Pogonatherum

Pogonatherum Essai Agrost. 56, 176 (1812).

Derivation:. From Greek pogon (beard) and ather (awn), referring to the hair like awns.

Key references (keys and floras):. E.E.Henty, Manual Grasses New Guinea 159 (1969); M.Lazarides, Tropical Grasses S.E. Asia 62–63 (1980); B.K.Simon, Key to Australian Grasses 152 (1993); D.Sharp and B.K.Simon, AusGrass (2002); S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th ed, 355 (2008).

W.D.Clayton & S.A.Renvoize, Genera Graminum (1986), genus (576).

Native. 3 species, from India to Japan, Australia. 1 species in Australia, Qld. Also New Guinea and Malesia.

Habit. Delicate perennial, tufted or decumbent. Culms woody and persistent. Leaf blades narrow. Ligule a fringed membrane.

Inflorescence. Inflorescence a single raceme (a solitary, spicate, pedunculate, axillary raceme), a single raceme or spike. Spikelet-bearing axes racemes, more or less with homomorphic spikelets (the pedicelled slightly smaller), solitary, disarticulating at joints.

Spikelets. Spikelets laterally compressed, 2 flowered, with 1 fertile floret, paired, sessile and pedicelled, in pedicelled/sessile combinations; sessile spikelet with lower incomplete floret, or without lower incomplete floret. Fertile spikelets falling with glumes (the pedicelled falling from its pedicel, the sessile falling with the internode and pedicel).

Glumes. Glumes more or less equal, long relative to adjacent lemmas, hairy or hairless, (the upper) awned (with a capillary awn from the mid-nerve), dissimilar (lower glume cartilaginous, rounded on the back and truncate, upper glume compressed-keeled and awned). Lower glume strongly convex on back, relatively smooth, 0–1 nerved. Upper glume 1 nerved.

Florets. Lower incomplete floret(s) male, or sterile. Lemmas 0 nerved or 1 nerved, not becoming indurated. Fertile florets 1. Lemmas less firm than glumes (thinly membranous to hyaline), not becoming indurated, incised, deeply cleft to not deeply cleft (to 1/3 to 1/2 its length), awned, 1 nerved, glabrous. Awns 1, from a sinus, geniculate, much longer than body of lemma (filiform). Palea nerveless. Callus blunt. Stamens 1–2. Grain small, compressed dorsiventrally (flattened on the front). Hilum short. Embryo large. Pedicelled spikelets present, similar in shape to sessile spikelet, female.

Kranz Anatomy. C4.

2n = 20.

Classification. Panicoideae; Andropogoneae.

Notes. A homogeneous genus, whose species are barely separable.(Clayton & Renvoize, 1986).

Types Species. P. saccharoideum P.Beauv. = P. paniceum (Lam.) Hack.

Biogeographic Element. Clifford & Simon 1981, Simon & Jacobs 1990: Indo-Malayan.

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