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 : 96-100

30. Poa filiculmis Roshev.

In Botanicheskiye Materialy Gerbariya Botanicheskogo Instituta im. V. L. Komarova AN SSSR 11: 29 (1949). — Tzvelev, Arctic Flora of the USSR 2: 153 (1964); Grasses of the USSR: 474 (1976). — Olonova, Flora of Siberia 2: 183 (1990). P. stepposa (Kryl.) Roshev. , Flora Turkmenii 1: 145 (1932a). — Per-

filjeva, Identification Book of High Plants of Yakutia: 75 (1974). TYPUS. — “Basin of Rv. Anadyr: valley of rv. Anadyr: mouth of Rv. Majna: on sands. 1160; 13.VII.1933. I.Vasilev” ( LE!) ( Tzvelev 1976: 474). — Pebbly and sandy river and stream banks: Arc, Kol .

KEY FOR IDENTIFICATION OF BLUEGRASSES ( POA L. ) IN YAKUTIA

1. Uppermost sheeths closed for 2/3 or more. Lemmas completely glabrous. Plants predominantly in forest belt. The leaf blades 1.5-4 mm width, the stems in the lower nodes are 1-2 mm in diameter ............. 3. P. sibirica Roshev.

— Uppermost sheaths closed less than 2/3 ......................................................................................................... 2

2. Uppermost sheaths closed for more than 1/4 ................................................................................................. 3

— Uppermost sheaths closed for less than 1/4 .................................................................................................. 21

3. Lemma callus glabrous ................................................................................................................................ 4

— Lemma callus with a tuft of long hairs, sometimes negligible ....................................................................... 5

4. Anthers not more than 1 mm long ........................................................................................... 2. P. annua L.

— Anthers more than 1 mm long ......................................................................................... 1. P. supina Schrad.

5. Anthers 0.6-0.8 mm long. Plants 5-25 cm high ........................................ 20. P. paucispicula Scribn. & Merr.

— Anthers 1 mm or longer .............................................................................................................................. 6

6. Paleas, and most often lemmas, are pubescent between keels (veins). Plants of Arctic or upper mountain belt ........... 7

— Both paleas and lemmas, are glabrous between keels (veins), lemmas pubescent along veins only. Plants of plains and lower mountain belt ........................................................................................................................... 13

7. Spikelets 4-6 mm long, arctic and subarctic plants ...................................................................................... 8

— Spikelets 6-8 mm long, arctic and arcto-alpine plants ................................................................................ 10

8. Plants with long thin creeping shoots .................................................................................. 8. P. arctica R.Br.

— Plants tufted, with a small number of shoots or without them ..................................................................... 9

9. Loosely tufted. Panicle dense, compressed, with viviparous spikelet ............................ 9. P. lindebergii Tzvelev

— Densely tufted. Panicle open, without viviparous spikelet ..................................... 17. P. tolmatchewii Roshev.

10. Plants of the upper mountain belt on the South of Yakutia ........................................ 7. P. smirnowii Roshev.

— Arctic plants of the North-East of Yakutia ................................................................................................. 11

11. Sheathes of the uppermost leaves as long as their blades .......................................... 6. P. platyantha Komarov

— Sheathes of the uppermost leaves twice longer than blades ........................................................................ 12

12. Plants with creeping shoots, not tufted. Lemma along keel and marginal veins with abundant long (more than 1 mm) hairs ........................................................................................................ 4. P. lanata Scribn. & Merr.

— Plants form turfs , sometimes rather dense, connected by short creeping shoots. The hairs along keel and marginal veins of lemma not exceeding 1 mm ...................................................................... 5. P. malacantha Komarov

13. Plants with hard grayish-green leaf blades .................................................................................................. 14

— Plants with more or less soft green or bluish waxy leaf blades ................................................................... 16

14. Leaves of innovations flat, 2–4 mm wide, slightly fleshy, folded, arcuate ........................................................ .............................................................................................. 15. P. tianschanica (Regel) Hack. ex O. Fedtsch.

— Leaves of innovations narrow, convolute, up to 1 mm in diameter, setiform .............................................. 15

15. Innovations and flowering shoots are in clusters, enclosed by dead leaves sheaths ............. 12. P. angustifolia L.

— Innovations single. Plants of beaches along the banks of the Lena river ...................................................... ....................................................................................................... 10a. P. pratensis subsp. skrjabinii Tzvelev

16. Plants of the Arctic, subarctic or upper mountain belt. Panicle branches smooth ........ 13. P. alpigena Lindm. , 17

— Plants of the middle and lower mountain belts or plains. Panicle branches scabrid .................................... 18

17. Panicle without proliferated (viviparous) spikelets ............................... 13. P. alpigena subsp. alpigena Lindm.

— Panicle with proliferated spikelets ..................... 13a. P. alpigena subsp. colpodea (Th. Fr.) Jurtzev & Petrovsky

18. Lemma abundantly covered with long hairs, tuft of hairs on the lamma callus is very long and dense. Arctic and subarctic plants, sometimes with viviparous spikelets ................................................. 14. P. sublanata Reverd.

— Lemma pubescence moderately developed. Meadow plants ....................................................................... 19

19. Blades of innovation leaves usually flat, more 1.2 mm wide. Forest or alluvial plants ................................. 20

— Blades of innovation leaves more than 1.2 mm wide. Meadow plants .................................. 10. P. pratensis L.

