Couratari macrosperma A. C. Sm.

Trees, to 50 m tall, the trunk buttressed, often low and thick, sometimes to 4 m. Bark with shallow, vertically oriented fissures. Stems puberulous when young, soon becoming glabrous with age. Leaves: petiole 5-9 mm long, tomentellous to glabrescent, canaliculate, markedly winged; blades oblong to oblong-Ianceolate, 8.5-17.5 x 2.5-7.5 cm, with longitudinally oriented parallel striations most common along striations, chartaceous, pubescent abaxially, with two types of shortly stalked stellate hairs, the larger type sparse, 29 times larger than smaller type, the smaller type dense, especially on newly flushed leaves, more common along striations, the base cuneate, the margins entire but slightly undulate, very sparsely ciliate when young, the apex acute to shortly acuminate; midrib prominulous and glabrous adaxially, prominent, with a few scattered appressed hairs abaxially, the secondary veins in 21-27 pairs, prominulous on both surfaces, the tertiary venation slightly prominulous. Inflorescences terminal or axillary, racemes 10-30 cm long, the rachis stellate-tomentellous; pedicels tomentellous, articulate, 2-6 mm long below articulation and 1-4 mm long above articulation. Flowers: hypanthium campanulate, 5-8 mm long; calyx lobes oblong-rounded, ca. 8 mm long, tomentellous on both surfaces, the margins ciliate; petals obovate, ca. 2 cm long, puberulous abaxially, almost glabrous adaxially, white, the apex apex; androecium ca. 3.5 cm long, the staminal ring ca. 15 mm diam., the stamens inserted evenly around ring, the exterior of hood with numerous echinate appendages, white to yellowish; ovary 3(4)-locular. Fruits cylindrical, rounded in cross section, broadest at about middle or at calycine ring, 12-15 x 7 cm, the pericarp crustaceous on exterior, ca. 4 mm thick, hard and woody, the calycine ring 3-15 mm below apex, the sepals prominent, forming distinct 6-partite ridge around calycine ring, the operculum not radially grooved, centrally concave or convex, the columella markedly triangular and longitudinally striate, the pericarp 8-10 mm thick. Seeds oblong-lanceolate, symmetrical, 8-10 x 3 cm, notched at micropylar end, rounded to truncate at distal end.