Grass Genera of the World

L. Watson and M. J. Dallwitz


Fasciculochloa B.K. Simon & C.M. Weiller

From the Latin fasciculus (a small bundle), in reference to the fasciculate spikelets on the mature panicle branches.

Habit, vegetative morphology. Perennial; caespitose. Culms about 40–70 cm high; herbaceous; sparingly branched above; 3–4 noded. Culm nodes exposed; glabrous. Culm leaves present. Upper culm leaf blades fully developed. Culm internodes solid. Young shoots intravaginal. Leaves not basally aggregated; non-auriculate. Leaf blades linear; narrow; to 3.5 mm wide; flat; parallel veined; without cross venation; persistent; a fringed membrane; truncate; to 0.4 mm long. Contra-ligule absent.

Reproductive organization. Plants bisexual, with bisexual spikelets; with hermaphrodite florets. The spikelets hermaphrodite.

Inflorescence. Inflorescence paniculate (fully exserted when mature, the spikelets fasciculate towards the ends of the branches); open. Inflorescence with axes ending in spikelets. Inflorescence espatheate; not comprising ‘partial inflorescences’ and foliar organs. Spikelet-bearing axes spikes. Spikelets obscurely paired, or solitary; not secund; pedicellate. Pedicel apices cupuliform. Spikelets imbricate.

Female-fertile spikelets. Spikelets to 2.5 mm long; obscurely adaxial; compressed laterally to not noticeably compressed; falling with the glumes; not disarticulating between the florets; with conventional internode spacings. The upper floret not stipitate. Rachilla terminated by a female-fertile floret; hairless. Hairy callus absent.

Glumes two; very unequal; shorter than the spikelets to about equalling the spikelets (the upper slightly shorter than the spikelet, the lower about half as long); shorter than the adjacent lemmas; hairless; glabrous; pointed to not pointed; awnless; non-carinate. Lower glume 0.6 times the length of the upper glume; much shorter than half length of lowest lemma; 3 nerved. Upper glume not saccate; 3–5 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; becoming hardened. The proximal incomplete florets sterile. The proximal lemmas awnless; 5 nerved; more or less equalling the female-fertile lemmas to decidedly exceeding the female-fertile lemmas; similar in texture to the female-fertile lemmas (membranous); not becoming indurated.

Female-fertile florets 1. Lemmas elliptic; not saccate; similar in texture to the glumes (chartaceous); smooth; not becoming indurated; entire; pointed (acute); not crested; awnless; hairless; non-carinate; having the margins lying flat on the palea; without a germination flap (?); obscurely 2 nerved. Palea present; relatively long; tightly clasped by the lemma; entire; awnless, without apical setae; textured like the lemma; not indurated. Palea back glabrous. Lodicules present; 2; seemingly basally joined; glabrous; not or scarcely vascularized. Stamens 2. Anthers about 0.75 mm long; not penicillate; without an apically prolonged connective. Ovary glabrous. Styles free to their bases; free. Stigmas 2.

Fruit, embryo and seedling. Disseminule a free caryopsis. Fruit small (about 2.2 mm long); not grooved; glabrous. Hilum short (about 5% of the fruit length). Embryo large (about 30% of the fruit length); waisted. Endosperm hard.

Abaxial leaf blade epidermis. Costal/intercostal zonation conspicuous. Papillae absent. Long-cells similar in shape costally and intercostally; of similar wall thickness costally and intercostally. Intercostal zones with typical long-cells. Mid-intercostal long-cells rectangular; having markedly sinuous walls. Microhairs present; elongated; clearly two-celled; panicoid-type. Microhair apical cell wall thinner than that of the basal cell and often collapsed. Microhairs 51–69 microns long; 6 microns wide at the septum. Microhair apical cells 27–30 microns long. Stomata common; 18–27 microns long. Subsidiaries non-papillate; dome-shaped; not including both parallel-sided and triangular forms on the same leaf. Guard-cells overlapping to flush with the interstomatals. Intercostal short-cells fairly common; not paired (solitary); not silicified. Intercostal silica bodies absent. Intercostal prickles present, macrohairs absent. Crown cells absent. Costal short-cells conspicuously in long rows. Costal silica bodies present and well developed; ‘panicoid-type’; dumb-bell shaped.

Transverse section of leaf blade, physiology. C3; XyMS+. Mesophyll with non-radiate chlorenchyma; without adaxial palisade; not Isachne-type; not traversed by colourless columns. Leaf blade ‘nodular’ in section to adaxially flat; with the ribs more or less constant in size. Midrib not readily distinguishable; with one bundle only; without colourless mesophyll adaxially. Bulliforms present in discrete, regular adaxial groups; in simple fans. All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present; forming ‘figures’ to nowhere forming ‘figures’ (some slight ‘anchors’). Sclerenchyma all associated with vascular bundles.

Taxonomy. Panicoideae; Panicodae; Paniceae.

Distribution, ecology, phytogeography. 1 species; Southeast Queensland. Helophytic to mesophytic; glycophytic.

Australian. Tropical North and East Australian.

References, etc. Morphological/taxonomic: Simon and Weiller (1995). Leaf anatomical: Simon and Weiller (1995).

Illustrations. • Abaxial epidermis of leaf blade


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