Myrcianthes pungens (Berg.) Legrand (guaviju)
Nomenclature etc. MYRTACEAE. Status of protection under CITES regulations: not protected.
Description based on: 1 specimen. Tree. Geographic distribution: southern Brazil.
General. Growth ring boundaries indistinct or absent.
Vessels. Vessels present. Wood diffuse-porous. Vessels arranged in no specific pattern, exclusively solitary. Vessel outline rounded. Two distinct vessel diameter classes absent. Average tangential vessel diameter 10–24–42 µm. Average tangential diameter of vessel lumina small. Average number of vessels/mm² 105–137–179. Vessels per square millimetre very numerous. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 5–7 µm (como los vasos son mayormente solitarios, se han medido las punteaduras de las traqueidas vasculares o vasicéntricas), not vestured. Vessel-ray pits with distinct borders, similar to intervessel pits, of uniform size or type, of the same type in adjacent elements, located throughout the ray. Helical thickenings absent. Tyloses in vessels absent. Other deposits in heartwood vessels not observed.
Tracheids and fibres. Vascular or vasicentric tracheids commonly present. Fibres of medium wall thickness. Fibre pits common in both radial and tangential walls, distinctly bordered. Helical thickenings absent. Fibres non-septate.
Axial parenchyma. Axial parenchyma present, banded. Axial parenchyma bands not marginal (or seemingly marginal), bands much wider than rays, fine, up to three cells wide and coarse, more than three cells wide. Axial parenchyma apotracheal. Apotracheal axial parenchyma diffuse and diffuse-in-aggregates. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 3–5. Unlignified parenchyma absent.
Rays. Rays present, 15–18–21 per tangential mm, multiseriate, also if only few, (1–)2(–3) cells wide, 2–3 cells wide. Rays with multiseriate portions as wide as uniseriate portions absent. Aggregate rays absent. Rays of one size. Height of large rays commonly 500 to 1000 µm. Rays composed of two or more cell types. Heterocellular rays square and upright cells restricted to marginal rows. Number of marginal rows of upright or square cells 1 and 2–4. 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. Laticifers or tanniniferous tubes absent.
Cambial variants. Included phloem absent. Other cambial variants absent.
Mineral inclusions. Crystals not observed. Cystoliths absent. Silica not observed.
Cite this publication as: H. G. Richter and M. J. Dallwitz (2000 onwards). 'Commercial timbers: descriptions, illustrations, identification, and information retrieval.' In English, French, German, and Spanish. Version: 4th May 2000. http://biodiversity.uno.edu/delta/.
Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993 onwards, 1995 onwards, 1998) should also be cited (see General references).