The grass genera of the world
~ Poa subgen. Andinae Nicora
Type species: Nicoraepoa andina (Trin.) Soreng & L. J. Gillespie.
Habit, vegetative morphology. Perennial; stoutly short- to long- rhizomatous (with basal leaves having sheaths becoming coarsely fibrous in age, smooth or sparsely scabrous between veins). Culms herbaceous. Young shoots extravaginal and intravaginal. Sheath margins joined (to about a quarter of the sheath length), or free (open almost to the base). Leaf blades pungent; broad to narrow; 2–15 mm wide; usually glabrous, rarely hispidulous flat, or folded, or rolled; without cross venation; persistent. Ligule firmly membranous to chartaceous, an unfringed membrane to a fringed membrane; truncate, or not truncate (sometimes longer at the sides); 0.2–3 mm long.
Reproductive organization. Plants monoecious with all the fertile spikelets unisexual, or bisexual, all with bisexual spikelets, or dioecious (dioecious, gynodioecious or monoecious); with hermaphrodite florets, or without hermaphrodite florets. The spikelets of sexually distinct forms on the same plant, or all alike in sexuality; on individual plants hermaphrodite, or female-only, or male-only, or sterile.
Inflorescence. Inflorescence paniculate; open, or contracted. Rachides smooth or scabrous, neither flattened nor hollowed, not winged. Inflorescence espatheate; not comprising partial inflorescences and foliar organs. Spikelets not secund; pedicellate (the pedicels glabrous, scabrous or rarely hispidulous).
Female-sterile spikelets. The male spikelets with glumes; without proximal incomplete florets; 2–5 floreted (?). The lemmas awnless to awned. Male florets 3 staminate.
Female-fertile spikelets. Spikelets compressed laterally; disarticulating above the glumes; disarticulating between the florets. Rachilla presumably prolonged beyond the uppermost female-fertile floret (?!); the rachilla extension with incomplete florets, or naked (?!). Hairy callus present (with a crown of 0.2–3 mm long hairs), or absent. Callus blunt.
Glumes two; more or less equal (subequal); shorter than the spikelets; long relative to the adjacent lemmas (subequal to them); hairless; glabrous, or scabrous (on the keels); awnless; carinate; chartaceous or apically scarious, similar. Lower glume about equalling the lowest lemma; 1 nerved, or 3 nerved. Upper glume 1 nerved, or 3 nerved. Spikelets of defferent plants, with female-fertile florets only, or with incomplete florets. The incomplete florets distal to the female-fertile florets. The distal incomplete florets merely underdeveloped. Spikelets without proximal incomplete florets.
Female-fertile florets 2–5. Lemmas scabrous or smooth; not becoming indurated; entire; apically symmetrical and not twisted, pointed; awnless, or mucronate to awned. Awns if present, 1; median (slender, erect, briefly divergent or weakly sinuous, scabrid, 0.2–3(5) mm long, from the keel vein); apical; non-geniculate; hairless; much shorter than the body of the lemma to about as long as the body of the lemma; entered by one vein. Awn bases not twisted. Lemmas hairy to hairless (glabrous or with stiff hairs to 1 mm on the keel and sometimes on the marginal veins at the base); glabrous, or scabrous; carinate; "weakly". Palea present; relatively long; awnless, without apical setae; 2-keeled. Palea keels glabrous to hairy. Lodicules present; 2; membranous; shortly toothed to not toothed. Stamens in female-fertile florets, 3 (or three 1–3 mm long staminodes in female flowers). Anthers 2–3 mm long; not penicillate; without an apically prolonged connective. Ovary apically glabrous. Styles free to their bases. Stigmas white.
Fruit, embryo and seedling. Fruit fusiform; longitudinally grooved; sub- trigonous; firm or sometimes softish, glabrous. Hilum short (1/5–1/3 the grain in length). Endosperm with lipid.
Transverse section of leaf blade, physiology. Presumably C3. Leaf blade with distinct, prominent adaxial ribs ("with blocky flat-topped or broadly rounded costal ridges"). Bulliforms present in discrete, regular adaxial groups (in all the grooves, unlike the situation supposed usual in Poa s. str., where they occur only alongside the midrib). Combined sclerenchyma girders present; forming figures.
Classification. Watson & Dallwitz (1994): not described separately. Soreng et al. (2015): Pooideae; Poodae; Poeae; Poinae. 6 species (N. andina, N. chonotica, N. erinacea, N. pugioni-folia, N. robusta, N. subnervis).
Distribution, phytogeography, ecology. Argentina, Chile, and south through Patagonia to coastal and interior Tierra del Fuego, Isla de Estados and Falkland/Malvinas Islands.
Hydrophytic to helophytic; halophytic to glycophytic. In permanent or seasonally wet ground, or shallow water, in fresh water or frequently in subsaline, saline, or mineralized soils of coastal sands and estuaries, springs, bogs, marshes, springy meadows, wet rocks, and riparian meadows, from sea level to over 3200 m.
Special comments. Anatomical data wanting (but the Soreng & Gillespie (2007) description offers nothing to suggest that the usual implicit values should not stand).
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’.