Glabrous tree, 7-10 m tall. Stipules +/- deltoid, less than 1 mm long, +/- entire; petioles 5-10 mm long, narrowly winged; blades elliptic to oblong-elliptic, abruptly acuminate, attenuate and decurrent at base, 6-12 cm long, 3-5.5 cm wide, moderately thick, drying gray-green, the acumen obtuse, the margins entire and weakly revolute. Racemes very short, condensed; pedicels 2-6 mm long, articulate at base; flowers functionally unisexual, solitary, appearing before or with new leaves; calyx ca 3 mm wide, weakly 5-lobed, the lobes irregular; petals 4 or 5, ovate, rounded at apex, ca 2 mm long and 1.6 mm wide, imbricate in bud, spreading at anthesis, cream to yellowish; stamens 4 or 5, inserted below the broad, flattened disk, ca 1.5 mm long; filaments broadest and +/- flattened at base; anthers introrse; ovary embedded in disk and confluent with it, 2-4-locular; stigma +/- sessile, 2-4-lobed. Capsules usually few, often apparently paired, obovate, ca 1.5 cm long, smooth, orange; valves usually 2, coriaceous, opening broadly to expose seeds; seeds usually 2, arillate, the aril white, about as long as seed. Croat 6135, Hayden 144. The pollination system is unknown. The arillate seeds are well suited for bird dispersal. The Flora of Panama treatment by Edwin and Hou (1975) included Hayden 144 under M. guyanensis Klotzsch & Schomb. However, that collection differs in no important way from other BCI material included under M. schippii, and I believe it was collected from the same tree as Croat 6135. Stern et al. 863 from Darien is also M. schippii.