Dallwatsonia Austrobaileya 3: 678 (1992).
Derivation:. Named for Michael Dallwitz, formerly CSIRO Division of Entomology and Leslie Watson, formerly of RSBS, Australian National University.
Key references (keys and floras):. B.K.Simon, Key to Australian Grasses 90 (1993); D.Sharp and B.K.Simon, AusGrass (2002).
Native, endemic. 1 species, from tropical Queensland. Qld.
Habit. Perennial, single-stemmed. Leaf blades narrow. Ligule a fringed membrane.
Inflorescence. Inflorescence of spicate main branches or paniculate (the main axis to 22 cm long, the primary branches to 6 cm, the spikelet-bearing branches reduced to from 2 to several spikelets), an open panicle with branches ending in single spikelets, non-digitate.
Spikelets. Spikelets 2 flowered, with 1 fertile floret, unaccompanied by bractiform involucres, not associated with setiform vestigial branches, more or less paired, pedicelled (the pedicels 0.1–4 mm long). Fertile spikelets with lower incomplete floret(s), elliptic or lanceolate, adaxial (with lower glume against rachis), somewhat laterally compressed or subterete, falling with glumes.
Glumes. Glumes unequal (the lower much shorter), (the upper) about equal to spikelet (the lower about a third as long), shorter than adjacent lemmas, hairless, glabrous, pointed, awnless, non-keeled (but with raised nerves), dissimilar (membranous, the lower ovate and much shorter, the upper lanceolate and almost as long as the lower lemma). Lower glume 0.3–0.5 times length of upper glume, much shorter than half length of lowest lemma, convex on back, relatively smooth, 5 nerved. Upper glume 5–7 nerved.
Florets. Lower incomplete floret(s) sterile. Lemmas lanceloate, membranous, resembling the upper glume, awnless, 5 nerved, more or less equalling fertile lemmas to exceeding fertile lemmas, less firm than fertile lemmas to similar in texture to fertile lemmas, not becoming indurated. Fertile florets 1. Lemmas lanceolate, similar in texture to glumes to decidedly firmer than glumes (membranous to very thinly cartilaginous), smooth, not becoming indurated, white in fruit, entire at apex, pointed, muticous, with a clear germination flap, 5–7 nerved, with nerves non-confluent, glabrous, having flat margins not tucked into palea, not keeled. Palea relatively long, gaping, entire, textured like lemma, 2 nerved, not keeled, glabrous. Lodicules 2. Stamens 3.
Kranz Anatomy. C3.
Classification. Panicoideae; Paniceae.
Notes. A segregate from Panicum distinguished by a few distinctive characters, one of which (the adaxial lower glume) it shares with Alexfloydia, Cliffordiochloa and Steinchisma (B.K.Simon).
Types Species. D. felliana B.K.Simon.
Biogeographic Element. Clifford & Simon 1981, Simon & Jacobs 1990: Endemic.