Potamogeton berchtoldii Fieber (1838: 277)

Abbasi, Shabnam, Afsharzadeh, Saeed, Dinarvand, Mehri & Wiegleb, Gerhard, 2017, Synopsis of Potamogetonaceae in Iran with supplements to the Flora Iranica and a new identification key, Phytotaxa 311 (1), pp. 1-21 : 6

Potamogeton berchtoldii Fieber (1838: 277) , Fig. 4

Annual or biennial, rhizome filiform, stem filiform, terete, with two distinct glands at leaf base. Leaves monomorphic; submersed leaves sessile, 15–45 mm long, 1.5–2 mm wide, margins entire, 3-veined with at least 2 rows of lacunar cells along the shiny yellow midrib, acuminate at apex, cuneate at base; floating leaves absent. Stipules not fused, convolute at base, 5–9 mm long, membranous. Spike 4–5 mm long, peduncle <1cm long, as thick as the stem. Tepals 2 mm long, anthers 0.5 mm long. Carpels 4, fruits 2 mm long. Stele of circular type, endodermis of O-type, interlacunar bundles absent, subepidermal bundles present.

Worldwide distribution: —W Asia ( Turkey, Iraq), circumpolar, boreal and temperate regions throughout the northern hemisphere.

Distribution in Iran: —North, West, South.

Flowering time: —From spring to autumn.

Specimen examined:— IRAN. Gilan: Astaneh, under Sefidrood bridge, 94 m, 12 July 2009 Dinarvand 8156 (Herbarium of the Research Center of Agriculture & Natural Resources of Khuzestan!) ; Mazandaran: Shoormast river , 916 m, 13 Aug 2014, Abbasi & Afsharzadeh 20214 ( HUI!) ; Kurdistan: Ravansar, 1430 m, 10 Aug 2008, Dinarvand 27447 (Herbarium of the Research Center of Agriculture & Natural Resources of Khuzestan!) ; Khuzestan: Khoramshahr, 500 m, 10 June 2010 Dinarvand 8059 (Herbarium of the Research Center of Agriculture & Natural Resources of Khuzestan!) ; Lorestan: Pole dokhtar: Lefone wetland, 730 m, 12 July 2010, Dinarvand 8713 (Herbarium of the Research Center of Agriculture & Natural Resources of Khuzestan!) ; Lorestan: Gahar lake, 2350 m, 12 July 2010, Dinarvand 8755 (Herbarium of the Research Center of Agriculture & Natural Resources of Khuzestan!) ; Yazd: Afshar vale, wetland, 2100 m, 1 July 1998, Edmonson & Miller 1494 ( TARI!) ; Fars: Tangeboragh dam, 1230 m, 2 July 2010, Dinarvand 866 (Herbarium of the Research Center of Agriculture & Natural Resources of Khuzestan!) ; Semnan: Touran conserved area, 1300 m, 6 Aug 2011, Dinarvand 13804 (Herbarium of the Research Center of Agriculture & Natural Resources of Khuzestan!) .

Figures

FIGURE 4. P. berchtoldii a. cross section of stem (Scale bar: 100 μm, objective lens 4), b. morphological shape.