Otatea carrilloi, Ruiz-Sanchez, Sosa & Mejia-Saules

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 carrilloi ( Fig. 6 )

Material examined: — MEXICO. Chiapas: Tonalá, La Sepultura, vicinity of Raymundo Flores, 16°1’57.86”N, 93°36’12.20”W, 649 m, 15 February 2022, E . Ruiz-Sanchez et al. 730 ( IBUG!).

Culm anatomy description: —Culm hollow, the lacuna occupying> 50% of the total diameter. Epidermis with a layer of axially elongated lignified cells, 14 µm length, with frequent squared to rectangular silica bodies on top ( Fig. 6B ). Cortex with 2 layers of narrow thick-walled rounded cells, followed by 3–4 layers of wider thinner-walled rounded cells (in total, 5–6 layers, 61 µm length; Fig. 6B ). Vascular bundles in 10–11 alternating cycles ( Fig. 6A ). Peripheral, transitional, and central vascular bundles surrounded by a sclerenchyma sheath defining their contour ( Figs. 6C–E ). Cell wall of fiber sheath weakly lignified. Ovate central vascular bundles, 439 × 451 μm; two round shaped metaxylem vessels, 100 × 110 μm; phloem with sieve tubes and companion cells located between two metaxylem vessels on the upper level, 91 × 120 µm; sieve tubes 18 × 23 µm ( Fig. 6E ). Frequent amorphous silica bodies embedded along the periphery of vascular bundles occupying cellular spaces covering a mean area of 90 µm 2.

Figures

FIGURE 6. Culm cross section of Otatea carrilloi. 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.