Thellungia Bull. Misc. Inform. Kew 1920: 97 (1920).

Derivation:. Named for Swiss botanist Albert Thellung, 1881–1928.

Taxonomic revisions, nomenclatural references:. M.Lazarides, Aust. Syst. Bot.10: 95–96 (1996) as Eragrostis

Key references (keys and floras):. M.Lazarides, Flora of Central Australia 4463 (1981); J.C.Tothill and J.B.Hacker, Grasses of Southern Queensland 400–401 (1983); B.K.Simon, Key to Australian Grasses 168 (1993); S.W.L.Jacobs and K.L.McClay, Flora of New South Wales 4: 533–534 (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, 381–382 (2008).

W.D.Clayton & S.A.Renvoize, Genera Graminum (1986), genus (syn. of Eragrostis).

Native, endemic. 1 species. NT, Qld, and NSW.

Habit. Robust perennial, tufted. Leaf blades narrow. Ligule a fringe of hairs.

Inflorescence. Inflorescence paniculate, a spike-like panicle, contracted (the primary branches short, erect-appressed).

Spikelets. Spikelets laterally compressed, more than 2 flowered, with 2 or more fertile florets, solitary, subsessile; with naked rachilla extension, or with rachilla terminating in a floret (all the florets hermaphrodite?). Fertile spikelets disarticulating above glumes.

Glumes. Glumes unequal, shorter than adjacent lemmas, pointed, awnless, similar (membranous, narrow). Lower glume 1 nerved. Upper glume 1 nerved.

Florets. Fertile florets (1–)3–5. Lemmas similar in texture to glumes (membranous), not becoming indurated, entire at apex, pointed, muticous, 1 nerved, glabrous, 1 keeled. Keel wingless. Palea conspicuous and relatively short (about one half the lemma length), entire (pointed), 2 nerved. Stamens 3. Grain small, compressed laterally. Hilum short. Embryo large.

Kranz Anatomy. C4.

Classification. Chloridoideae; Cynodonteae.

Notes. Placed in synonymy with Eragrostis by Clayton and Renvoize (1986) and Lazarides (1996). The spikelet is morphologically intemediate between Eragrostis and Sporobolus and the genus deserves recognition at generic rank, if the latter two genera are maintained as separate entities (B.K.Simon).

Types Species. T. advena Stapf ex Probst.

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

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