Digitaria imbricata

Digitaria imbricata R.D. Webster. Brunonia 6: 184 (1983).

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

Type of Basionym or Protologue Information: Australia: Queensland: North Kennedy District: 2 Feb 1931, Hubbard & Winders 7103 (HT: BRI; IT: CANB).

Key references (books and floras): [2002] D.Sharp & B.K.Simon, AusGrass, Grasses of Australia.

Habit. Perennial. Rhizomes present, elongated. Stolons absent. Culms erect, 30–60 cm tall, 3–5 -noded. Mid-culm internodes glabrous. Mid-culm nodes bearded. Lateral branches sparsely branched. Leaf-sheaths antrorsely scabrous, glabrous on surface or hairy. Leaf-sheath auricles absent. Ligule an eciliate membrane, 0.3–1.1 mm long, erose, obtuse. Leaf-blades flat or conduplicate, 2–7.5 cm long, 2.4–3.1 mm wide. Leaf-blade surface scabrous, glabrous or indumented.

Inflorescence. Inflorescence subdigitate, with racemose branches. Racemes 3–4, spreading, 3–6.5 cm long, bearing 20–34 fertile spikelets on each. Central inflorescence axis 1.5–4 cm long.

Spikelets. Spikelets pedicelled, 2 in the cluster. 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, lanceolate, dorsally compressed, 2.4–2.8 mm long. Rhachilla internodes brief up to lowest fertile floret.

Glumes. Glumes thinner than fertile lemma. Lower glume ovate, membranous. Upper glume lanceolate, 2.3–2.7 mm long, membranous, without keels, 3 -nerved. Upper glume surface indumented. Florets. Basal sterile florets 1, barren, without significant palea. Lemma of lower sterile floret 100 % of length of spikelet, membranous, 7 -nerved.

Fertile lemma 2.3–2.6 mm long, without keel. Lemma apex muticous or mucronate.

Continental Distribution: Australasia.

Australian Distribution: Queensland.

Queensland: Mitchell, North Kennedy.

Notes. Similar to D. hubbardii but lacking the transverse line of pubescence on the lower lemma.

Native. Presently known from several collections in the North Kennedy and Mitchell Districts of Qld. Qld. In tropical and subtropical sub-humid woodlands and semi-arid shrub woodlands. Flowers Jan.-Feb.

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