Digitaria setigera Roem. & Schult.
Annuals, with stems rooting at lower nodes, sprawling to form loose mats. Leaf-sheath folded, strongly ribbed, light green, with several long fine spreading tubercle-based hairs. Ligule (1)-1.5-2-(2.5) mm, membranous, glabrous, truncate, erose. Leaf-blade (3.5)-5.5-10 cm × 2-7 mm, soft, linear, usually with scattered fine hairs, sometimes glabrous, ribs and margins scabrid, tapering to long, finely pointed tip. Culm (10)-20-45 cm, ascending-erect or straggling, internodes glabrous. Racemes 3-5, (3.5)-5-9.5 cm, slender, digitate (on Kermadec Is plants normally remaining bunched together) rarely spreading; rachis 3-angled, winged, 0.3-0.8 mm wide, scabrid on wing margins and sometimes on central ridge; pedicels 3-angled, scabrid on angles, short-hairy at base. Spikelets 2.5-3.5 mm, in pairs, lanceolate, long-acute, laterally with fine acute-tipped hairs. Lower glume 0, or a minute rim or scale c. 0.1 mm, upper 0.6-1-(1.5) mm, c. ¼-(⅓) length of spikelet, 0-3-nerved, triangular, obtuse to subacute, glabrous, or with long hairs on margins overtopping glume. Lower floret: lemma = spikelet, (5)-7-nerved, nerves inaequidistant, glabrous, outer internerves with long hairs. Upper floret: lemma ≈ spikelet, glabrous, acuminate, yellowish or light brownish at maturity; palea ≈ lemma, similar in texture and shape; anthers 1-1.3 mm; stigmas brown; caryopsis c. 1.5 mm, oblong.
K. Waste places, bird colony areas, soil pockets among boulders at cliff bases.
Naturalised.
A raceme from a specimen at US, collected at Bay of Islands during the U.S. Exploring Expedition 1838-42 and determined by Dr Agnes Chase as Digitaria microbachne was sent by Dr Chase to Mr V. D. Zotov (CHR 97607). It agrees well with Kermadec Is specimens of D. setigera. The envelope containing the raceme is labelled "Z New Zealand" in Dr Chase's hand. No other specimens are known from the main islands of N.Z.
A variable species indigenous to and widespread in tropical Asia, Malesia, Pacific to French Polynesia and northern Australia; formerly widely referred to in Pacific treatments as D. pruriens (Trin.) Büse. Plants with very long racemes (11-22 cm) were also referred to D. microbachne (C.Presl) Henrard.