The grass genera of the world
~ Poa, e.g., with A. littoralis treated as a synonym of P. billardierei
Type species: Type: A. littoralis (Labill.) E.B.Alexeev.
Including Schedonorus Beauv.
Excluding Festucella, Hookerochloa
Habit, vegetative morphology. Perennial; rhizomatous and caespitose. Culms 30–80 cm high; herbaceous; unbranched above. Culm nodes exposed, or hidden by leaf sheaths; glabrous. Culm internodes hollow. Plants unarmed. Young shoots intravaginal. Leaves mostly basal; auriculate (occasionally, slightly), or non-auriculate. Sheaths terete. Leaf blades linear; apically flat; narrow (cylindrical); 0.6–1.7 mm wide (8–50 cm long); involute, subulate, rigid; without cross venation; persistent; rolled in bud. Ligule an unfringed membrane; truncate, or not truncate; 0.8–2.1 mm long (basal leaves), or 3.8–5.5 mm long (culm leaves). Contra-ligule absent.
Reproductive organization. Plants bisexual, all with bisexual spikelets; with hermaphrodite florets.
Inflorescence. Inflorescence paniculate; contracted; spicate. 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; pedicellate.
Female-fertile spikelets. Spikelets 9–17 mm long; compressed laterally; disarticulating above the glumes; disarticulating between the florets. Rachilla prolonged beyond the uppermost female-fertile floret; hairy; the rachilla extension with incomplete florets. Hairy callus present, or absent. Callus short; blunt (truncate, glabrous, scabrous or villous).
Glumes two; more or less equal; shorter than the spikelets to about equalling the spikelets; long relative to the adjacent lemmas; hairless; pointed; awnless; carinate; similar (membranous to chartaceous). Lower glume 3 nerved, or 5 nerved (only at the base). Upper glume 3 nerved, or 5 nerved (only at the base). Spikelets with incomplete florets. The incomplete florets distal to the female-fertile florets. The distal incomplete florets merely underdeveloped.
Female-fertile florets 3–5. Lemmas similar in texture to the glumes to decidedly firmer than the glumes (membranous to leathery); not becoming indurated; entire, or incised; not deeply cleft (no more than emarginate); awnless (muticous); hairless; carinate; without a germination flap; 5 nerved, or 7 nerved. Palea present; relatively long; apically notched; awnless, without apical setae; textured like the lemma; not indurated; 2-nerved; 2-keeled. Palea back scabrous, or hairy. Palea keels wingless; hairy. Lodicules present; 2; free; membranous; usually ciliate; toothed. Stamens 3. Anthers (3.8–)4.2–7.2 mm long; not penicillate. Ovary apically glabrous. Styles free to their bases. Stigmas 2; white.
Fruit, embryo and seedling. Fruit free from both lemma and palea; small (2.6–3.8 mm long); ventrally longitudinally grooved; compressed dorsiventrally (ventrally). Hilum short (usually oval, rarely punctiform). Embryo small; not waisted. Endosperm hard.
Abaxial leaf blade epidermis. Costal/intercostal zonation lacking. Papillae absent. Long-cells similar in shape costally and intercostally; of similar wall thickness costally and intercostally (walls thick and sinuous). Mid-intercostal long-cells fusiform (slightly); having markedly sinuous walls. Microhairs absent. Stomata absent or very rare. Intercostal short-cells common; not paired; silicified, or not silicified. Costal short-cells neither distinctly grouped into long rows nor predominantly paired. Costal silica bodies absent, or poorly developed; tall-and-narrow.
Transverse section of leaf blade, physiology. C3; XyMS+. Mesophyll with non-radiate chlorenchyma. Leaf blade adaxially flat. Midrib conspicuous (in a small, central rib); with one bundle only. Bulliforms not present in discrete, regular adaxial groups (with indistinct hinges only). All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present; forming figures. Sclerenchyma not all bundle-associated. The extra sclerenchyma in a continuous abaxial layer.
Special diagnostic feature. Female-fertile lemma not as in Lombardochloa (q.v.).
Classification. Watson & Dallwitz (1994): Pooideae; Poodae; Poeae. Soreng et al. (2015): Pooideae; Poinae. 2 species.
Distribution, phytogeography, ecology. Extra-tropical Australasia.
Xerophytic; species of open habitats; halophytic. F. littoralis and F. pubinervis are conspicous littoral sand and fore-dunes species.
References, etc. Morphological/taxonomic: see Jacobs (1990), Telopea 3, 601–603 for comments on Austrofestuca/Festucella/Hookerochloa. Leaf anatomical: this project.
Special comments. Clearly distinct from Festuca, but see Festucella, Hookerochloa. Illustrations. • A. littoralis: Gardner, 1952. • A. littoralis, abaxial epidermis of leaf blade: this project
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, and classifications. See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., Macfarlane, T.D., and Dallwitz, M.J. 1992 onwards. The 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. Version: 13th November 2017. delta-intkey.com/grass’.