Homopholis C.E. Hubb.
Habit, vegetative morphology. Perennial; stoloniferous (often), or caespitose. Culms 20–50 cm high; herbaceous. Culm nodes glabrous. Culm internodes hollow. Leaves not basally aggregated; non-auriculate. Leaf blades narrow; 2–2.5 mm wide; without cross venation; persistent; rolled in bud; an unfringed membrane; truncate; 1.5 mm long.
Reproductive organization. Plants bisexual, with bisexual spikelets; with hermaphrodite florets.
Inflorescence. Inflorescence paniculate; open (up to 25 cm long, the branches to 15 cm with one or few spikelets towards their ends); with capillary branchlets. Primary inflorescence branches inserted all around the main axis. Inflorescence espatheate; not comprising ‘partial inflorescences’ and foliar organs. Spikelet-bearing axes persistent. Spikelets not secund. Pedicel apices cupuliform.
Female-fertile spikelets. Spikelets 4.5–6 mm long; lanceolate; compressed dorsiventrally; falling with the glumes. Rachilla terminated by a female-fertile floret. Hairy callus absent.
Glumes two; more or less equal (the G1 slightly longer); long relative to the adjacent lemmas; pointed; awnless; very dissimilar to similar (the upper shortly hairy on the back). Lower glume 3–7 nerved. Upper glume 7 nerved, or 9 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, or epaleate. Palea of the proximal incomplete florets (when present) reduced (nerveless). The proximal incomplete florets sterile. The proximal lemmas similar to G2; awnless; 7 nerved, or 9 nerved; decidedly exceeding the female-fertile lemmas; less firm than the female-fertile lemmas; not becoming indurated.
Female-fertile florets 1. Lemmas about half the spikelet length, shortly beaked; decidedly firmer than the glumes; smooth; becoming indurated (slightly so, and shiny); yellow in fruit; entire; pointed; awnless (but rostrate); hairless; non-carinate (rounded on the back); having the margins lying flat on the palea; with a clear germination flap; 5–7 nerved. Palea present (shortly auriculate at the base); relatively long; entire; awnless, without apical setae; thinner than the lemma (membranous); not indurated; 2-nerved. Lodicules present; 2; free; fleshy; glabrous. Stamens 3. Anthers 1.5 mm long; not penicillate. Ovary glabrous. Styles free to their bases. Stigmas 2; red pigmented.
Fruit, embryo and seedling. Fruit small; compressed dorsiventrally. Hilum short. Embryo large.
Abaxial leaf blade epidermis. Papillae absent (except on the subsidiaries). Mid-intercostal long-cells having markedly sinuous walls. Microhairs present; panicoid-type; 33–39 microns long; 13–17.4 microns wide at the septum. Microhair total length/width at septum 5–6.1. Microhair apical cells 5.4–7.2 microns long. Microhair apical cell/total length ratio 0.39–0.45. Stomata common; 29–33 microns long. Subsidiaries papillate; triangular. Costal silica bodies ‘panicoid-type’.
Transverse section of leaf blade, physiology. C3; XyMS+. Mesophyll with radiate chlorenchyma. Leaf blade ‘nodular’ in section; with the ribs more or less constant in size. Midrib not readily distinguishable; with one bundle only. Bulliforms present in discrete, regular adaxial groups; in simple fans. All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present; forming ‘figures’. Sclerenchyma all associated with vascular bundles.
Taxonomy. Panicoideae; Panicodae; Paniceae.
Distribution, ecology, phytogeography. 3 species; Australia. Shade species; glycophytic. In forests.
Australian. North and East Australian. Tropical North and East Australian.
Economic importance. Important native pasture species: H. belsonii.
References, etc. Morphological/taxonomic: Hubbard 1934; Webster 1987. Leaf anatomical: this project.
Illustrations. • Abaxial epidermis of leaf blade. • Abaxial epidermis of leaf blade. • Transverse section 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).
