|
Note - this takes you off
of our website |
GrassBase - The Online World Grass Flora
Descriptions
W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson
© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.
Rytidosperma petrosum
HABIT Perennial; caespitose. Basal innovations intravaginal. Culms 20–40 cm long; rooting from lower nodes. Leaf-sheaths glabrous on surface. Ligule a fringe of hairs; 0.5 mm long. Leaf-blades deciduous at the ligule; involute; 7–15 cm long; 1–2 mm wide; stiff.
INFLORESCENCE Inflorescence a panicle.
Panicle open; ovate; 2–4 cm long; bearing few spikelets. Primary panicle branches indistinct the panicle almost racemose. Panicle branches smooth; bearded in axils.
Spikelets solitary. Fertile spikelets pedicelled. Pedicels smooth.
FERTILE SPIKELETS Spikelets comprising 4–6 fertile florets; with diminished florets at the apex. Spikelets cuneate; laterally compressed; 8.5–15 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 0.5–0.6 mm long. Floret callus evident; 0.7–1 mm long; pilose.
GLUMES Glumes persistent; similar; shorter than spikelet, or reaching apex of florets; thinner than fertile lemma. Lower glume lanceolate; 8.5–15 mm long; 1 length of upper glume; membranous; mid-green; without keels; 5(–7) -veined. Lower glume apex acute. Upper glume lanceolate; 8.5–15 mm long; 1.2–1.3 length of adjacent fertile lemma; membranous; mid-green; without keels; 3 -veined. Upper glume apex acute.
FLORETS Fertile lemma oblong; 7–11.5 mm long; chartaceous; without keel; 9 -veined. Lemma surface with a transverse row of hair tufts and with marginal hair tufts (above). Lemma apex lobed; 2 -fid; with simple equal lobes, or with lateral lobes bidentate; with lobes 4.5–8 mm long; incised 0.6–0.7 of lemma length; awned; 3 -awned. Principal lemma awn from a sinus; geniculate; 7.5–10 mm long overall; with twisted column. Column of lemma awn 2.5–4 mm long. Lateral lemma awns arising on apex of lobes. Palea 3.6–6 mm long. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.
FLOWER Lodicules 2; fleshy; ciliate. Anthers 3; 0.7–1.1 mm long; yellow.
FRUIT Caryopsis with adherent pericarp; 2.5 mm long.
DISTRIBUTION Australasia: New Zealand.
NOTES Arundineae. Connor & Edgar 1993.
Please cite this publication as detailed in How to Cite Version: 3rd February 2016.
