Mnesithea formosa

Mnesithea formosa (R. Br.) R. de Koning & M.S.M. Sosef. Blumea 31:288 (1986).

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

Basionym and/or Replacement Name:  Rottboellia formosa R. Br., Prodr. 1: 206 (1810).

Type of Basionym or Protologue Information: HT: Brown 6157, 1 Mar 1803, Australia: Bay of Carpentaria, Mallison Island (BM (photo, BRI, K); IT: K (photo, BRI), MEL (photo, BRI), NSW (photo, BRI)).

Recent synonyms: Rottboellia formosa.

Key references (books and floras): [1810]. R.Brown, Prodromus (206 as Rottboellia formosa), [1878] G.Bentham, Flora Australiensis 7 (513 as Rottboellia formosa), [1952] C.A.Gardner, Flora of Western Australia 1 Gramineae (308 as Rottboellia formosa), [1981] M.Lazarides in J.Jessop (ed)., Flora of Central Australia (495 as Rottboellia), [2002] D.Sharp & B.K.Simon, AusGrass, Grasses of Australia.

Illustrations: [1952] C.A.Gardner, Flora of Western Australia 1 Gramineae (307, Pl.90 as Rottboellia).

Habit. Annual. Culms erect, 10–60 cm tall. Mid-culm nodes glabrous. Lateral branches simple or sparsely branched or branched. Leaf-sheaths hairy. Ligule a fringed membrane, a ciliate membrane, 1–1.5 mm long. Leaf-blades 1–12 cm long, 1–4 mm wide.

Inflorescence. Inflorescence solid, a rame. Peduncle distinct. Rhachis fragile at the nodes.

Spikelets. Spikelets sessile, 1 in the cluster. Companion spikelets pedicelled, 1 in the cluster. Companion spikelets developed, comprising 2 unequal glumes without lemmas, 2.5–3 mm long. 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, ovate, terete, 1.8–2.2 mm long.

Glumes. Glumes dissimilar, firmer than fertile lemma. Lower glume ovate, indurate, keeled, 2-keeled. Lower glume surface indumented. Upper glume ovate, membranous, without keels. Upper glume surface glabrous. Florets. Basal sterile florets 1, male, with palea. Lemma of lower sterile floret hyaline.

Fertile lemma without keel.

Continental Distribution: Australasia.

Australian Distribution: Western Australia, Northern Territory, Queensland.

Western Australia: Gardner, Fitzgerald, Hall, Dampier. Fortescue. Northern Territory: Darwin & Gulf, Victoria River, Central Australia North. Queensland: Burke, Cook, Gregory North, North Kennedy, Port Curtis, South Kennedy.

Notes. Occurs in savanna woodlands of northern Australia extending to New Guinea. Flowers Feb.--July.


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