anon. 3: 79, 1817

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 : 246-247

Monodora Dunal, Monogr. Anon. 3: 79, 1817

Type species.

Monodora myristica (Gaertner) Dunal.

Description.

Trees, rarely shrubs or rarely lianas, 4-40 m tall, d.b.h. 6-100 cm; stilt roots or buttresses absent. Indumentum of simple hairs, or absent. Leaves: petiole 2-14 mm long, 1-2 mm in diameter, blade inserted on the side of the petiole; blade 4-50 cm long, 2-15 cm wide, elliptic or obovate or oblong or ovate, apex acuminate, acumen ca. 1 cm long; base cuneate to rounded, concolorous; midrib raised above; secondary veins 8 to 23 pairs; tertiary venation reticulate. Individuals bisexual; inflorescences ramiflorous on old or young foliate branches, leaf opposed or extra axillary, 1 per inflorescence; pedicel 8-270 mm long, 1-2 mm in diameter; in fruit 25-350 mm long, 3-15 mm in diameter; bract 1, towards the upper half or middle of pedicel; sepals 3, valvate, free, 2-40 mm long, 2-17 mm wide, ovate or elliptic, apex acute or attenuate or rounded, base truncate, margins flat, undulate, wavy or crisped; petals basally fused, tube 2-8 mm long, inner and outer whorl differentiated, outer petals longer than inner; outer petals 3, 17-105 mm long, 6-40 mm wide, oblong or obovate or ovate, apex truncate, base truncate or with two small lobes, margins flat or wavy or crisped; inner petals 3, valvate, 9-35 mm long, 5-30 mm wide, cordate or rhombic or triangular to cochleate, apex acuminate to acute, base narrowed into a claw, claw 1-9 mm long; receptacle flat to strongly convex; stamens numerous, in 9 to 20 rows, 1-2 mm long, broad; connective discoid or elongated; staminodes absent; carpels fused into a syncarpous ovary, 1-5 mm long, stigma bilobed, slightly capitate. Fruit syncarpous, sessile, 35-150 mm long, 20-150 mm in diameter, globose or ovoid or conical, apex apiculate to rounded; seeds numerous, 9-22 mm long, 5-13 mm in diameter, ellipsoid or flattened ellipsoid; aril absent.

A genus of trees with 14 known species, from West, Central and East Africa. In Cameroon six species are known, one endemic.

Monodora , together with its sister genus Isolona , are unique in Annonaceae in having truly syncarpous ovaries, producing single fruits with unordered seeds, in contrast to other genera which have either uni- or biseriate placentation. Petals in Monodora are basally fused forming a short (not clearly visible) tube. The petals, however, are differentiated into inner and outer whorls, in contrast to Isolona (which has six equal lobes in a single whorl with a visible tube). In the vegetative state, Monodora and Isolona (together with Polyceratocarpous pellegrinii ) are characterized by a raised leaf midrib on the upper side, in contrast to a sunken or flat midrib in all other genera found in Cameroon. Monodora species tend to have a whitish-grey wax indumentum on young leaves and fruits, which is especially noticeable in the common and widespread species M. myristica .

Taxonomy.

Couvreur (2009).