Yakirra nulla Lazarides &
R.D.Webster. Brunonia 7: 295
Classification. (GPWG 2001) : Subfamily
Type of Basionym or
Protologue Information: Australia:
Darwin & Gulf District: ca. 8 mi NE of Adelaide River township, 17 Mar
1965, Lazarides & Adams 262 (HT: CANB; IT: K, L, NT).
from the Latin nullus (nothing). Apex of the stipe lacks appendages.
or perennial. Culms erect or decumbent, 50–60(–100) cm tall, 4–6 -noded.
Mid-culm internodes hollow, glabrous or hirsute. Mid-culm nodes glabrous or
pubescent. Lateral branches sparsely branched. Leaf-sheaths hairy. Ligule a
fringe of hairs, 0.5–2 mm long. Leaf-blades 3–8(–17) cm long, 2–10 mm wide.
Leaf-blade surface scabrous, glabrous or indumented.
Inflorescence compound, a panicle. Panicle ovate, 5–23 cm long, 4–12 cm wide,
contracted about primary branches or with spikelets clustered towards branch
Spikelets pedicelled. Fertile spikelets 2-flowered, the lower floret barren
(rarely male), the upper fertile, comprising 1 basal sterile florets,
comprising 1 fertile floret(s), without rachilla extension, elliptic or
oblanceolate, dorsally compressed, 3.8–5.1 mm long. Rhachilla internodes
elongated between glumes.
dissimilar, thinner than fertile lemma. Lower glume ovate, membranous, without
keels, 3–5 -nerved. Upper glume elliptic, 4.1–5.1 mm long, membranous, without
keels, 7 -nerved. Florets. Basal sterile florets 1, barren, with palea
or without significant palea. Lemma of lower sterile floret 100 % of length of
spikelet, membranous, 5 -nerved.
Fertile lemma 2.5–3.8
mm long, without keel, 7 -nerved. Lodicules absent or vestigial. Anthers 3.
Grain 1.7 mm long.
Distribution: Northern Territory.
Northern Territory: Darwin &
Similar to the typical form of Y. pauciflora but easily distinguished by
the absence of lateral appendages at the apex of the swollen rachilla.
Restricted to a
relatively small area E and SE of Darwin. N.T. In tropical and subtropical
sub-humid woodlands and coastal grasslands. Flowers Feb.-May.