Aptandra
Description
Glabrous shrubs or trees. Leaves micropunctate against strong light. Inflorescences axillary pedunculate slender panicles. Flowers small; calyx patelliform, deeply 4-dentate, small at anthesis but very much enlarged in fruiting stage; petals 4, linear-ligulate, free; disc-glands 4, petaloid, alternating with the petals; stamens 4, filaments connate to a cylindrical tube, anthers oblong, the thickish connectives concrescent to an annulus; ovary substipitate, 2-sulcate,2-locular below, with 2 ovules; style slender, clavate, as long as the staminal tube, stigma obtuse. A single drupe per infructescence, included in its lower half by the much enlarged calyx, pericarp coriaceous; endocarp woody, endosperm fleshy, containing amylum and fatty substances, with a small embryo at its apex, cotyledon orbicular, foliaceous.
Distribution
Amazonian South America present, Guianas present, tropical West Africa present
3 species, 1 in tropical West Africa and 2 in Amazonian South America, 1 of these in the Guianas.
Wood
Vessels diffuse, solitary (25-76%) and in radial multiples of 2-4, round, oval or angular, 6-37 per sq. mm, diameter 92-124 μm. Vessel-member length: 417-766 μm. Perforations simple. Intervascular pits alternate, round to polygonal, 4-7 μm. Vessel-ray and vessel-parenchyma pits of two types: half-bordered diffuse to alternate (similar in shape and size to intervascular pits) and large and simple. Thin-walled tyloses infrequently present. Vascular tracheids associated with vessel multiples, sometimes integrating with narrow vessel elements, scarce to abundant.
Rays of Kribs' heterogeneous type II to III, predominantly uni- or bi-seriate, 8-9 per mm, up to 824 μm high. Perforated ray cells infrequently present.
Parenchyma scanty to abundant, apotracheal and paratracheal, diffuse or in small aggregates, in strands of 3-5 cells.
Ground tissue composed of very thick-walled fibre-tracheids, lumen 16-23 μm. Pits bordered in both radial and tangential walls, diameter of borders 3-6 μm. Length: 1171-2214 μm.
Crystals solitary rhomboidal, in chambered ray and axial parenchyma cells, absent in some specimens.
Rays of Kribs' heterogeneous type II to III, predominantly uni- or bi-seriate, 8-9 per mm, up to 824 μm high. Perforated ray cells infrequently present.
Parenchyma scanty to abundant, apotracheal and paratracheal, diffuse or in small aggregates, in strands of 3-5 cells.
Ground tissue composed of very thick-walled fibre-tracheids, lumen 16-23 μm. Pits bordered in both radial and tangential walls, diameter of borders 3-6 μm. Length: 1171-2214 μm.
Crystals solitary rhomboidal, in chambered ray and axial parenchyma cells, absent in some specimens.