Otatea acuminata AGS

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 : 78

Otatea acuminata AGS ( Fig. 2 )

Material examined: — Aguascalientes: Calvillo, Jagúey canyon, 3 km E of Piedras Chinas , 1.5 km N of El Zapote de la Labor , 21°58’46.99”N, 102°39’23.2”W, 1969 m, 9 June 2020, E . Ruiz-Sanchez & M. A . García-Martínez 652 ( IBUG!) .

Culm anatomy description: —Culm solid. Epidermis with a layer of axially elongated lignified cells, 12 µm length, with axially elongated silica bodies ( Fig. 2B ). Cortex with 2 layers of narrow thick-walled cells followed by 3–4 layers of thinner-walled rounded cells (5–6 layers in total, 70 µm length; Fig. 2B ). Vascular bundles in 8–9 alternating cycles ( Fig. 2A ). Peripheral, transitional, and central vascular bundles surrounded by a sclerenchyma sheath defining their contour ( Figs. 2C–E ). Elliptical central vascular bundles, 488 × 444 μm; two round shaped metaxylem vessels, 98 × 106 µm; phloem with sieve tubes and companion cells located between two metaxylem vessels on the upper level, 119 ×136 µm; sieve tubes 24 µm × 23 µm ( Fig. 2E ). Scarce amorphous silica bodies embedded along the periphery of vascular bundles occupying cellular spaces covering a mean area of 70 µm 2. Sporadic conical silica bodies across the ground tissue occupying intercellular spaces covering a mean area of 30 µm 2.

Figures

FIGURE 2. Culm cross section of Otatea acuminata AGS. 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.