Otatea acuminata OAX

García-Martínez, Miguel A., Terrazas, Teresa, Sánchez, Daniel, Reyes, Pablo Carrillo- & Ruiz-Sanchez, Eduardo, 2023, Culm anatomy of the genus Otatea (Poaceae, Bambusoideae, Bambuseae, Guaduinae) as a contribution to Mexican species identification, Phytotaxa 609 (2), pp. 75-102 : 80-81

Otatea acuminata OAX ( Fig. 4 )

Material examined: — Oaxaca: Tepelmeme Villa de Morelos, Km 107, Puebla-Oaxaca toll road, Puente Los Otates , 18°1’53.2”N, 97°20’58.7”W, 1961 m, 1 February 2020, E . Ruiz-Sanchez & M. A . García-Martínez 644 ( IBUG!) .

Culm anatomy description: —Culm solid. Epidermis with a layer of axially elongated lignified cells, 12 µm length, with frequent silica bodies on top ( Fig. 4C ). Cortex with one layer of narrow thick-walled rounded cells followed by 3–4 layers of wider thin-walled rounded cells (4–5 layers in total, 43 µm wide), the inner ones only with primary walls, chloroplasts and dark staining deposits in some cells ( Fig. 4C ). Vascular bundles in 11–12 alternating cycles ( Fig. 4A ). Peripheral, transitional, and central vascular bundles surrounded by a lignified sclerenchyma sheath defining their contour ( Figs. 4D–F ). Cell wall of fiber sheath weakly lignified. Ovate central vascular bundles, 426 × 392 μm; two round shaped metaxylem vessels, 93 × 89 μm, phloem with sieve tubes and companion cells located between two metaxylem vessels on the upper level, 93 × 136 µm; sieve tubes 17 × 21 µm ( Fig. 4F ). Scarce amorphous silica bodies embedded along the periphery of vascular bundles occupying cellular spaces covering a mean area of 49 µm 2. Sporadic conical silica bodies across the ground tissue occupying intercellular spaces covering a mean area of 17 µm 2 ( Fig. 4B ).

Figures

FIGURE 4. Culm cross section of Otatea acuminata OAX. A. Cross section general view.B. Parenchymatous ground tissue with sporadic conical silica bodies. C. Epidermis and cortex. D. Peripheral vascular bundle. E. Transitional vascular bundle. F. Central vascular bundle. Abbreviations:co, cortex; ep, epidermis; fs, fiber sheath; mx, metaxylem; pa, parenchyma; ph, phloem; px, protoxylem; sc, sclerenchyma; si, silica bodies.