Otatea fimbriata, Soderstrom

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 : 82

Otatea fimbriata ( Fig. 7 )

Material examined: — MEXICO. Chiapas: Ixtapa, Km 20 toll road Tuxtla Gutiérrez-San Cristóbal de las Casas , 16°41’53.31”N, 92°51’48.14”W, 1300 m, 15 February 2022, E . Ruiz-Sanchez et al. 732 ( 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. 7B ). Cortex with 1–2 layers of narrow thick-walled rounded cells followed by 4–5 layers of wider and thinner-walled rounded cells (6–7 layers in total, 73 µm length; Fig. 7B ). Vascular bundles in 11–12 alternating cycles ( Fig. 7A ). Peripheral, transitional, and central vascular bundles surrounded by a sclerenchyma sheath defining their contour ( Figs. 7C–E ). Elliptical central vascular bundles, 556 × 615 μm; two round shaped metaxylem vessels, 119 × 117 μm; phloem with sieve tubes and companion cells located between two metaxylem vessels on the upper level, 115 × 195 µm; sieve tubes 20 × 27 µm ( Fig. 7E ). Scarce amorphous silica bodies embedded along the periphery of vascular bundles occupying cellular spaces covering a mean area of 127 µm 2. Frequent conical silica bodies across the ground tissue occupying intercellular spaces covering a mean area of 20 µm 2.

Figures

FIGURE 7. Culm cross section of Otatea fimbriata. 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.