Iseilema convexum

Iseilema convexum C. E. Hubbard. Hooker's
Icon.Pl.
t.3286: 8 (1935).

Classification. (GPWG 2001) : Subfamily
Panicoideae. Andropogoneae.

Type of Basionym or
Protologue Information
: Australia,
Darling Downs, Bybera:  White 9741 .

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

Habit. Annual.
Culms erect or geniculately ascending, 30–70 cm tall, 2–3 -noded. Lateral
branches simple or sparsely branched. Ligule a fringed membrane, a ciliolate
membrane, 0.5 mm long. Leaf-blades flat or conduplicate, 9–18 cm long, 3–5.5 mm
wide. Leaf-blade surface scaberulous.

Inflorescence.
Inflorescence compound, composed of rames.

Spikelets.
Spikelets sessile, 1 in the cluster. Companion spikelets pedicelled, 2 in the
cluster. Basal sterile spikelets well-developed, 4 in number. Companion
spikelets developed, containing empty lemmas or male, 3–4 mm long. Companion
spikelet glumes muticous. 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, lanceolate,
dorsally compressed, 5.5–6.5 mm long.

Glumes. Glumes
dissimilar, firmer than fertile lemma. Lower glume elliptic, coriaceous,
without keels, 8–9 -nerved. Lower glume surface indumented. Upper glume
lanceolate, coriaceous, 3 -nerved. Upper glume surface indumented. Florets.
Basal sterile florets 1, barren, without significant palea. Lemma of lower
sterile floret hyaline, 0 -nerved. Fertile florets female.

Fertile lemma 2.5–3 mm
long, 1 -nerved. Lemma apex lobed, awned, 1 -awned. Median (principal) awn from
a sinus, 16–20 mm long overall, with a twisted column. Column 8–10 mm long.
Palea absent. Anthers 3. Grain 2.5 mm long.

Continental
Distribution
: Australasia.

Australian
Distribution
: Northern Territory, Queensland.

Northern Territory: Barkly Tableland.
Queensland:
Burke, Gregory North, Mitchell.

Notes. Growing
in cracking clay soils on Barkly Tableland of N.T. and Mitchell grass Downs of
Qld. Flowers Mar.--Aug.

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