Otatea acuminata JAL

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 JAL ( Fig. 3 )

Material examined: — MEXICO. Jalisco: San Sebastián del Oeste, Mascota-Puerto Vallarta road, near arch bridge, 20°48’11”N, 104°56’13”W, 725 m, 28 July 2020, E . Ruiz-Sanchez 672 ( IBUG!) .

Culm anatomy description: —Culm solid ( Figs. 3A, B ). Epidermis with a layer of rounded lignified cells, 10 µm length, with frequent squared to rectangular silica bodies on top ( Fig. 3C ). Cortex with 3–4 layers of thick-walled rounded cells, followed by 1–2 layers of thinner-walled rounded cells (5–6 layers in total, 41 µm length; Fig. 3C ). Vascular bundles in 9–10 alternating cycles ( Fig. 3A ). Peripheral, transitional, and central vascular bundles surrounded by a sclerenchyma sheath defining their contour ( Figs. 3D–F ). Ovate central vascular bundles, 287 × 288 μm; two round shaped metaxylem vessels, 69 × 73 µm; phloem with sieve tubes and companion cells located between two metaxylem vessels on the upper level, 63 × 75 µm; sieve tubes 19 × 18 µm ( Fig. 3F ). Scarce amorphous silica bodies embedded along the periphery of vascular bundles occupying cellular spaces covering a mean area of 86 µm 2.

Figures

FIGURE 3. Culm cross section of Otatea acuminata JAL. A. Cross section general view. B. Central area with vascular bundles with different orientations. 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.