Rytidosperma dimidiatum

Rytidosperma dimidiatum (Vickery) H.E.
Connor & E. Edgar. New Zealand J. Bot. 17: 332 (1979).

Classification. (GPWG 2001) : Subfamily Danthonioideae. Tribe

Basionym and/or
Replacement Name:
Vickery, Contr. New South Wales Natl. Herb. 2: 322 (1956).

Type of Basionym or
Protologue Information
: HT: Rodway s.n., Australia (HO).

Recent synonyms:
Notodanthonia dimidiata, Danthonia dimidiata.

Key references
(books and floras):
[2002] D.Sharp & B.K.Simon, AusGrass, Grasses of

Perennial. Culms erect or geniculately ascending, stature slender to delicate,
15–40 cm tall, 2–4 -noded. Mid-culm nodes glabrous. Leaf-sheaths glabrous on
surface or hairy. Ligule a fringe of hairs. Leaf-blades involute, 2–12 cm long,
1–1.5 mm wide. Leaf-blade surface glabrous or indumented.

Inflorescence solid, a panicle. Panicle linear or lanceolate, 2–6 cm long.

Spikelets pedicelled. Fertile spikelets many flowered, with at least 2 fertile
florets (4–7), comprising 4–7 fertile floret(s), with diminished florets at the
apex, cuneate, laterally compressed, 5–11 mm long.

Glumes. Glumes
similar, thinner than fertile lemma. Lower glume lanceolate, membranous,
without keels, 7 -nerved. Upper glume lanceolate, 5–11 mm long, membranous,
without keels, 7 -nerved.

Fertile lemma 2.5–7 mm long, without keel, 9 -nerved. Lemma surface indumented.
Lemma apex lobed, awned, 1 -awned. Median (principal) awn from a sinus, 7.5–9.5
mm long overall, with a twisted column. Column 4 mm long. Lateral lemma awns
absent. Lodicules present. Anthers 3. Grain 1.5–1.6 mm long.

: Australasia.

: Victoria, Tasmania.

Gippsland Plain. Tasmania: North East, West Coast, Central Highlands,
Midlands, Ben Lomond, East Coast, South West.

R. dimidiatum is closely related to R. fortunae-hibernae and R.
. It differs from the former species by the laxer growth and
larger spikelets; Morris (1992) separates it by a lax ring of lemma hairs
compared to a dense ring directly below the sinus in R. fortunae-hibernae.
It is readily distinguished from R. pauciflorum by the much larger
spikelets and the poorly developed upper row of lemma hairs.

AVH 2011


and the southern coast of Victoria, altitude 0–1150 m, various habitats, from
moorland to dry grassland, in exposed places. Flowers Dec.

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