Grass Genera of the World

L. Watson and M. J. Dallwitz


Cliffordiochloa B.K Simon

From the Greek chloa (grass), and for H.T.Clifford (Australian botanist).

Habit, vegetative morphology. Weak perennial; caespitose. Culms 60–80 cm high; herbaceous; branched above; 4–6 noded. Culm nodes exposed. The shoots not aromatic. Leaves not basally aggregated. Sheaths compressed. Leaf blades linear; narrow; 2–3 mm wide; flat; an unfringed membrane, or a fringed membrane; 0.5 mm long.

Reproductive organization. Plants bisexual, with bisexual spikelets; with hermaphrodite florets. The spikelets all alike in sexuality; hermaphrodite.

Inflorescence. Inflorescence of spicate main branches (the main axis 10–20 cm long, the branches spreading, not whorled); non-digitate. Primary inflorescence branches inserted all around the main axis. Inflorescence with axes ending in spikelets. Inflorescence espatheate. The racemes spikelet bearing to the base. Spikelet-bearing axes persistent. Spikelets unaccompanied by bractiform involucres, not associated with setiform vestigial branches; paired (mostly), or in triplets (a few); secund (on one side of the branch); from two sides of the three-sided rachis; pedicellate (the pedicels 0.5–1.5 mm long). Pedicel apices cupuliform. Spikelets consistently in ‘long-and-short’ combinations; unequally pedicellate in each combination. The ‘shorter’ spikelets hermaphrodite. The ‘longer’ spikelets hermaphrodite.

Female-fertile spikelets. Spikelets 1.5 mm long; elliptic; adaxial; compressed laterally; falling with the glumes; with conventional internode spacings. The upper floret not stipitate. Rachilla terminated by a female-fertile floret. Hairy callus absent. Callus absent.

Glumes two; very unequal; (the upper) about equalling the spikelets (the lower about half as long); (the upper) long relative to the adjacent lemmas (about equalling the L1); hairless; glabrous, or scabrous (on the keel); pointed (the lower), or not pointed (the upper notched); awnless; carinate (the lower strongly keeled, the upper only slightly so); very dissimilar (membranous, the lower deltoid and almost keel-winged above, the upper less strongly keeled and slightly notched). Lower glume about 0.5 times the length of the upper glume; shorter than the lowest lemma; longer than half length of lowest lemma; 1 nerved. Upper glume not saccate; 3 nerved, or 5 nerved. Spikelets with incomplete florets. The incomplete florets proximal to the female-fertile florets. Spikelets with proximal incomplete florets. The proximal incomplete florets 1; paleate. Palea of the proximal incomplete florets fully developed (2-keeled, hyaline); not becoming conspicuously hardened and enlarged laterally. The proximal incomplete florets sterile. The proximal lemmas resembling the upper glume in shape, size and texture; awnless; 3 nerved, or 5 nerved; more or less equalling the female-fertile lemmas to decidedly exceeding the female-fertile lemmas (slightly exceeding it); somewhat less firm than the female-fertile lemmas (membranous, like the glumes); not becoming indurated.

Female-fertile florets 1. Lemmas elliptic; not saccate; thin, but decidedly firmer than the glumes; striate; not becoming indurated (thinly cartilaginous); white in fruit; entire; blunt; not crested; awnless; hairless; glabrous; non-carinate; having the margins inrolled against the palea; seemingly without a germination flap; 0 nerved. Palea present; relatively long; tightly clasped by the lemma; entire; awnless, without apical setae; textured like the lemma; 2-nerved; keel-less. Palea back glabrous. Lodicules present; 2; fleshy; glabrous; not or scarcely vascularized. Stamens 2. Anthers not penicillate; without an apically prolonged connective. Ovary glabrous. Stigmas 2.

Abaxial leaf blade epidermis. Costal/intercostal zonation conspicuous. Papillae absent. Long-cells markedly different in shape costally and intercostally (the costals much narrower); of similar wall thickness costally and intercostally (walls of medium thickness). Intercostal zones with typical long-cells. Mid-intercostal long-cells rectangular; having markedly sinuous walls. Microhairs present; elongated; clearly two-celled; panicoid-type; 40–50 microns long; 7–10 microns wide at the septum. Microhair total length/width at septum 4–6. Microhair apical cells 25–30 microns long. Microhair apical cell/total length ratio 0.4–0.6. Stomata common; 20–30 microns long. Subsidiaries non-papillate; low dome-shaped to triangular, or parallel-sided (by extreme truncation of triangles); including both triangular and parallel-sided forms on the same leaf. Guard-cells overlapping to flush with the interstomatals. Intercostal short-cells common; in cork/silica-cell pairs and not paired (many solitary); silicified and not silicified. Intercostal silica bodies mostly cross-shaped. Crown cells absent. Costal short-cells conspicuously in long rows. Costal silica bodies present and well developed; ‘panicoid-type’; nearly all dumb-bell shaped.

Transverse section of leaf blade, physiology. C3; XyMS+. Mesophyll with radiate chlorenchyma; Isachne-type; without ‘circular cells’; not traversed by colourless columns; without arm cells; without fusoids. Midrib conspicuous; with one bundle only, or having complex vascularization (depending on interpretation of the midrib). The lamina symmetrical on either side of the midrib. Bulliforms present in discrete, regular adaxial groups; in simple fans (these large). All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present (with all the primary bundles, the minor bundles mostly with adaxial and abaxial strands). Sclerenchyma all associated with vascular bundles.

Taxonomy. Panicoideae; Panicodae; Paniceae.

Distribution, ecology, phytogeography. 1 species; Queensland. Helophytic.

Australian. North and East Australian. Tropical North and East Australian.

References, etc. Morphological/taxonomic: B.K. Simon 1992. Leaf anatomical: this project.

Special comments. Fruit data wanting.

Illustrations. • general aspect and spikelet details. • Inflorescence. Cliffordiochloa parvispicula. • Inflorescence detail. Cliffordiochloa parvispicula. • Spikelets. Cliffordiochloa parvispicula. • Spikelets. Cliffordiochloa parvispicula. • Abaxial epidermis of leaf blade. Cliffordiochloa parvispicula.


Cite this publication as: Watson, L., and Dallwitz, M. J. (1992 onwards). ‘Grass Genera of the World: Descriptions, Illustrations, Identification, and Information Retrieval; including Synonyms, Morphology, Anatomy, Physiology, Phytochemistry, Cytology, Classification, Pathogens, World and Local Distribution, and References.’ http://biodiversity.uno.edu/delta/. Version: 18th August 1999. Dallwitz (1980), Dallwitz, Paine and Zurcher (1993 onwards, 1998), and Watson and Dallwitz (1994), and Watson, Dallwitz, and Johnston (1986) should also be cited (see References).

Index