Classification
Class
Magnoliopsida Brongn.
Order
Poales Small
Family
Gramineae Juss.
Genus
Rytidosperma Steud.
 Nomenclature
Scientific Name:
Rytidosperma petrosum Connor & Edgar, New Zealand J. Bot. 17: 317 (1979)
 Description

Stiff, wiry, small tussocks, tufts formed at ends of elongating shoots, rooting at nodes; leaves ≤ culms, semi-pungent, disarticulating at ligule; branching intravaginal. Leaf-sheath glabrous, light grey to dark brown; apical tuft of hairs 1–1.5 mm. Ligule c. 0.5 mm. Leaf-blade to 15 cm, glabrous, stiff, inrolled, margins glabrous. Culm to 40 cm, internodes glabrous. Raceme or racemose panicle small, erect, to 4 cm, 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, ± equal; lower 5–(7)-nerved, upper 3-nerved. Lemma 2.5–3.5 mm, 9-nerved, upper row of hairs inter-rupted, dense marginal tufts and a few additional hairs adjacent, hairs « lemma lobes, lower row almost continuous, with dense strong marginal tufts 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, > upper lemma hairs. Palea 3.6–6 mm, = or slightly > upper lemma hairs, interkeel glabrous, margins with 1–2 long hairs. Callus 0.7–1 mm, strong marginal hair tufts overlapping lower lemma hairs. Rachilla 0.5–0.6 mm. Anthers 0.7–1.1 and 1.5 mm, yellow. Caryopsis c. 2.5 × 1.0 mm; embryo c. 1.0 mm; hilum 0.5 mm. Plate 11G.

[From: Edgar and Connor (2000) Flora of New Zealand. Volume 5 (second printing).]

 Biostatus
Indigenous (Endemic)
 Bibliography
Connor, H. E.; Edgar, E. 1979: Rytidosperma Steudel (Notodanthonia Zotov) in New Zealand. New Zealand Journal of Botany 17: 311–337.
de Lange, P.J.; Norton, D.A.; Courtney, S.P.; Heenan, P.B.; Barkla, J.W.; Cameron, E.K.; Hitchmough, R.; Townsend, A.J. 2009: Threatened and uncommon plants of New Zealand (2008 revision). New Zealand Journal of Botany 47: 61–96. [Naturally uncommon]
de Lange, P.J.; Norton, D.A.; Heenan, P.B.; Courtney, S.P.; Molloy, B.P.J.; Ogle, C.C.; Rance, B.D. 2004: Threatened and uncommon plants of New Zealand. New Zealand Journal of Botany 42(1): 45–76.
de Lange, P.J.; Rolfe, J.R.; Barkla J.W.; Courtney, S.P.; Champion, P.D.; Perrie, L.R.; Beadel, S.N.; Ford, K.A.; Breitwieser, I.; Schönberger, I.; Hindmarsh-Walls, R.; Heenan, P.B.; Ladley, K. 2018: Conservation status of New Zealand indigenous vascular plants, 2017. New Zealand Threat Classification Series. No. 22. [Naturally Uncommon]
de Lange, P.J.; Rolfe, J.R.; Champion, P.D.; Courtney, S.P.; Heenan, P.B.; Barkla, J.W.; Cameron, E.K.; Norton, D.A.; Hitchmough, R.A. 2013: Conservation status of New Zealand indigenous vascular plants, 2012. New Zealand Threat Classification Series 3. Department of Conservation, Wellington. [Naturally Uncommon]