Otatea transvolcanica, Ruiz-Sanchez & Clark

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 : 88

Otatea transvolcanica ( Fig. 12 )

Material examined: — MEXICO. Colima: Comala, dirt road Campo Cuatro to El Terrero, 19°24’05”N, 103°51’39”W, 1709 m, 25 July 2020, J. P . Ortíz-Brunel et al. 831 ( IBUG!).

Culm anatomy description: —Culm solid. Epidermis with a layer of axially elongated lignified cells, 12 µm length, with frequent squared to rectangular silica bodies on top ( Fig. 14B ). Cortex with one layer of narrow thick-walled rounded cells followed by 4–5 layers of wider, thinner-walled rounded cells (6–7 layers in total, 72 µm length; Fig. 14B ). Vascular bundles in 10–11 alternating cycles ( Fig. 14A ). Peripheral, transitional, and central vascular bundles surrounded by a sclerenchyma sheath defining their contour ( Figs. 14C–E ). Cell wall of fiber sheath weakly lignified. Elliptical central vascular bundles, 468 × 269 μm; two round shaped metaxylem vessels, 77 × 79 μm; phloem with sieve tubes and companion cells located between two metaxylem vessels on the upper level, 101 × 106 µm; sieve tubes 17 × 24 µm ( Fig. 14E ). Frequent amorphous silica bodies embedded along the periphery of vascular bundles occupying cellular spaces covering a mean area of 54 µm 2.

Figures

FIGURE 12. Culm cross section of Otatea transvolcanica. A. Cross section general view. B. Epidermis and cortex. C. Peripheral vascular bundle. D. Transitional vascular bundle. E. Central vascular bundle. Abbreviations: co, cortex; ep, epidermis; fs, fiber sheath; mx, metaxylem; pa, parenchyma; ph, phloem; px, protoxylem; sc, sclerenchyma; si, silica bodies.

FIGURE 14. Culm cross section of Otatea ximenae. A. Cross section general view. B. Central area with vascular bundles following different orientations. C. Epidermis and hypodermis. 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.