Mnesithea Rev. Gram. 1: 153 (1829).

Derivation:. In honour of Mnesitheos, Greek physician and writer on edible plants fide H.T.Clifford, Etymological Dictionary of Grasses (1996).

Syn: Coelorachis Brongn; Hackelochloa Kuntze; Heteropholis C.E.Hubb.

Taxonomic revisions, nomenclatural references:. J.F.Veldkamp, R. de Koning and M.S.M.Sosef, Blumea 31: 281–307 (1986); B.K Simon, Austrobaileya 3: 90 (1989).

Key references (keys and floras):. G.Bentham, Flora Australiensis 7: 511–512 (1878) as Manisuris; C.A.Gardner, Flora of Western Australia 1 Gramineae 304 (1952) as Coelorachis, 306–308 as Hackelochloa and 308 as Rottboellia; E.E.Henty, Manual Grasses New Guinea 51, 53 (1969) as Coelorachis, 105 as Hackelochloa; M.Lazarides, Flora of Central Australia 484–485 (1981) as Rottboellia; M.Lazarides, Tropical Grasses S.E. Asia 59 (1980), 28–29 as Coelorachis and 43 as Hackelochloa; J.C.Tothill and J.B.Hacker, Grasses of Southern Queensland 166–167(1983) as Coelorachis, 254–255 as Hackelochloa; B.K.Simon, Flora of the Kimberley Region 1190–1191 (1992); B.K.Simon, Key to Australian Grasses 132 (1993); D.Sharp and B.K.Simon, AusGrass (2002).

W.D.Clayton & S.A.Renvoize, Genera Graminum (1986), genus (632, 636, 637, 642).

Native. 32 species, from pantropic regions. 5 species in Australia, WA, NT, and Qld. Also New Guinea and Malesia.

Habit. Annual or perennial, rhizomatous or tufted. Leaf blades broad or narrow. Ligule an unfringed membrane or a fringed membrane.

Inflorescence. Inflorescence a single raceme or paniculate, a spike-like panicle, open, spatheate, racemes single, not in tight heads or racemes paired or in clusters, not in tight heads, a compound pseudo-inflorescence. Spikelet-bearing axes racemes, with heteromorphic spikelets, solitary, with spikelets in pairs, one sessile, the other pedicelled, disarticulating at joints. Internodes with a basal callus-knob, disarticulating transversely, somewhat hairy or glabrous.

Spikelets. Spikelets all partially embedded in rachis, dorsally compressed, 2 flowered, with 1 fertile floret, awned, paired, sessile and pedicelled, in pedicelled/sessile combinations; sessile spikelet with lower incomplete floret. Fertile spikelets falling with glumes.

Glumes. Glumes more or less equal, long relative to adjacent lemmas, awnless, dissimilar. Lower glume two-keeled, convex on back to flattened on back, relatively smooth or lacunose with deep depressions or rugose.

Florets. Lower incomplete floret(s) sterile. Lemmas awnless, more or less equalling fertile lemmas, becoming indurated. Lemmas less firm than glumes, entire at apex, glabrous. Palea relatively long or very reduced, entire. Stamens 33. Pedicels discernible, but fused with rachis, or free of rachis. Pedicelled spikelets present, similar in shape to sessile spikelet, male.

Kranz Anatomy. C4.

Habitat. Mesophytic.

Classification. Panicoideae; Andropogoneae.

Notes. In the treatment by Veldkamp, de Konig and Sosef (1986), a number of elements were placed together on the basis of preliminary cladistic work, although some workers considered that Veldkamp et al. have taken an extreme position in the number of genera they have placed together. This treatment follows Veldkamp et al. (see Simon, 1989) (B.K.Simon).

Types Species. M. laevis (Retz.) Kunth.

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

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