Novelties in the genus Polygonum (Polygonaceae) in Turkey Author Keskin, Mustafa 0000-0003-2454-1891 Marmara University, Institute of Pure and Applied Sciences, Biology Program, 34722, Goztepe, Istanbul, Turkey & trifolium @ hotmail. com; https: // orcid. org / 0000 - 0003 - 2454 - 1891 trifolium@hotmail.com Author Severoğlu, Zeki 0000-0002-3420-3557 Marmara University, Science and Education Faculty, Biology Department, Department of Plant Diseases and Microbiology, 34722, Goztepe, İstanbul, Turkey & zseveroglu @ marmara. edu. tr; https: // orcid. org / 0000 - 0002 - 3420 - 3557 zseveroglu@marmara.edu.tr text Phytotaxa 2022 2022-03-07 538 2 113 123 journal article 20287 10.11646/phytotaxa.538.2.3 92d46141-6d3f-4554-b5de-64285fa4faff 1179-3163 6333680 A diagnostic key to of the Polygonum species occurring in Turkey follow. 1. Annuals with slender root system.......................................................................................................................................................2 - Perennials with thick and woody root system ..................................................................................................................................17 2. Achenes longer than tepals; shore plants.................................................................................................................... P. mesembricum - Achenes at most slightly longer than tepals; usually land plants .......................................................................................................3 3. Tepals 3–4 mm long; leaves 12–45 mm long, quickly deciduous...................................................................................... P. bellardii - Tepals usually shorter than 2.5 mm long; leaves average 5–25 mm long not quickly deciduous......................................................4 4. Ochrea without veins..........................................................................................................................................................................5 - Ochrea veined.....................................................................................................................................................................................6 5. Leaves revolute, obovate; plants usually erect......................................................................................................... P. cappodocicum - Leaves flat, linear to lanceolate; plants prostrate ..................................................................................................... P. polycnemoides 6. Tepal pouched at base....................................................................................................................................................... P. buxiforme - Tepal smooth, not pouched.................................................................................................................................................................7 7. Inflorescence short and congested, spike like; mostly growing in dunes or fine-grained soil........................................ P. arenarium - Inflorescence long and loosely arranged; mostly growing in land.....................................................................................................8 8. Most of middle leaves up to 2 mm wide ............................................................................................................................................9 - Most middle leaves wider than 2 mm ...............................................................................................................................................14 9. Internodes very short and covered by leaf and ochrea; achenes usually black ......................................................... P. rottboellioides - Internodes not covered by leaf and ochrea; achenes brown to dark brown......................................................................................10 10. Flowers solitary in axils of scarious bracts; leaves subulate to filiform, 0.5 mm wide................................................ P. salsugineum - Flowers 1–3 in axils of leaflike bracts; leaves 0.8–2.2 mm wide.....................................................................................................11 11. Short and sterile shoots present; the edges of the leaves here are folded longitudinally; fruiting tepals suburceolate to urceolate.... ............................................................................................................................................................................................ P. urnigera - Sterile shoots absent; leaves flat or rarely somewhat folded; fruiting tepals at most suburceolate (some perennials e.g. P. karacae ) but usually adjacent at the tip or open..............................................................................................................................................12 12. Longest pedicel 2.0– 2.5 mm , longer than tepals ............................................................................................................ P. pulchellum - Longest pedicel usually shorter than 2 mm , shorter than tepals.......................................................................................................13 13. Tepal tube about as long as the lobes; ochrea 3–8 mm long ......................................................................................... P. arenastrum - Tepal tube much shorter than the lobes; ochrea 6–12 mm long ...................................................................................... P. rurivagum 14. Inflorescence usually 4–6 flowered; veins usually not branched on tepals at fruiting time.............................................................15 - Inflorescence usually 1–3 flowered; veins branched on tepals at fruiting time ...............................................................................16 15. Leaves fresh green; ochrea 8–10 mm ; pedicels 1.5–3.0 mm; achenes tuberculate........................................................... P. aviculare - Leaves bluish-green; ochrea 4–8 mm ; pedicels 1–2 mm ; achenes smooth................................................................ P. argyrocoleon 16. Leaves 25–40 mm ; ochrea 7–9 mm ; achenes 2–2.5 mm ..................................................................................................... P. patulum - Leaves 4–35 mm ; ochrea 4–8 mm ; achenes 1.2–1.8 mm ................................................................................................ P. neglectum 17. Shore plants; ochrea longer than nodes .......................................................................................................................... P. maritimum - Land plants; ochrea usually shorter than nodes.................................................................……….……………….……….……... 18 18. Ochrea 3–nerved, entirely membranous and equal or longer than internodes ................................................................. P. cognatum - Ochrea (5–)10–nerved, tube brownish, shorter than internodes.......................................................................................................19 19. Leaf-like bracts absent towards the top............................................................................................................................... P. karacae - Bracts similar to leaves but shorter ..................................................................................................................................................20 20. Ochrea and leaves overlapping; the plant looks whitish due to hyaline ochrea; leaves mucronate; tepals 1–1.5 mm long ................ ................................................................................................................................................................................. P. paronychioides - Not as above .....................................................................................................................................................................................21 21. Leaves quickly deciduous at flowering time; plant prostrate with some shoots erect ............................................... P. e quisetiforme - Leaves not deciduous at flowering time; plants usually strict..........................................................................................................22 22. Prostrate or stoloniferous plants with 40–150 cm tall; inflorescence present on short and third shoots ........................... P. longipes - Plants suffrutescent with hard woody stocks; inflorescence usually on main shoots ......................................................................23 23. Tepals shorter than 2.5 mm long ......................................................................................................................................................24 - Tepals longer than 2.5 mm long .......................................................................................................................................................27 24. Stem and leaves ashy–glaucous; tepal with sparse pink glands near the base ............................................................. P. praelongum - Stem and leaves green; tepal unglandular ........................................................................................................................................25 25. Inflorescence a lax, elongated spike; leaves overlapping at the base; tepals 1.7–2.0 mm long.................................... P. s alebrosum - Inflorescences densed, like a head or congested spike; leaves loosely not overlapping; tepal 2.0– 2.5 mm long............................26 26. Stem 15–70 cm ; 2–4 flowers in fascicle; pedicels 1–3 mm ................................................................................................ P. melihae - Stem 21–32 cm ; 5–7 flowers in fascicle; pedicels 3–5 mm ............................................................................................ P. afyonicum 27. Leaves pustulate; achenes longer than tepals .............................................................................................................. P. istanbulicum - Leaves smooth; achenes shorter or at most equal to tepals ..............................................................................................................28 28. Flowers sessile or rarely with at most 1.5 mm pedicel..................................................................................................... P. sivasicum - Flowers obviously pedicellate ..........................................................................................................................................................29 29. Leaves usually 10 mm wide and strongly revolute at the margin .................................................................................... P. luzuloides - Leaves 4–5 mm wide on average and flat or slightly revolute margin.............................................................................................30 30. Ochrea not veined; tepals 3.5–4.5 mm long; achenes equal to slightly longer than tepals ............................................ P. ekimianum - Ochrea strongly veined; tepals 2.5–3.5 mm long; achenes slightly shorter than tepals...................................................................31 31. Leaves usually undulate margin; achenes brown ......................................................................................................... P. samsunicum - Leaves flat margin; achenes blackish .................................................................................................................................. P. setosum