KEY FOR IDENTIFICATION OF BLUEGRASSES ( POA L. ) IN YAKUTIA (CONTINUATION)

20. Spikelets 2-3 mm long, alluvial plants ........................................... 16. P. sabulosa (Roshev.) Turcz. ex Roshev.

— Spikelets 3-5 mm long, forest plants ......................................................................... 11. P. sergievskajae Prob.

21. Anthers 0.4-1 mm long, mainly mountainous, arctic and subarctic plants ................................................. 22

— Anthers more than 1 mm long .................................................................................................................. 23

22. Panicle thick, compressed, 0.5-2.5 cm long, lemma usually pubescent between veins, rarely glabrous ............ ..................................................................................................................................... 19. P. abbreviata R.Br.

— Panicle open, 2-5 cm long, lemma glabrous between veins ............................. 18. P. pseudoabbreviata Roshev.

23. Culms (25) 30-100 cm, uppermost node is usually open. Plants of lower mountain belt ........................... 24

— Culms up to 25 (40) cm, uppermost node usually in the lower part of the stem and enclosed by sheath. Plants of arctic tundra and upper mountain belt;if in the plain then the panicle is compressed, from dense ovate to spiciform ................................................................................................................................................... 34

24. Mesomorphic plants; upper node in the upper half of the stem (rarely-slightly lower). Leaf blades soft, flat, (1-)2-4(-5) mm wide, longer than sheath; panicle open, with long branches reaching half of panicle lengh .......................... 25

— More or less xeromorphic plants; uppermost node in the lower half of the culm. Leaf blades from relatively soft, withering with drying, to hard, setiform, equal to sheath or slightly shorter. Panicle quite narrow, with long branches reaching 1/3 of panicle lengh ........................................................................................................ 27

25. Ligule of uppermost leaves (1.8) 2–3 mm long ............................................................................. 22. P. palustris L.

— Ligule of uppermost leaves 0.2–1.5 (2) mm long ....................................................................................... 26

26. Rachilla glabrous ................................................................................................... 23. P. intricata Wein (pro hybr.)

— Rachilla pubescent ............................................................................................................. 21. P. nemoralis L.

27. Uppermost node between the half and lower 1/3 of culm, leaf blades soft, almost equal to sheath. Panicle branches 2.5-3 times shorter than panicle lengh ................................................................................................................ 28

— Uppermost node in the lower 1/3 of culm, leaf blades quite firm, folded, 2 or more times shorter than sheath. Panicle branches 3 and more times shorter than panicle lengh ................................................................... 29

28. Lemma callus with a tuft of long hairs. Plants mostly of Southern Yakutia ............................ 24. P. urssulensis Trin.

— Lemma callus glabrous or with poor tuft of hairs. Plants of the circumpolar area ......... 34. P. tanfiljewii Roshev.

29. Rachilla pubescent .............................................................................................................................................. 30

— Rachilla glabrous ....................................................................................................................................... 31

30. Ligule shorter than 1 (1.2) mm ............................................................................................ 25. P. skvortzovii Prob.

— Ligule longer (1.5) 2 mm ................................................................... 29. P. orienti-sibirica Olonova , sp. nov.

31. Lemma pubescent between veins ........................................................................................ 30. P. filiculmis Roshev.

— Lemma glabrous between veins ................................................................................................................. 32

32. Panicle quite open, (1.5) 2–7 (11) cm wide, especially during flowering, with branches up to 1/3 its lengh .......... 33

— Panicle narrow, compressed, spicate, up to 1.5 cm wide, with short branches not exceeding 1.5 (2) cm and usu- ally not reaching 1/3 its lengh ....................................................... 27. P. botryoides (Trin. ex Griseb.) Komarov

33. Ligule 2.5–3 mm long, culm under the panicle almost smooth. Plants of Eastern Yakutia ........... 28. P. ochotensis Trin.

— Ligule up to 2 (2.5) mm long, culm under the panicle scabrous .................... 26. P. stepposa (Krylov) Roshev.

34. Plants greyish-green, often dark-colored. Panicles from elongated to almost pyramidal, the longest branches 1.5-2 cm, spikelets from poorly crowded to scattered, (3.8) 4–6 (8) mm long; upper internode often up to 1.5–2 mm in diameter. Leaf blades folded or flat. Arctic and subarctic plants .......................................................................... 35

— Panicles from dense ovate to almost spicate, with erect branches, the longest of them up to 1 (1.5) cm, spikelets 3–4 (5) mm long, crowded on branches, upper internode relatively thin, not more than 1 mm in diameter. Leaf blades firm, setiform, when dried, wire-like. Plants of the lower mountain belt or plain .................. .................................................................................................... 27. P. botryoides (Trin. ex Griseb.) Komarov

35. Lemma callus glabrous ...................................................................................................... 32. P. anadyrica Roshev.

— Lemma callus with a tuft of hairs .............................................................................................................. 36

36. Lemma glabrous between veins ................................................................................................... 31. P. glauca Vahl — Lemma pubescent between veins ................................................................................... 33. P. bryophila Trin.

GENERAL DISTRIBUTION. — Sib., Rus. Far East.

REMARK

Closely related to Aggr. P.crymophila , which includes the populations, presumably resulted from hybridization of P. glauca s.l. and P. versicolor s.l., but, according to Tzvelev (1976) and Probatova (1985), P. arctica might be the third species, which took part in the origin of P. filiculmis .