The grass genera of the world
Type species: Type: N. microdon (Benth.) Domin.
Habit, vegetative morphology. Perennial; caespitose. Culms 30–50 cm high; herbaceous; unbranched above; 3 noded. Culm nodes exposed; glabrous. Young shoots extravaginal. Leaves mostly basal; non-auriculate. Leaf blades linear-lanceolate; narrow; 2–3 mm wide; flat, or rolled (inrolled); without cross venation; persistent. Ligule a rim of minute papillae; 0.1–1 mm long.
Reproductive organization. Plants bisexual, all with bisexual spikelets; with hermaphrodite florets. Not viviparous.
Inflorescence. Inflorescence few spikeleted (5–10); paniculate (short); open; with capillary branchlets; espatheate; not comprising partial inflorescences and foliar organs. Spikelet-bearing axes persistent. Spikelets not secund; pedicellate.
Female-fertile spikelets. Spikelets 18–21 mm long; subcylindrical; green; compressed laterally; disarticulating above the glumes; disarticulating between the florets; with conventional internode spacings. Rachilla prolonged beyond the uppermost female-fertile floret, or terminated by a female-fertile floret; the rachilla extension (when present) with incomplete florets. Hairy callus present. The callus hairs white. Callus short; blunt.
Glumes present; two; very unequal; shorter than the spikelets; (the longer) shorter than the adjacent lemmas; hairless; glabrous; pointed (acute); awnless; carinate. Lower glume 3 nerved. Upper glume 5 nerved. Spikelets with female-fertile florets only, or with incomplete florets. The incomplete florets distal to the female-fertile florets.
Female-fertile florets 7–14. Lemmas similar in texture to the glumes (thinly leathery); not becoming indurated; incised; 3 lobed; not deeply cleft (shortly 3-toothed); mucronate (the teeth with minute terminal mucros); hairless; glabrous; non-carinate; 5–7 nerved (and ridged). Palea present; relatively long; apically notched; awnless, without apical setae; thinner than the lemma; not indurated; 2-nerved; 2-keeled. Palea back glabrous. Palea keels wingless; scabrous. Lodicules present; 2; free; fleshy; ciliate (sparse), or glabrous; not or scarcely vascularized. Stamens 3. Anthers 2.8–3.5 mm long. Ovary apically glabrous. Styles free to their bases; free. Style bases adjacent. Stigmas 2.
Fruit, embryo and seedling. Disseminule a caryopsis enclosed in but free of the lemma and palea. Fruit free from both lemma and palea; small; golden-brown; narrowly obovate; not grooved; compressed dorsiventrally; glabrous; smooth. Hilum long-linear. Pericarp thin; fused. Embryo small (exactly one-third of caryopsis length); waisted.
Abaxial leaf blade epidermis. Costal/intercostal zonation conspicuous to lacking. Papillae absent. Long-cells similar in shape costally and intercostally; of similar wall thickness costally and intercostally. Mid-intercostal long-cells fusiform; having markedly sinuous walls. Microhairs present; panicoid-type; (75–)78–99(–111) microns long; (15–)20.4–21.6(–24) microns wide at the septum. Microhair total length/width at septum 3.75–5.1. Microhair apical cells (34.5–)36–42(–60) microns long. Microhair apical cell/total length ratio 0.42–0.54. Stomata absent or very rare; 38.4–43 microns long. Subsidiaries parallel-sided. Guard-cells overlapping to flush with the interstomatals. Intercostal short-cells common; not paired (solitary); not silicified. Costal short-cells neither distinctly grouped into long rows nor predominantly paired. Costal silica bodies tall-and-narrow (a few), or crescentic; not sharp-pointed.
Transverse section of leaf blade, physiology. C3; XyMS+. Mesophyll with non-radiate chlorenchyma; without adaxial palisade. Leaf blade nodular in section; with the ribs very irregular in sizes. Midrib conspicuous (by virtue of large hinge groups); with one bundle only. Bulliforms present in discrete, regular adaxial groups; in simple fans (in addition to the large hinges). All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present; forming figures. Sclerenchyma all associated with vascular bundles.
Classification. Watson & Dallwitz (1994): Arundinoideae; Danthonieae. Soreng et al. (2015): Danthonioideae; Danthonieae. 1 species (N. microdon).
Distribution, phytogeography, ecology. Australia.
Helophytic; glycophytic (upland swamps).
References, etc. Leaf anatomical: studied by us.
Illustrations. • N. microdon, abaxial epidermis of leaf blade with microhair: this project. Notochloe microdon, with a panicoid type microhair detectable (at lower left). • N. microdon, abaxial leaf blade epidermal microhair: 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: 11th December 2017. delta-intkey.com/grass’.