Otatea reynosoana (Fig. 10)

Material examined: — MEXICO. Michoacán: Morelia, Filtros Viejos, on the banks of the Chiquito river, 19°40’35.2”N, 101°9’13.7”W, 1947 m, 3 February 2020, E . Ruiz-Sanchez & M. A . García-Martínez 649 (IBUG!) .

Culm anatomy description: —Culm hollow, the lacuna occupying <50% of the total diameter. Epidermis with a layer of square to rectangular thick-walled cells, 11 µm length, with occasional rectangular silica bodies on top (Fig. 10C). Cortex with 3–4 layers of thick-walled rounded cells, the outer narrower, 27 µm length, with dark staining deposit (Fig. 10C). Vascular bundles in 5–6 alternating cycles (Fig. 10C). Peripheral, transitional, and central vascular bundles surrounded by a sclerenchyma sheath defining their contour (Figs. 10D–F). Depressed central vascular bundles, 249 × 351 μm; two round shaped metaxylem vessels, 80 × 88 μm; phloem with sieve tubes and companion cells located between two metaxylem vessels on the upper level, 56 × 91 µm; sieve tubes 19 × 21 µm (Fig. 10F). Scarce amorphous silica bodies embedded along the periphery of vascular bundles occupying cellular spaces covering a mean area of 78 µm 2. Sporadic conical silica bodies across the ground tissue occupying intercellular spaces covering a mean area of 11 µm 2 (Fig. 10B).