Aristida jacobsiana

Aristida
jacobsiana
B.K.Simon & I.
Cowie. Telopea 13 (1–2): 150 (2011).

Type: Northern Territory: Nitmiluk National Park, 20 km N of Edith Falls: C.R. Michell
3717; holo: DNA; iso: BRI, CANB, NSW.

Habit.
Perennial. Culms 20–60 cm tall, 4–6 -noded. Mid-culm internodes glabrous.
Mid-culm nodes glabrous. Lateral branches simple or sparsely branched.
Leaf-sheaths smooth, glabrous on surface. Ligule absent. Leaf-blades filiform
or linear, flat or conduplicate or involute or convolute, 5–12 cm long, 1–2 mm
wide. Leaf-blade surface scaberulous, glabrous.

Inflorescence.
Panicle linear, 5–20 cm long, 0.5–2 cm wide.

Spikelets.
Spikelets pedicelled. Fertile spikelets comprising 1 fertile floret(s), without
rachilla extension, lanceolate, terete, 6–11 mm long.

Glumes. Glumes
similar, firmer than fertile lemma, dull. Lower glume lanceolate, membranous, 1
-nerved. Lower glume apex mucronate. Upper glume lanceolate, 6–11 mm long,
membranous, 1 -nerved. Upper glume apex mucronate.

Florets.
Fertile lemma 5.5–9 mm long, without keel, 3 -nerved. Lemma apex awned, 3
-awned. Median (principal) awn with a straight or slightly twisted column.
Column 1.5–2 mm long. Lateral lemma awns present.

Continental
Distribution
: Australasia.

Australian
Distribution
: Northern Territory, Queensland.

Northern Territory:
Darwin & Gulf. Queensland: Cook.


Telopea Description

Perennial, compactly tufted. Culms 20–60 cm tall, sometimes sparingly branched.
Culm internodes smooth, glabrous. Nodes 4–6, glabrous. Leaf sheaths longer than
internodes, smooth, glabrous. Ligule 0.2 mm long. Collar hairy. Auricles hairy. Hairs
to 2 mm long. Leaf blades 5–12 cm long, 1–2 mm wide, smooth, glabrous adaxially,
scaberulous, glabrous abaxially, involute, conduplicate or convolute or flat, setaceous
or not setaceous, not coiled or flexuose at maturity. Inflorescence 5–20 cm long,
0.5–2 cm wide, spiciform, continuous and dense or contracted or interrupted, stiffly
erect to loosely erect, branches 1–2.5 cm long, branches bearing spikelets from
base, branches bi-partite, branches without pulvini, branches tightly appressed to
loosely appressed, branches scabrous or scaberulous. Glumes normal. Lower glume
3.5–6.5 mm long, 1 - nerved, glabrous, smooth, acute to acuminate, entire, aristulate.
Arista 1–2 mm long. Upper glume 6–11 mm long, 1-nerved, glabrous, smooth, acute to
acuminate, entire, aristulate. Awn 0.5–1.5 mm long. Lemma 5.5–9 mm long, subequal
to one or both glumes, distinctly longer than lower, subequal to upper or slightly
longer than upper, convolute, smooth towards apex or scabrous only on keel, narrowed
upwards, without an articulation or pseudoarticulation. Callus 0.5–1 mm long, hairs
0.1–0.3 mm long. Column poorly developed, 1.5–2 mm long. Awns equal to subequal,
loosely spreading. Median awn 9–18 mm long, not geniculate, terete, straight. Lateral
awns 8–16 mm long, terete, straight.


Other specimens examined: Northern Territory: Nitmiluk National Park, Murrawal Plateau
North, C.R. Michell 3718 (BRI, CANB, DNA, NSW); Nitmiluk National Park, Fergusson R.
area, I.D. Cowie 9537 & A.K. Gibbons (BRI, DNA); Nitmiluk National Park, C.R. Michell 2952
& S. Boyce (DNA); Adelaide River, headwaters of Anniversary Ck, I.D. Cowie 4658 (BRI, DNA,
MEL). Queensland: Blackbraes National Park, 2.1 km from turn off from homestead, J. Kemp
BLAC09D (BRI); Amelia Downs Sation, 0.3 km S along Amelia-Bluff fence, J. Kemp AMEL11a
(BRI).
Derivation of epithet: named for Surrey Jacobs, Senior Principal Research Scientist
at the National Herbarium of New South Wales (NSW) and recently deceased. He
spent much of his time collecting grasses and water plants in tropical Australia and coauthored
four editions of Grasses of New South Wales (Wheeler et al. 1984, 1990, 2002;
Jacobs et al. 2008).
Flowering and fruiting: March and April.
Habitat: shale, quartzite and basalt soils in Eucalyptus or Corymbia woodland.

Australian
Distribution
: Northern Territory, Queensland.

Northern Territory:
Darwin & Gulf. Queensland: Cook.



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