Poa calliopsis Litv., Fl. USSR

Poa calliopsis Litv., Fl. USSR View in CoL 2: 414, 755. 1934, isonym, nom. illeg. Figs. 1 View Fig & 2 View Fig

Dwarf rhizomatous perennials. Rhizomes long, slender, creeping. Young shoots extravaginal. Culms erect, unbranched, 1.4–15 cm tall, 0.05–0.1 cm across, terete, covered with fibrous remains of old leaf sheaths at base, glabrous; node 1, glabrous. Leaves mostly basal; leaf sheaths 1–8 × 0.1–0.2 cm, margin smooth, glabrous, surface smooth, glabrous, ribs inconspicuous; ligule membranous, 0.5–3 mm, apex truncate to obtuse, smooth, glabrous; collars glabrous, light brownish; leaf blades 0.3–4.5 × 0.1–0.3 cm, usually conduplicate, sometimes flat, margin smooth, apex prow-tipped, glabrous, surface smooth, glabrous. Spikelets arranged in panicle; panicle open, ovoid, oblong or pyramidal in outline, 1–5 × 1–3 cm, internodes 0.3–1.3 cm long; branches 1–2 per node, 0.4–2.5 cm long, capillary, spreading to reflexed, flexuous, smooth or scaberulous distally (especially the upper branches), with 2–12 spikelets clustered towards tips; pedicels smooth or scaberulous. Spikelets broadly to narrowly elliptic or ovate, 3–4.5 × 0.7–2 mm, variegated with green, purple and gold. Florets 2, bisexual; rachilla internodes 0.2–0.6 mm, smooth, glabrous; callus woolly. Lower glume elliptic, ovate or sub-flabellate, 2–3.4 × 1–1.5 mm, margin smooth, hyaline, apex acute, papery with membranous hyaline apex, smooth, glabrous, 1-veined, 1-keeled, flushed purple with green around the midvein near base; keel smooth, glabrous. Upper glume elliptic, ovate, orbicular or sub-flabellate, 2.3–3.8 × 1.3–1.8 mm, margin smooth, glabrous, apex acute to obtuse, papery with membranous hyaline apex, smooth, glabrous, 3-veined, 1-keeled, flushed purple with green around the veins; keel scabrid near apex, otherwise smooth, glabrous. Floret 1: Lemma broadly oblong to oblong-lanceolate or ovate, 2.8–4.2 × 1.5–1.6 mm, margin smooth, hyaline, glabrous, apex subacute obtuse to rounded, 5-veined, 1-keeled, outer lateral veins long-ciliate for ¼–½ of their length, intermediate veins faint to prominent, glabrous, surface between veins smooth, glabrous, flushed gold with sub-apical purple band and apical hyaline part; keel smooth, long-ciliate for ½ of its length. Palea oblong-elliptic to lanceolate-oblong, 2.3–3.8 × 0.5–0.6 mm, margin smooth, apex bluntly acute or notched to 2-toothed, membranous, glabrous or pilulose between keels proximally, 2-veined, 2-keeled, hyaline to golden; keel smooth or with few blunt teeth distally, glabrous or rarely with few cilia near base. Lodicules 2, ovate, c. 0.7 × 0.4 mm, entire or emarginated (-lobed), apex acute, often few denticulate, membranous, glabrous, hyaline. Stamens 3; filaments 0.3–0.6 mm long; anthers 0.9–2.5 × 0.2–0.3 mm, yellow. Ovary obovoid, 0.5–0.8 × 0.2–0.3 mm, apex notched, smooth, glabrous, wine red at maturity; styles 2, free, up to 0.3 mm long; stigmas 2, 0.8–1.5 × 0.6– 1.2 mm, white. Florets 2: similar to floret 1 but with shorter lemma (2.5–3 × c. 1 mm), palea (2–2.5 × 0.3–0.5 mm) and lodicules ( c. 0.6 × 0.2 mm).

Flowering & fruiting: May to August.

Habitat: Grows in alpine meadows, along streams and water bodies, on grassy slopes, in damp areas, and on dry hillocks mostly in association with Carex deasyi (C.B.Clarke) O.Yano & S.R.Zhang ( Cyperaceae ), Dracocephalum heterophyllum Benth. ( Lamiaceae ), Primula sp. ( Primulaceae ), Scrophularia wattii (Hook.f.) P.Li ( Scrophulariaceae ).

Distribution: India [ Himachal Pradesh, Jammu & Kashmir, Sikkim (present report)], Kyrgyzstan, Tajikistan, Pakistan, China, Nepal, Bhutan.

Specimen examined: INDIA, North Sikkim, towards Kerang , 5059.68 m, 13.06.2022, Maity, Mandal, Ghosh, Midday, Saha & Halder 24853, 24884 ( CUH) .

Notes: Poa calliopsis can be distinguished by the broadly blunt lemmas variegated with gold and purple. Besides, its rhizomatous habit, presence of callus hairs at the base of the florets, long cilia on the basal half of the keel (mid-vein) and lateral veins of the lemma, 2–3 teeth on the upper part of the palea keels (middle and lower parts smooth), and 0.9–2.5 mm long anthers make this species unique among all other members of the genus. Notably, in the present study few spikelets were found to have a palea with few cilia on the lower part of its keels, which is similar to P. nepalensis (Wall. ex Griseb.) Duthie. This observation corroborates Noltie (2000). However, P. nepalensis can be easily distinguished from P. calliopsis by the presence of scabrid leaf blades and 3–6 florets in a spikelet.

The new record of P. calliopsis in Sikkim Himalaya brings the number of species recognized in the genus to 33 in the state Sikkim.