Poa pygmaea

Detailed description

Small, dull grey-green to green, much-branched, very densely packed perennial, rooting from short prostrate branches and forming compact, rigid cushions to 100 × 25 mm high, slightly overtopped by filiform flowering culms with few spikelets. Branching intravaginal, new shoots with densely imbricating leaves; leaf-blades persistent. Leaf-sheath much wider than leaf-blade, pale greyish brown, membranous, glabrous, shining, ± indistinctly ribbed. Ligule 0.5–1.0 mm, apically glabrous, entire, narrowed centrally to a short point, underside sparsely to densely minutely pubescent. Leaf-blade 3–7 × 1–2 mm, stiff, inrolled, underside glabrous, ribs prominent, upper surface strongly ribbed, ribs whitish with fine minute hairs or prickle-teeth; midrib scabrid near very curved, subobtuse or occasionally acute tip. Culm 15–25 mm, internodes mainly smooth with a few minute prickle-teeth above. Panicle 5–10 mm, contracted, racemose, with 1–3 spikelets; branches and pedicels glabrous. Spikelets 4.5–5.5 mm, 2–5-flowered, light green to purplish. Glumes equal, 2.5–3.5 mm, 3-nerved, ovate-elliptic, subobtuse, smooth or rarely with a few prickle-teeth on midnerve near tip; margins entire. Lemma 3.0–3.5 mm, 5-nerved, ovate, obtuse, lower ½ with fine, often crinkled hairs on nerves and sparse somewhat shorter hairs on internerves, upper ½ sparsely scabrid on midnerve and near wide membranous margin; midnerve occasionally minutely excurrent. Palea 2.5–3.0 mm, keels ciliate, interkeel with sparse minute hairs. Callus with few long hairs. Rachilla 0.5 mm, sparsely ciliate; prolongation twice as long. Lodicules 0.4–0.6 mm. Anthers 1.2–1.6 mm. Seeds c. 1.5–2.0 × 0.5 mm.