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Nomenclature etc. FABACEAE-FABOIDEAE. Incl. Alexa imperatricis (Schomb.) Baker, A. leiopetala Sandwith, A. wachenheimii R. Ben., A. bauhiniaeflora Ducke. Trade and local names: sucupira pepino (BR); haiariballi (GY); nekoe-oedoe (SR). Not protected under CITES regulations.
Tree. Geographic distribution: tropical South America.
General. Growth ring boundaries distinct (demarcated by marginal parenchyma bands). Heartwood basically brown and yellow, white or grey. Sapwood colour similar to heartwood colour. Odour indistinct or absent. Density 0.55–0.65 g/cm³.
Vessels. Vessels present. Wood diffuse porous. Vessels arranged in no specific pattern, in multiples, commonly in short (2–3 vessels) radial rows or in radial rows of 4 or more. Average tangential vessel diameter 130–220(–270) µm. Average number of vessels/mm² 1–3. Average vessel element length 310–430–570 µm. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 5–7 µm, pits vestured. Vessel-ray pits with distinct borders, similar to intervessel pits. Helical thickenings absent. Tyloses absent. Other deposits present (light amber).
Tracheids and fibres. Fibres of medium wall thickness. Average fibre length 1000–1650–2150 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Fibres non-septate.
Axial parenchyma. Axial parenchyma banded. Bands marginal (or seemingly marginal). Bands fine. Apotracheal axial parenchyma diffuse-in-aggregates. Paratracheal axial parenchyma aliform and confluent. Aliform parenchyma of the lozenge type. Axial parenchyma as strands. Average number of cells per strand: 3–5.
Rays. Rays 6–10 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.
Storied structures. Storied structure absent.
Secretory structures. Intercellular canals absent. Laticifers or tanniniferous tubes absent.
Cambial variants. Included phloem absent.
Mineral inclusions. Crystals present, prismatic, located in axial parenchyma cells. Crystal-containing axial parenchyma cells chambered. Number of crystals per cell or chamber one. Silica not observed.
Illustrations. • Transverse section. Alexa imperatricis. • Tangential section. Alexa imperatricis. • Radial section. Alexa imperatricis.
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’.
