Lamarckia

Lamarckia* Meth. 201(1794).

Derivation:.
Named for Jean-Baptiste Lamarck, French naturalist of the eighteenth
century.

Key references
(keys and floras):
. G.Bentham, Flora Australiensis 7: 636 (1878);
C.A.Gardner, Flora of Western Australia 1 Gramineae 42–43 (1952);
J.C.Tothill and J.B.Hacker, Grasses of Southern Queensland 292–293
(1983); J.P.Jessop, Flora of South Australia 4: 1892 (1986); B.K.Simon, Key
to Australian Grasses
128 (1993); S.W.L.Jacobs and K.L.McClay, Flora of
New South Wales
4: 604 (1990); N.G.Walsh, Flora of Victoria 2: 410
(1994); D.Sharp and B.K.Simon, AusGrass (2002); J.P.Jessop, Grasses
of South Australia
129–130 (2006) S.W.L.Jacobs, R.D.B.Whalley &
D.J.B.Wheeler, Grasses of New South Wales, 4th ed, 291 (2008); A.Wilson
(ed.), Flora of Australia 44A: Poaceae 2: 346–347 (2009).

W.D.Clayton &
S.A.Renvoize, Genera Graminum (1986), genus (118).

Naturalised. 1
species, from the Mediterranean to Pakistan. WA, SA, Qld, NSW, and Vic.

Habit. Annual,
tufted. Leaf blades narrow. Ligule an unfringed membrane.

Inflorescence.
Inflorescence a false spike, with spikelets on contracted axes (the spikelets
in peduncled fascicles, with only the terminal spikelet fertile, the others in
the clauser male or sterile), a spike-like panicle, contracted. Spikelet-bearing
axes falling entire (the clusters of 3–5 spikelets falling whole).

Spikelets.
Spikelets laterally compressed, more than 2 flowered or 2 flowered, with 1
fertile floret, awned, solitary, pedicelled (the pedicels villous); with naked
rachilla extension. Fertile spikelets cuneate, falling with glumes (in the
clusters), with a distinctly elongated rachilla internode above glumes and with
distinctly elongated rachilla internodes between florets.

Glumes. Glumes
more or less equal, about equal to spikelet to exceeding florets, long relative
to adjacent lemmas, hairless, pointed, awned to awnless (acuminate to shortly
aristate), keeled, similar (membranous, linear-lanceolate, hyaline). Lower
glume 1 nerved. Upper glume 1 nerved.

Florets.
Fertile florets 1. Lemmas papery, not becoming indurated, entire at apex to
incised, awned, 4–5 nerved, glabrous. Awns 1, from a sinus or apical,
non-geniculate, straight or recurving, much longer than body of lemma (4.7–7.2
mm long). Palea relatively long, tightly clasped by lemma, textured like lemma
(membranous), 2 nerved. Palea keels wingless. Distal incomplete florets 1.
Callus short, blunt (glabrous). Lodicules 2. Stamens 3. Grain small, ovoid or
ellipsoid, ventrally longitudinally grooved, glabrous. Hilum short (elliptic).
Embryo small.

Kranz Anatomy.
C3.

2n = 14,
2 ploid, commonly adventive.

Habitat.
Mesophytic, xerophytic. Dry places. Species of open habitats.

Classification.
Pooideae; Poeae.

Types Species. L.
aurea
(L.) Moench.

Biogeographic
Element
. Clifford & Simon 1981, Simon & Jacobs 1990: Naturalised.

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