Commercial Timbers


H. G. Richter and M. J. Dallwitz

Chrysophyllum gonocarpum (Martius & Eichler)Engler (Aguai)

Nomenclature etc. SAPOTACEAE. Syn.:Sapota gonocarpa Martius & Eichler, Chrysophyllum cysneiri F. Allemão, Chrysophyllum cearaenses F. Allemão, Chrysophyllum obtusifolium F. Allemão, Chrysophyllum persicastrum Eichler, Chrysophyllum lucumifolium Grisebach, Martiusella gonocarpa (Martius & Eichler)Pierre, Sideroxylon reticulatum Britton, Chrysophyllum lucumifolium f. obtusata Chodat & Hassler, Sideroxylon bolivianum Rusby, Pouteria boliviana (Rusby) Baehni, Chloroluma gonocarpa (Martius & Eichler) Baillon ex Aubréville. Not protected under CITES regulations.

Description based on 2 specimens. Tree. Geographic distribution: southern Brazil.

General. Growth ring boundaries distinct and indistinct or absent. Growth ring limits, if distinct, demarcated by a band of thicker walled fibres and by low concentration of axial parenchyma.

Vessels. Vessels present. Wood diffuse-porous. Vessels arranged in diagonal and/or radial pattern, in multiples, commonly short (2–3 vessels) radial rows and radial rows of 4 or more. Vessel outline rounded. Two distinct vessel diameter classes absent. Average tangential vessel diameter 30–60–85 µm; diameter of vessel lumina: medium. Average number of vessels/mm² 35–38–44; vessels per square millimetre moderately numerous. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 5–8 µm, small and medium, not vestured. Vessel-ray pits with reduced borders or apparently simple, different from intervessel pits, rounded or angular and horizontal to vertical, of two distinct sizes or types in the same ray cell, of the same type in adjacent elements, located throughout the ray. Helical thickenings absent. Tyloses in vessels present, thinwalled. Other deposits in heartwood vessels not observed.

Tracheids and fibres. Vascular or vasicentric tracheids commonly present. Fibres of medium wall thickness. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Helical thickenings absent. Fibres non-septate.

Axial parenchyma. Axial parenchyma present, not banded. Axial parenchyma apotracheal. Apotracheal axial parenchyma diffuse-in-aggregates. Axial parenchyma as strands. Average number of cells per axial parenchyma strand (3–)4–5(–7). Unlignified parenchyma absent.

Rays. Rays present, 11–14–16 per tangential mm, multiseriate (also if only few), (1–)2(–3) cells wide, narrow (2–3 seriate). Rays with multiseriate portions as wide as uniseriate portions present and absent. Aggregate rays absent. Rays of one size. 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, mostly 2–4 marginal rows of upright or square cells, and with more than 4 marginal rows of upright or square cells. Sheath cells absent. Tile cells absent. Perforated ray cells absent. Disjunctive ray parenchyma end walls distinct.

Storied structures. Storied structure absent.

Secretory structures. Oil and mucilage cells absent. Intercellular canals absent.

Cambial variants. Included phloem absent. Other cambial variants absent.

Mineral inclusions. Crystals present, prismatic and in form of crystal sand, located in ray cells and axial parenchyma cells. Crystal-containing ray cells upright and/or square, upright and/or square ray cells chambered and not chambered. Crystals in procumbent ray cells not in radial alignment. Crystal-containing axial parenchyma cells chambered and not chambered. Number of crystals per cell or chamber one and more than one. Crystals in one cell or chamber of the same size and of two distinct sizes. Crystal containing cells of normal size. Cystoliths absent. Silica not observed.

Illustrations. • Transverse section. Chrysophyllum gonocarpum. • Tangential section. Chrysophyllum gonocarpum. • Radial section. Chrysophyllum gonocarpum.

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: 25th June 2009.’.