Solitary graminoid herb growing in dense or loose tussocks, sometimes very large, up to more than 60 cm in diameter, with all branching inside leaf sheaths (intravaginal). Roots not curled. Basal sheath cylinders dense or loose, pale straw-coloured, with strong, pale veins. Aerial shoots with 1–2 prophylls (basal, reduced leaves without or with only a short blade). Culms 8–30(40) cm, prostrate, ascending or spreading, smooth and glabrous, with 2–3 leaves.
Leaves 5–15(20) cm long, about half as long as culms in well developed plants, flat or moderately folded, keeled and with apex like the prow of a boat, with veins on the upper surface broad and distinctly raised, on the lower surface narrow and less distinctly raised, smooth and glabrous, green, bluish green or sometimes purplish tinged. Ligula 1.5–3 mm, acute, sometimes lacerate.
The units of the inflorescence of Poaceae are the spikelets, nearly always numerous in a panicle or spike-like inflorescence. Spikelets are composed of 2 glumes (bracts for the spikelet) and one or more flowers (the term used below) or rather floral units often named ‘florets’ because we do not know what is the exact flower. A flower or floret is composed of a lemma with 1 mid vein (probably the floral bract), a palea with 2 mid veins (either 2 fused bracteoles or perhaps 2 fused perianth leaves), 3 small organs called ‘lodiculae’ and essential in the opening of the flower at anthesis (possibly transformed perianth leaves or transformed stamens), 3 stamens (mostly), and a gynoecium of 2 fused carpels with 2 feathery stigmas and one seed.
Inflorescence a more or less contracted, elongate panicle, up to 5–6 × 1–1.5 cm, usually occupying less than 1/4 of culm length. Panicle with 4–7 nodes with 4–6 branches at each of the lower nodes. Branches patent or erectopatent, 10–25(30) mm, smooth or sparsely scabrous, each with 1–4(5) spikelets along much of their length. Spikelets 4–6(7) × 1.8–2.0(2.5) mm, with 4–6(7) flowers. Bracts (glumes and lemmas) with rounded backs. Glumes unequal, fairly flimsy, both much shorter than the lower lemmas, smooth and glabrous. Lower glume 1.0–1.5 × 0.8–1.1 mm, ovate or lanceolate, usually acute, with 1(3) veins, violet, without or with a very narrow, white hyaline margin; upper glume 1.3–2.2 × 1.0–1.5 mm, ovate, acute or subacute, sometimes slightly lacerate, with 1(3) veins, violet, with a narrow, white hyaline margin at apex. Lemmas 2.5–3.5 × 0.8–1.3 mm, oblong, subacute, usually lacerate, with (5)7(9) more or less distinct veins, with long, intertwined hairs on the proximal 1/3 of the veins, otherwise smooth and glabrous, dark violet with a broad, golden yellow and white hyaline margin and tip. Paleas shorter than lemmas, with veins with intertwined hairs in their proximal part, scabrous in their distal part. Anthers 0.5–0.8 mm.
Fruit an achene (with one seed).
Sexual reproduction by seeds; no vegetative reproduction. Wind pollinated. Seed set is regular in Svalbard.
Fruits (inside florets) have no special adaptations to dispersal, probably mainly spread by wind, surface water and birds.
The species of Puccinellia can be mistaken for Poa but differ in having no keel on glumes or lemmas but rather an evenly rounded back. They also differ in lemmas broad nearly to the apex, often truncate, rounded or subacute with apex uneven, lacerate or fringed, whereas all Poa have lemmas tapering gradually towards a usually acute apex and usually entire in the margin (however, the lemmas of Poa abbreviata, P. glauca and P. hartzii may have lacerate apices).
The genus Puccinellia is notoriously difficult and with numerous species in the Arctic, many of them endemic (restricted) to the arctic regions. They are difficult also in Svalbard. We here recognize 5 species but there may be more (especially in the affinity of P. angustata).
Puccinellia phryganodes differs from all the others in being stoloniferous and asexual with aborting flowers (look for shrivelled anthers) and little flowering; all the others are tussocky, sexual and always abundantly flowering. For the unmistakeable stolons of P. phryganodes, see that species.
