Rytidosperma richardsonii


Rytidosperma richardsonii (Cashm.) Connor
& Edgar. New Zealand J. Bot. 17: 332 (1979).

Classification. (GPWG 2001) : Subfamily Danthonioideae. Tribe
Danthonieae.

Basionym and/or
Replacement Name:
 Danthonia
richardsonii
Cashmore, Comm. Austr., C.S.I.R., Bull. 69(app.): 2
(1932).

Type of Basionym or
Protologue Information
: HT: Cashmore Ga-63, 2 Dec 1932, Australia:
South Australia: Werribee (AD; IT: BM, K, NSW-4726, NSW-1204). HT originally at
ADW.

Recent synonyms:
Notodanthonia richardsonii (Cashm.) Veldkamp, Austrodanthonia
richardsonii
(Cashmore) H.P. Linder.

Key references
(books and floras):
[2002] D.Sharp & B.K.Simon, AusGrass, Grasses of
Australia
, [2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses of South
Australia
(295), [2008] S.W.L.Jacobs, R.D.B.Walley & D.J.B.Wheeler, Grasses
of New South Wales
(146).

Illustrations:
[2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses of South Australia  (296, Fig. 232), [2008] S.W.L.Jacobs,
R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th edn
(146).

Derivation: in
honor of Arnold Edwin Victor Richardson (1883–1949). Australian agricultural
scientist.

Habit.
Perennial. Culms erect, 30–70 cm tall, 1 mm diam., 4 -noded. Leaf-sheaths
smooth. Ligule a fringe of hairs. Leaf-blades flat or involute, 20–30 cm long,
1–2.5 mm wide. Leaf-blade surface glabrous or indumented.

Inflorescence.
Inflorescence solid, a panicle. Panicle lanceolate or ovate, 4–12 cm long.

Spikelets.
Spikelets pedicelled. Fertile spikelets many flowered, with at least 2 fertile
florets (5), comprising 5 fertile floret(s), with diminished florets at the
apex, cuneate, laterally compressed, 8–13 mm long.

Glumes. Glumes
similar, thinner than fertile lemma. Lower glume elliptic, membranous, without
keels, 5–7 -nerved. Upper glume elliptic, 8–13 mm long, membranous, without
keels, 5–7 -nerved.

Florets.
Fertile lemma 3–4.1 mm long, without keel, 9 -nerved. Lemma surface indumented.
Lemma apex lobed, awned, 3 -awned. Median (principal) awn from a sinus, 7–11 mm
long overall, with a twisted column. Lateral lemma awns present. Lodicules
present. Anthers 3. Grain 2–2.1 mm long.

Continental
Distribution
: Australasia.

Australian
Distribution
: South Australia, New South Wales, Victoria.

South Australia:
Southern Lofty. New South Wales: North Coast, Central Coast, Northern
Tablelands, Central Tablelands, Southern Tablelands, North-Western Slopes,
Central-Western Slopes, South-Western Slopes, North-Western Plains,
South-Western Plains. Victoria: Riverina, Volcanic Plain.

Notes. R.
richardsonii
is very similar to some forms of R. bipartitum, but it
can be distinguished by the broader florets, particularly the glumes and
paleas, and by the more compact inflorescences.

Widespread
on the Tablelands and Western Slopes of New South Wales, reaching to near the
South Australian border, altitude 300–1000 m. Flowers Nov.

 

AVH 2011

   

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith