Phenax
Content
Description
Subshrubs, monoecious, without stinging hairs. Leaves alternate, distichous; stipules free; blade pinnately veined. Inflorescences bisexual, sessile, subcapitate glomerules with (sub)sessile flowers. Staminate flowers with 4, connate tepals; stamens 4. Pistillate flowers without perianth; stigma filiform, persistent. Fruit an achene.
Distribution
Guianas present, Neotropical present
Neotropical, 10-15 species; in the Guianas one species.
Wood
Growth rings faint or absent. Vessels diffuse, solitary and in radial multiples of 2-4, round to oval, 15-25 per sq. mm, diameter 70-100 μm. Vessel-member length: 240-450 μm. Perforations simple. Intervascular pits alternate, polygonal, 6-10 μm. Vessel-ray and vessel-parenchyma pits as the intervascular pits. Thin-walled tyloses present or absent.
Rays uniseriate (occasionally present) and 2-3 seriate (15-30 μm) wide, 5-6 per mm, up to several mm high. Heterogeneous, composed of square and upright cells. Druses sometimes present.
Parenchyma scarce, paratracheal, vasicentric. Strands of 2-4 cells.
Fibres non-septate, lumen 15-30 μm, walls 3-5 μm. Pits simple, on radial and tangential walls. Length: 665-1745 μm.
Rays uniseriate (occasionally present) and 2-3 seriate (15-30 μm) wide, 5-6 per mm, up to several mm high. Heterogeneous, composed of square and upright cells. Druses sometimes present.
Parenchyma scarce, paratracheal, vasicentric. Strands of 2-4 cells.
Fibres non-septate, lumen 15-30 μm, walls 3-5 μm. Pits simple, on radial and tangential walls. Length: 665-1745 μm.