DELTA home

The grass genera of the world

L. Watson, T.D. Macfarlane, and M.J. Dallwitz

Sylvipoa Soreng, L.J. Gillespie & S.W.L. Jacobs

~ Poa

Type species: S. queenslandica (C.E.Hubb.) Soreng, L.J. Gillespie & S.W.L. Jacobs.

Habit, vegetative morphology. Perennial; erect or geniculate, caespitose. The flowering culms leafy. Culms 40–150 cm high; herbaceous; branched above; not tuberous; 5–9 noded. Culm nodes exposed; glabrous. Culm internodes hollow. Young shoots extravaginal. The shoots not aromatic. Leaves mostly basal; more or less non-auriculate (the auricles vestigial). Sheath margins free (to the node). Leaf blades linear (acuminate); apically cucullate; broad; 16–40 cm long, 4–17 mm wide; flat; not pseudopetiolate; cross veined; rolled in bud. Ligule an unfringed membrane; laciate or laciniate, truncate; 2–4.5 mm long.

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

Inflorescence. Inflorescence exserted, paniculate; open; symmetrical. Rachides subterete or flattened. Inflorescence espatheate; not comprising ‘partial inflorescences’ and foliar organs. Spikelets spreading, erect, 2–3 per ultimate branch, solitary.

Female-fertile spikelets. Spikelets 3–6.5 mm long; oblong, or elliptic, or lanceolate, or ovate; somewhat compressed laterally; disarticulating above the glumes; disarticulating between the florets. Rachilla prolonged beyond the uppermost female-fertile floret; hairless; the rachilla extension with incomplete florets. Hairy callus present. Callus short.

Glumes two; more or less equal (subequal, the lower slightly shorter); shorter than the spikelets; shorter than the adjacent lemmas (half its length to slightly shorter); hairy; pointed to not pointed; muticous, awnless; carinate; narrowly ovate, elliptic or oblong membranous or chartaceous, similar. Lower glume shorter than the lowest lemma; 1 nerved, or 3 nerved. Upper glume 3 nerved. Spikelets with female-fertile florets only, or with incomplete florets. The incomplete florets when present, distal to the female-fertile florets. The distal incomplete florets when present, 1; merely underdeveloped; awnless. Spikelets without proximal incomplete florets.

Female-fertile florets 1–6. Lemmas narrowly ovate to elliptic; similar in texture to the glumes; not becoming indurated; entire; pointed; muticous, awnless; hairy (over and between the veins); carinate; without a germination flap; 5 nerved; with the nerves non-confluent. Palea present; relatively long (somewhat shorter than the lemma); tightly clasped by the lemma; entire, or apically notched; thinner than the lemma; 2-nerved; 2-keeled. Palea back scabrous (papillose, scaberulous or scabrous). Palea keels wingless; scaberulus above. Lodicules present; 2; free; membranous; glabrous; toothed, or not toothed; not or scarcely vascularized. Stamens 3. Anthers 1–1.8 mm long; not penicillate; without an apically prolonged connective. Ovary apically glabrous; obovoid, without a conspicuous apical appendage. Styles 2, free to their bases. Stigmas 2; with conspicuous secondary branching, white.

Fruit, embryo and seedling. Fruit free from both lemma and palea; small (1.4–1.6 mm long); brown; oblong or fusiform, or ellipsoid; not grooved; terete, not noticeably compressed; glabrous; smooth. Hilum short (0.15–0.2 mm long). Embryo fairly small (0.36–0.44 mm long); not waisted. Endosperm hard. Embryo with an epiblast.

Transverse section of leaf blade, physiology. Bulliforms not present in discrete, regular adaxial groups.

Classification. Watson & Dallwitz (1994): not described separately. Soreng et al. (2015): Pooideae; Poodae; Poeae; Poinae. 1 species (S. queenslandica).

Distribution, phytogeography, ecology. Australia.

Mesophytic; shade species. In and on the margins of rainforests, at altitudes usually above 1000 m.

References, etc. Morphological/taxonomic: Vickery, J.W. (1970). Contr. New South Wales Natl. Herb. 4: 180; Weiller, C.M. et al. (1995).

Special comments. Seemingly distinguished from Poa, at least in Australia, by the basal leaf sheaths not being keeled, and leaves with acuminose blade apices. Anatomical data wanting.

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.’.