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Nomenclature etc. THYMELAEACEAE (GONYSTYLACEAE). G. bancanus (Miq.) Kurz (syn.: G. miquelianus Teijsm. & Binn., Aquillaria bancana Miq.); G. macrophyllus (Miq.) Airy-Shaw; G. warburgianus Gilg. Trade and local names: ahmin, kaya garu, melawis, ramin telur (MY); lanutanbagio (PH); garu buaja (ID). Listed in CITES Annex II.
Tree. Geographic distribution: Indomalesia.
General. Heartwood basically yellow to white or grey. Sapwood colour similar to heartwood colour. Odour distinct (green or re-moistened wood often with unpleasant odor), or indistinct or absent. Density 0.55–0.57–0.63 g/cm³.
Vessels. Wood diffuse porous. Vessels in multiples, commonly in short (2–3 vessels) radial rows. Average tangential vessel diameter 85–150–200 µm. Average number of vessels/mm² 9–10–14. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 3–5 µm. Vessel-ray pits with distinct borders, similar to intervessel pits. Other deposits present (few, the colour of amber).
Tracheids and fibres. Fibres of medium wall thickness. Average fibre length 1050–1350–1750 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered or distinctly bordered.
Axial parenchyma. Axial parenchyma not banded. Axial parenchyma paratracheal. Paratracheal axial parenchyma aliform, or confluent, or unilateral. Aliform parenchyma of the winged type. Axial parenchyma as strands. Average number of cells per strand: 2–4–6.
Rays. Rays 9–14 per tangential mm, exclusively uniseriate. Rays composed of a single cell type (homocellular); homocellular ray cells procumbent.
Storied structures. Storied structure absent.
Mineral inclusions. Crystals present, prismatic, located in ray cells. Crystal-containing ray cells procumbent. Number of crystals per cell or chamber one, or more than one. Crystals in one cell or chamber of the same size, or of two distinct sizes. Silica not observed.
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 positive. Splinter burns to partial ash (producing heavy smoke). Ash white to grey.
Illustrations. • Macroscopic images. transverse (ca. 10x). tangential (natural size). • Transverse section. Gonystylus macrophyllus. • Tangential section. Gonystylus bancanus. • Radial section. Gonystylus bancanus. • Crystals; fibre pits. Gonystylus macrophyllus. prismatic crystals in rays. conspicuous fibre pits in radial walls. Gonystylus bancanus.
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’.
