Rytidosperma petrosum

Detailed description

Stiff, wiry and rather dense tufted grass forming small tussocks in rock cracks and amongst saxicolous lichens in sunny sites. Tufts forming at ends of elongating shoots, rooting at nodes; leaves less than or equal to culms, more or less pungent, disarticulating at ligule; branching intravaginal. Leaf-sheath glabrous, light grey to dark brown drying straw-yellow to white; apical tuft of hairs 1–1.5 mm. Ligule c. 0.5 mm. Leaf-blade to 150 mm, glabrous, stiff, inrolled margins glabrous. Culms to 400 mm internodes glabrous. Inflorescence a raceme or racemose panicle small, erect, to 40 mm, of very few large spikelets on short pedicels; rachis and pedicels almost glabrous with only a few scattered teeth and usually small tufts of long hairs at branch axils. Spikelets 4–6-flowered, awns and sometimes lemma lobes exserted from glumes. Glumes green, lanceolate, acute, 8.5–15 mm more or less equal; lower 5–(7)-nerved, upper 3-nerved. Lemma 2.5–3.5 mm, 9-nerved, upper row of hairs interrupted, dense marginal tufts with few additional hairs adjacent, hairs very much less than lemma lobes, lower row more or less continuous, with dense strong marginal tuffs and less dense tufts between, overlapping upper, glabrous elsewhere; lobes 4.5–8 mm, narrowing to strong awn and often shortly lobed at awn base; central awn 7.5–14 mm, column 2.5–4 mm, less than upper lemma hairs. Callus 0.7–1 mm, strong marginal hair tufts overlapping lower lemma hairs. Rachilla 0.5–0.6 mm. Anthers 0.7–1.5 mm, yellow. Seed 2.5 × 1.0 mm.