Puccinellia angustata and P. vahliana both have paleas with intertwined hairs on the proximal parts of the veins (keels), whereas P. coarctata and P. svalbardensis have no intertwined hairs on palea keels. Puccinellia vahliana differs most distinctly from P. angustata in the glumes. In P. vahliana they are mostly subequal, the longest about the same length as the lower lemmas, and firm; in P. angustata they are unequal, both much shorter than the lower lemmas, and flimsy.
Puccinellia svalbardensis differs from (arctic) P. coarctata most distinctly in the shape of the panicle. The panicle of P. svalbardensis is very open with very slender, spreading to patent or even retrorse, long branches; that of P. coarctata is more contracted with stouter, erect or erectopatent branches. The keels (veins) of the paleas in P. svalbardensis are smooth, those of P. corarctata scabrous at least in their distal parts. In addition, the lemmas of P. svalbardensis are lacerate, whereas those of P. coarctata are distinctly ciliolate (with one-celled teeth).Mistaking these two species is, however, impossible in practice in Svalbard as P. coarctata is a seashore species restricted to Bjørnøya, whereas P. svalbardensis mainly is an arctic steppe species and restricted to northern parts of Spitsbergen.
Puccinellia angustata is present in all zones and sections and one of the two most widely distributed species of Puccinellia in Svalbard. It occurs in a broad span of site types, all of them rich in mineral nutrients and either disturbed or manured. It is a common and often dominant species in bird cliff meadows, common in open, eroded or disturbed heaths and meadows, in screes and on land slides, on erosion banks along rivers and brooks (and coasts), and on road verges and other anthropogenic sites. The species is, however, rare or absent from the regions with only acidic substrates and is rather demanding edaphically, confined to circumneutral and basic soils.
Puccinellia angustata is recorded from all the four large islands (Spitsbergen, Nordaustlandet, Barentsøya, Edgeøya) and also from Kong Karls Land and Hopen, but not from Bjørnøya.
This species is high arctic circumpolar, not reaching, e.g., Iceland or Fennoscandia.
Puccinellia angustata is polymorphic in Svalbard but perhaps not with races that can be separated by diagnostic characters, even if two have been proposed. A prostrate plant with slender, often somewhat curved stems was described by Sørensen (1953) as var. decumbens, with type from the Adventfjorden area. We have seen this plant at several localities, and it seems to intergrade with the main form.
Another plant that was erroneously assigned to the affinity of P. angustata was reported by Elvebakk et al. (1994) from the surroundings of the warm springs Trollkjeldene at Bockfjorden (Haakon VII Land) as P. palibinii T.J.Sørensen. Puccinellia palibinii is otherwise known (and originally described) from Novaya Zemlya. Tzvelev (1971) reduced P. palibinii to a subspecies, P. angustata ssp. palibinii (T.J.Sørensen) Tzvelev. Our report of this species from Svalbard was, however, a mistake as the plants at Trollkjeldane belong to P. svalbardensis. N.N. Tzvelev studied the relevant material in 1999, and also he concluded that it did not belong to P. palibinii but to P. svalbardensis.
However, Tzvelev identified other Svalbard specimens as belonging to P. palibinii, among them two of the specimens annotated by Sørensen as P. angustata var. decumbens. If we have a taxonomic variation in Svalbard P. angustata, it may be as ssp. angustata and ssp. palibinii (=P. angustata var. decumbens).
Elvebakk, A., Elven, R., Spjelkavik, S., Thannheiser, D. & Schweitzer, H.-J. 1994. Botrychium boreale and Puccinellia angustata ssp. palibinii new to Svalbard. – Polarflokken 18: 133–140.
Sørensen, T.W. 1953. A revision of the Greenland species of Puccinellia Parl. – Meddelelser om Grønland 136(3). 179 pp.
Tzvelev, N.N. 1971. Zametki o zlakach flory SSSR, 6. – Novosti Sistematiki Vysshykh Rastenii 8: 57–83.