Otoba (Candolle) Karsten (1882: 578).

Myristica sect. Otoba Candolle (1855: 30).

Dialyanthera Warburg (1895: 83).

Type:— Myristica otoba Willdenow (Fig. 1)

Homotypic synonyms: Dialyanthera otoba (Willdenow) Warburg; Otoba novogranatensis Moldenke.

Dioecious trees. Branchlets terete or angular, glabrescent to glabrous or pulverulent. Hairs 2-branched, branches uneven, sessile to 1.5 mm long, usually of two sizes, mainly on the lamina; hyaline crystals often present throughout. Leaves with canaliculate, sometimes with winged petiole; lamina pubescent or glabrescent, entire, membranous or papery to leathery; primary vein raised below; secondary veins irregularly or not anastomosing near margin; tertiary veins inconspicuous; intersecondary veins sometimes present. Inflorescences axillary to foliage leaves or on defoliated nodes, with 1–3(–5) partial inflorescences; each partial inflorescence spicate with sessile umbelliform parts, usually pubescent; bracts ovate, deltoid or reniform, usually inconspicuous when present, caducous; bracteoles absent or rarely present. Perianth 3(–4)-lobed. Staminate flowers with a small perianth, somewhat fleshy, inner perianth surface glabrous, smooth or spongy; stamens 3; filaments fused to a column, occasionally distally divergent, or free almost to the base; anthers longitudinally reniform or globose, free and divergent (fused when immature), or fused at the base; connective inconspicuous. Pistillate flowers usually larger, fleshier or stouter than staminate ones; gynoecium grooved at base; ovary glabrous or pubescent, bottle-shaped, ellipsoidal, obconical, or globose and sometimes stalked; stigma sessile to subsessile, bilobed, elongate. Fruit globose to ellipsoidal, 2-valved, rarely carinate; pericarp usually woody, rugose to striate or smooth; aril white to yellow (-orange), usually thin, laciniate for 1/2 or more of its length; seed ellipsoidal or globose, red-brown.