Rytidosperma pilosum

Rytidosperma pilosum (R.Br.) Connor &
Edgar. New Zealand J. Bot. 17(3): 326 (1979).

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

Basionym and/or
Replacement Name:
 Danthonia
pilosa
R.Br., Prodr. 177 (1810).

Type of Basionym or
Protologue Information
: HT: Brown 6234, Australia: New South Wales:
Port Jackson (BM; IT: K, MEL).

Recent synonyms:
Rytidosperma pilosum (R.Br.) Connor & Edgar var. paleaceum
(Vickery) Connor & Edgar, Notodanthonia pilosa (R.Br.) Zotov, Notodanthonia
pilosa
(R.Br.) Zotov var. paleacea (Vickery) Veldkamp, Austrodanthonia
pilosa
(R.Br.) H.P. Linder.

Key references
(books and floras):
[1810]. R.Brown, Prodromus (177 as Danthonia
pilosa
), [1878] G.Bentham, Flora Australiensis 7 (594 as Danthonia
pilosa
), [1952] C.A.Gardner, Flora of Western Australia 1 Gramineae
(56 as Danthonia pilosa), [2002] D.Sharp & B.K.Simon, AusGrass,
Grasses of Australia
, [2002] J.Wheeler, N.Marchant & M.Lewington, Flora
of the South West (401), [2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses
of South Australia
(294), [2008] S.W.L.Jacobs, R.D.B.Walley &
D.J.B.Wheeler, Grasses of New South Wales (145).

Illustrations:
[1952] C.A.Gardner, Flora of Western Australia 1 Gramineae (55,
Pl.14 as Danthonia), [2005] K.Mallet (ed.), Flora of Australia 44B:
Poaceae 3 (Fig.10, C-D), [2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses
of South Australia
 (294, Fig. 230
& plate 10), [2008] S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses
of New South Wales
, 4th edn (145).

Derivation: L. pilus,
a hair; -osa, abundance. The whole plant or any of its organs invested
with long spreading hairs.

Habit.
Perennial. Culms erect or geniculately ascending, 14–70 cm tall, 3–5 -noded.
Mid-culm nodes glabrous. Leaf-sheaths hairy. Ligule a fringe of hairs.
Leaf-blades flat or involute, 6–12 cm long, 1–2 mm wide.

Inflorescence.
Inflorescence solid, a panicle. Panicle lanceolate, 4–5 cm long.

Spikelets.
Spikelets pedicelled. Fertile spikelets many flowered, with at least 2 fertile
florets (5–9), comprising 5–9 fertile floret(s), with diminished florets at the
apex, cuneate, laterally compressed, 9–22 mm long.

Glumes. Glumes
similar, thinner than fertile lemma. Lower glume lanceolate, membranous, much
thinner on margins, keeled, 1-keeled, 5–7 -nerved. Upper glume lanceolate, 9–13
mm long, membranous, keeled, 1-keeled, 5 -nerved. Upper glume surface
asperulous.

Florets.
Fertile lemma 2.8–4 mm long, without keel, 9 -nerved. Lemma apex lobed, awned,
3 -awned. Median (principal) awn from a sinus, 11–18 mm long overall, with a
twisted column. Column 4 mm long. Lateral lemma awns present. Lodicules present.
Anthers 3. Grain 1.6–1.8 mm long.

Continental
Distribution
: Tropical Asia, Australasia, Pacific, and North America.

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

Western Australia:
Drummond, Dale, Eyre. South Australia: Flinders Ranges, Eyre Peninsula,
Northern Lofty, Murray, Southern Lofty, Kangaroo Island, South-eastern. New
South Wales
: Central Coast, South Coast, Northern Tablelands, Central
Tablelands, Southern Tablelands, Central-Western Slopes, South-Western Slopes. Victoria:
East Gippsland, Eastern Highlands, Gippsland Highlands, Gippsland Plain,
Grampians, Lowan Mallee, Midlands, Murray Mallee, Otway Plain, Otway Range,
Wilsons Promontory, Riverina, Snowfields, Volcanic Plain, Wannon, Wimmera. Tasmania:
Furneaux Group, North West, North East, Central Highlands, Midlands, Ben
Lomond, East Coast, South West.

Notes. R.
pilosum
is similar in appearance to R. racemosum and R.
penicillatum
, from which it can be distinguished by the intravaginal innovations,
which lead to a more caespitose habit; the densely compacted inflorescences;
the relatively longer awn-bases; and the paleas which are usually only
marginally longer than the lemma sinusses. However, depauperate specimens,
especially from the Northern Tablelands, can be difficult to place. There are
also some specimens which appear to be intermediate to A. caespitosum.

Widespread
south of the 32nd latitude, absent from the Nullabor Plain, altitude 10–1400 m,
very common and often co-dominant with A. caespitosa in grassland and
lightly shaded habitats. Flowers Nov. to Dec.

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