Digitaria porrecta

Digitaria porrecta S. T. Blake. Proc. Roy. Soc. Queensland 84 :63 (1973).

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

Type of Basionym or Protologue Information: HT: Blake 23590, 12 Apr 1970, Australia: Queensland: Darling Downs, Cambooya, -27.5 S Lat, 151.45 E Long., 430 m (BRI; IT: CANB, L).

Recent synonyms: D. coenicola var. ramosa.

Key references (books and floras): [2002] D.Sharp & B.K.Simon, AusGrass, Grasses of Australia, [2008] S.W.L.Jacobs, R.D.B.Walley & D.J.B.Wheeler, Grasses of New South Wales (220).

Illustrations: [2008] S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th edn (220).

Habit. Perennial. Rhizomes present, elongated. Stolons absent. Culms erect, 40–70 cm tall, 4–7 -noded. Mid-culm internodes glabrous. Mid-culm nodes glabrous. Lateral branches sparsely branched. Leaf-sheaths smooth or antrorsely scabrous, glabrous on surface. Leaf-sheath auricles present. Ligule an eciliate membrane, 2.2–3 mm long, erose, obtuse. Leaf-blades flat, 6–15 cm long, 2.8–4 mm wide. Leaf-blade surface smooth, glabrous or indumented.

Inflorescence. Inflorescence compound, a panicle of racemes. Racemes 2–3, spreading, 12–27 cm long, bearing 10–20 fertile spikelets on each. Central inflorescence axis 8–12 cm long.

Spikelets. Spikelets pedicelled, 1–2 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, elliptic, dorsally compressed, 5.2–6.9 mm long. Rhachilla internodes elongated between glumes.

Glumes. Glumes thinner than fertile lemma. Lower glume oblong, membranous, 0 -nerved. Upper glume lanceolate or elliptic, 4.6–6.5 mm long, membranous, without keels, 5 -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 4.5–5.5 mm long, without keel. Lemma apex muticous. Lodicules present.

Continental Distribution: Australasia.

Australian Distribution: Queensland, New South Wales.

Queensland: Leichhardt, Darling Downs. New South Wales: North-Western Slopes.

Notes. Closely related to D. coenicloa and D. divaricatissima. The rebranching inflorescence illustrates the transition between Digitaria and Leptoloma.

In tropical and subtropical rain forests and tropical and subtropical sub-humid woodlands. Flowers Feb.-July.

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