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| Commercial timbers |
Nomenclature etc. MORACEAE. Incl. Antiaris africana Engl., A. toxicaria Lesch, A. welwitschii Engl. Trade and local names: Africa: ako (CI, SN); antiaris (GB); akede (CI); bonkonko (CD); chenchen (GH); kirundu (eAfr); mongodou, false oro (NG); vawi, diolosso (CM); Asia: ipoh, upas (ID, MY). Not protected under CITES regulations.
Tree. Geographic distribution: Myanmar (Burma), Thailand, Laos, Vietnam, Cambodia, Indomalesia (only A. toxicaria), tropical Africa (A. africana, A. toxicaria, A. welwitschii).
General. Growth ring boundaries indistinct or absent. Heartwood basically yellow, white or grey. Sapwood colour similar to heartwood colour. Density 0.4–0.45–0.5 g/cm³. Ribbon figure due to interlocked grain.
Vessels. Wood diffuse porous. Vessels in multiples, commonly in short (2–3 vessels) radial rows. Occasionally radial vessel groups of 4 and small clusters. Average tangential vessel diameter 155–200–245 µm. Vessels per square millimetre very few, or few. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 8–10 µm. Vessel-ray pits with reduced borders or apparently simple, rounded or angular to horizontal to vertical, of uniform size or type, of the same type in adjacent elements. Tyloses present, thinwalled. Vessel lines often appearing dark due to blue stain.
Tracheids and fibres. Fibres very thin-walled, or of medium wall thickness (quite rare). Average fibre length 640–1050–1375 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Fibres exclusively septate; evenly distributed.
Axial parenchyma. Axial parenchyma present. Apotracheal axial parenchyma diffuse-in-aggregates. Paratracheal axial parenchyma vasicentric, or aliform to confluent (less frequently). Aliform parenchyma of the lozenge type. Axial parenchyma as strands. Average number of cells per strand: 2–4(–8).
Rays. Rays multiseriate, (1–)3–6 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 to mostly 2–4 marginal rows of upright or square cells.
Storied structures. Storied structure absent.
Secretory structures. Intercellular canals absent. Laticifers or tanniniferous tubes present (latex tubes).
Mineral inclusions. Crystals present, prismatic or in other forms (small, mostly circular crytals), located in ray cells or axial parenchyma cells or fibres (reported only for A. toxicaria by Janssonius). Crystal-containing ray cells upright and/or square and procumbent. Crystal-containing axial parenchyma cells not chambered. 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. Splinter burns to partial ash. Ash white to grey.
Illustrations. • Macroscopic images. transverse (ca. 10x). radial (natural size). • Transverse section. Antiaris africana. • Tangential section. Antiaris africana. latex tubes in rays (Lt). Lt. • Radial section. Antiaris africana.
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’.
