Amphibromus whitei C.E.Hubb.,
Kew Bull. 1941: 30 (1941).
Amphibromus whitei C.E.Hubb.,
Kew Bull. 1941: 30 (1941).
T: Maranoa District; Roma, on edge of large fresh-water swamp, Qld, 25 Oct 1933, White 9580; holo: K, n.v., iso: BRI.
Vegetative form. Perennial, caespitose. Leaves scattered along the culms. Culms 27-33 cm high, unbranched above, 2-3 noded. Mid-culm nodes glabrous, exposed, not pigmented, constricted. Mid-culm internodes glabrous, terete. Young shoots intravaginal. Leaves non-auriculate. Basal leaf sheaths not keeled, terete, glabrous (the base of the basal sheaths retrorsely densely hairy with c. golden hairs), with the veins equally striate, with margins free, membranous, smooth. Ligule 4-8 mm long, not lobed, decurrent, hyaline to membranous, smooth, long acute, entire. Collar glabrous. Leaf blades joining the sheath gradually, flat to involute, linear, to 145 mm long, 1-1.5 mm wide; adaxially scabrous (on the veins), channelled; abaxially glabrous (epidermal cells conspicuous), with midrib prominent; with margins smooth, apices blunt and rounded, hooded. Prophyll 10 mm long, pubescent (on the keels, and retrorsely hairy on surfaces).
Reproductive organization. Plants bisexual. Rudimentary spikelets absent. Incomplete spikelets absent. Inflorescence of cleistogamous spikelets. Cleistogamous spikelets on the exserted inflorescence (?).
Inflorescence. Inflorescence a panicle, pallid to green, erect, contracted, to 20 mm wide, oblong (i.e. linear), symmetrical, partially exserted. Main inflorescence axis 60-125 mm long. Rachides but most of length, strap-like, scabrous. Rachis angles scabrous. Pulvini absent. Primary inflorescence branches scabrous; paired, branching at the base or not branched at the base, spreading, distichous, without spikelets inserted at the base. Spikelets 1-3 on a typical ultimate inflorescence branch, distichous, on first order branches to on second order branches, erect, spreading, subtending foliar structure absent.
Hermaphrodite (`perfect') spikelets. Hermaphrodite spikelets pedicellate, 6-10 mm long, 2 mm wide, laterally compressed, obovate, not disarticulating as a separate unit, disarticulating above the glumes. Pedicels 1-8 mm long, erect, thick, scabrous, straight. Glumes two per spikelet, dissimilar, subequal, shorter than the florets (1/3-1/4), approximately half the proximal lemma in length. Lower glume c. 2/3s the length of the upper glume, narrowly ovate, 1.5-2.3 mm long, 0.3-0.5 mm wide, hyaline, slightly keeled, obtuse, entire, muticous, margin smooth; 3 veined (the laterals short), veins obscure, midvein glabrous; intercostal regions glabrous. Upper glume narrowly ovate, 2.3-3 mm long, 0.5-0.8 mm wide, hyaline, slightly keeled, acute to obtuse, entire, muticous, margin smooth; 3 veined (the laterals short), veins prominent, midvein glabrous; intercostal regions glabrous. Rudimentary florets distal to the hermaphrodite florets. Incomplete florets absent (? or are terminal florets female). Hermaphrodite florets 4-5 per spikelet. Rachilla disarticulating between the florets, disarticulating directly below the florets, straight, segments 0.9-1.5 mm long, puberulous, elongated between all florets, apically prolonged; prolongation 1 mm long, terminated by a rudimentary floret (a very reduced structure). Callus present, blunt, 0.1-0.15 mm long, villous (? the hairs straight, white and c. silky, on the sides to front), hairs 0.5 mm long. Lemma decidedly firmer than the glumes, laterally compressed, elliptic, 3-4 mm long, 0.7-1 mm wide, membranous, slightly keeled (?), obtuse, bidentate (? i.e. lobed), 2 -lobed; apex hyaline; awned. Lemma margins ciliolate. Lemma 7 veined. Lemma veins not confluent apically (and not extending to the margins), prominent, scabrous, with the hairs on all the veins, with the hairs only at the vein base (the lower half); intercostal regions scabrous (and c. tubercled), the hairs only at the base. Awns 1, median. Median awn much longer than the body of the lemmas, 11-14 mm long, 1 veined, terete (?), dorsal, arising from the upper half of the lemma, c. geniculate, c. column twisted, scabrous. Palea fully developed, slightly shorter than the lemmas, thinner than the lemmas, tightly clasped by the lemmas, narrowly obovate, 3.4 mm long, 0.5 mm wide, hyaline, 2-keeled, keels winged, acute, shortly bifid, margin ciliolate (distally, hairs sparse); 2 veined, proximally veins scabrous and veins ciliolate (distally); intercostal regions glabrous. Lodicules 2, free, hyaline, oblong, acute, smooth, with entire margins, glabrous. Stamens 3. Anthers yellow, entire or shortly basally 2-lobed. Cleistogamous anthers 0.23-0.26 mm long. Ovary glabrous. Styles 2, apical, free to their bases.
Fruit. Fruit mature caryopsis not seen free from both lemma and palea, pale yellow-brown, oblong (?), laterally compressed, 1.3 mm long, 0.4 mm wide, not grooved, glabrous. Hilum 0.4 mm long (c. 1/3 the fruit), linear, above the base (?). Embryo 0.3 mm long, not waisted.
Distribution. Queensland.
References. Morphology: Jacobs & Lapinpuro (1986).
Cite this publication as:
C.M. Weiller, M.J.
Henwood, J. Lenz and L. Watson (1995 onwards). `Pooideae (Poaceae) in
Australia - Descriptions and Illustrations'. URL
http://muse.bio.cornell.edu/delta/
Dallwitz
(1980) and Dallwitz, Paine and Zurcher (1993)
should also be cited.