Poa orienti-sibirica Olonova, 2018

Olovona, Marina V. & Nikolin, E. G., 2018, Bluegrasses (Poa L., Poaceae) of Sakha (Yakutia) Republic, an annotated checklist, Adansonia (3) 40 (7), pp. 89-102 : 96

29. Poa orienti-sibirica Olonova , sp. nov. ( Fig. 2 )

A Poa stepposa (Krylov) Roshev. pilosis rachillis atque, P. skvortzovii Prob. longis ligulis praecipue differt.

TYPE. — Russia. Chitinskaya oblast, Sretenskiy district, vicinity Sretensk city, shrubby steppe slope, 06.VII.1990 , V. Kurbatskiy , M. Olonova , S. Kobylenko & E. Sytina s.n. (holo-, TK [TK-001731]) . P ARATYPES. — Russia. Chitinskaya oblast, Mogochinskiy district, vicinity settlement Sobolino , dry birch-pine forest along the slope, 08.VII.1990 , V. Kurbatskiy , M. Olonova , S. Kobylenko & E. Sytina s.n. ( TK). — Republic Buryatia, Baykalskiy ridge, cape Khibilen, stony bank of Baikal, 17.VIII.1981 , V. Kurbatskiy , M. Olonova & O. Lishen s.n. ( TK). — Republic Sakha (Yakutia), Viluysky district , road Viluysk-Voronovo , right bank of Viluy river , pine forest with Arctostaphylos uva-ursi and lichens, 63°42’48”N, 121°31’42”E, alt. 162 m, 09.VII.1996 , E. G. Nikolin s.n. ( TK). — Republic Buryatia, Baykalskiy ridge, Baikal vicinity, cape Bolsodoy, stony bank of dry brook, 14.VIII.1981 , V. Kurbatskiy , M. Olonova & O. Lishen s.n. ( TK, LE). DISTRIBUTION AND HABITAT. — East Siberia. It occurs on dry steppe slopes, among bushes, in dry pine forests, cliffs and stony banks. – Dry forests, dry rocky and gravel slopes: C-Y .

GENERAL DISTRIBUTION. — East Siberia.

AFFINITIES. — Poa orienti-sibirica probably is a stable hybridigenous species. New species is morphologically close to P. stepposa and P. skvortzovii . It differs from P. stepposa by pilose rachilla; from P. skvortzovii it differs by long ligule.

DESCRIPTION

Plants perennial, culms slightly scabrous, erect, densely tufted, 30-60 cm tall, nodes 2 or 3, uppermost to 1/3 way up culm. Extravaginal branching prevailing. Upper leaf sheeth closed for 1⁄6 of lenth, scabrid, usually longer than blade; blade narrowly linear, flat or folded, 0.5-1.2(-3) mm wide, scabrid.Apex point- ed, never naviculate. Ligules of flag leaves (1.6) 2–2.5(3) mm, slightly pointed. Panicles more or less spreading to spiciform, (4.5-)6-10(-17) × 1-3-5) cm; branches densely scabrous, erect, (1⁄5-1/4-1/3-1/2) × as long as panicle. Spikelets lanceolate, (3-) 3.5- 4.5mm, light green or yellowish, apex yellow, rarely more or less violet, florets 2-5; rachilla pilose. Glumes subequal, lanceolate, 3-4 mm, glabrous or slightly scabrous. Lemma 3.5-4 mm, keel shortly villous for 1/2 of length, marginal veins for 1/3, area between veins glabrous, callus webbed to almost glabrous; palea glabrous between keels, with short spinules along keels. Anthers 1.3-2 mm, ovary light brown. Fl. 6-8.

Figures

FIG. 2. — Poa orienti-sibirica Olonova, sp. nov.: A, holotype; B, lemma; C, ligule; D, rachilla. Scale bars: B-D, 1 mm.