Otatea ramirezii (Fig. 9)

Material examined: — MEXICO. Querétaro: San Joaquín, along dirt road from Apartadero to San Juan Tetla, 20°58’56”N, 99°29’28”W, 1285 m, 19 February 2022, J. P . Ortíz-Brunel et al.1395 (IBUG!) .

Culm anatomy description: —Culm solid. Epidermis with a layer of axially elongated lignified cells, 11 µm length, with frequent squared to rectangular silica bodies on top (Fig. 9B). Cortex with one layer of narrow thick-walled cells followed by 2–3 layers of wider thinner-walled rounded cells (in total, 3–4 layers, 28 µm length; Fig. 9B). Vascular bundles in 9–10 alternating cycles. Peripheral, transitional, and central vascular bundles surrounded by a sclerenchyma sheath defining their contour (Figs. 9C–E). Oval central vascular bundles, 275 × 297 μm; two round shaped metaxylem vessels, 77 × 81 μm; phloem with sieve tubes and companion cells located between two metaxylem vessels on the upper level, 73 × 97 µm; sieve tubes 20 × 20 µm (Fig. 9E). Sporadic conical silica bodies across the ground tissue occupying intercellular spaces covering a mean area of 26 µm 2.