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| Commercial timbers |
Nomenclature etc. FABACEAE-CAESALPINIOIDEAE. Trade and local names: zandlocus, kabakally, singapetou (SR), angélica do Para, tapaiuna (BR); "tec" de la Guayane (FR), Guayana "Teak" (trade). Not protected under CITES regulations.
Tree. Geographic distribution: tropical South America.
General. Heartwood basically brown. Sapwood colour distinct from heartwood colour. Density 0.6–0.72 g/cm³. With interlocked grain.
Vessels. Wood diffuse porous. Vessels in multiples, commonly in short (2–3 vessels) radial rows (occasionally with some longer radial chains and small clusters). Average tangential vessel diameter 185–245–295 µm. Average number of vessels/mm² 2–5. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 5–7 µm, pits vestured. Vessel-ray pits with distinct borders, similar to intervessel pits. Tyloses absent. Other deposits present (light to dark reddish brown).
Tracheids and fibres. Fibres of medium wall thickness. Average fibre length 1230–1625–2040 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Fibres non-septate. Fibres often with dark coloured contents.
Axial parenchyma. Axial parenchyma banded and not banded. Bands marginal (or seemingly marginal) or not marginal (or seemingly marginal). Axial parenchyma bands much wider than rays. Bands fine or coarse. Axial parenchyma apotracheal, or paratracheal. Apotracheal axial parenchyma rarely diffuse-in-aggregates. Paratracheal axial parenchyma vasicentric, aliform, confluent, and unilateral (predominantly aliform confluent). Aliform parenchyma of the winged type. Axial parenchyma as strands. Average number of cells per strand: (2–)4–8(–10).
Rays. Rays 6–12 per tangential mm, multiseriate, 1–2–3 cells wide. Height of large rays up to 500 µm. Rays composed of two or more cell types (heterocellular). Heterocellular rays with square and upright cells restricted to marginal rows, mostly 1 marginal row of upright or square cells (rarely 2 rows). Sheath cells absent.
Storied structures. Storied structure present (not always distinct), all rays storied, axial parenchyma storied, vessel elements storied, fibres not storied. Arrangement of tiers regular. Number of ray tiers per axial millimetre 2. Storied strata often slightly inclined.
Secretory structures. Intercellular canals absent.
Mineral inclusions. Crystals not observed. Silica present, as grains; in rays cells and in axial parenchyma.
Physical and chemical tests. Heartwood not fluorescent. Water extract not fluorescent; colour of water extract colourless to brown. Ethanol extract not fluorescent. Colour of ethanol extract colourless to brown. Froth test negative. Splinter burns to charcoal.
Illustrations. • Macroscopic images. transverse (ca. 10x). radial (natural size). Dicorynia guianensis. • Transverse section. Dicorynia guianensis. • Tangential section. Dicorynia guianensis. • Radial section. Dicorynia guianensis. • Silica. silica particles in axial parenchyma (Ap) and rays (Hs). Ap. Ap. Hs. Hs. Hs. Ap.
The interactive key allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting specified attributes, summaries of attributes within groups of taxa, and geographical distribution.
Cite this publication as: ‘Richter, H.G., and Dallwitz, M.J. 2000 onwards. Commercial timbers: descriptions, illustrations, identification, and information retrieval. In English, French, German, Portuguese, and Spanish. Version: 9th April 2019. delta-intkey.com’.
