16. Bromus riparius Rehmann, Verh. Naturf. Vereins Brünn. 10: 8. 1872 [“1871”].
山丹雀麦 shan dan que mai
Bromopsis riparia (Rehmann) Holub; Zerna riparia (Rehmann) Nevski.
Perennial, with short rhizomes, base covered by fibrous dry leaf sheaths. Culms densely tufted, 30–50(–90) cm tall. Leaf sheaths ± scattered villous; leaf blades narrowly linear, 15–20 cm × 1–2 mm, scabrid, margins ciliate; ligule short. Panicle lax, 10–15 × ca. 10 cm; branches obliquely erect, scabrid, bearing 1 or 2 spikelets. Spikelets wedge-shaped, 25–35 × 6–7 mm, florets 5–7, lax; rachilla 3–4 mm, shortly hairy, laterally visible; glumes apex acuminate, lower glume 8–10 mm, 1–3-veined, upper glume 9–12 mm; lemmas 11–13 mm, puberulous along sides or throughout, 5–7-veined, membranous, apex acuminate; awn 5–8 mm, slender, straight; palea shorter than lemma, keels spinulose. Anthers ca. 6 mm. Fl. and fr. May–Jul. 2n = 56.
Dry meadows, grasslands, forest margins, low-mountain thickets, on calcareous soils. Gansu [Russia (European part, adventive in Far East); SW Asia, Europe].
No specimens of this species were found in PE.