21Potamogetonaceae (Draft: N.N. Tzvelev)
SRuppiaceae (incl.)
Comments:
(1)Opinions about the inclusion of Ruppia in Potamogetonaceae? Many European authors tend to do so whereas, e.g., Haynes (2000, Fl. N. Amer. 22) keeps it as a separate family. (Elven)
21.1Potamogeton L. (1753), Sp. Pl. 126.
Comments:
(1)Tzvelev keeps Potamogeton in a collective sense in his draft with two subgenera, Potamogeton and Coleogeton. Haynes & Hellquist (2000, Fl. N. Amer. 22) recognise the 'Coleogeton' group as a separate genus - Stuckenia. There are arguments for both solutions but if we generally are to recognise distinct 'segregates' as genera, Stuckenia is an obvious case. I therefore propose that we accept the current North American treatment. (Elven)
(2)There is an abundance of reported hybrids and nearly all of them may occur, at least locally, more or less independent of their parents. They also reproduce, albeit by vegetative means, and may form very large 'stands' or clones, often in long stretches of rivers. To be accepted for entry, a hybrid of Potamogeton (and other potentially clonal aquatic plants) must occur in a region from which at least one of its parents is lacking. No hybrids are therefore accepted for the list in Potamogeton s. str. (Elven)
Sect. Potamogeton
21.1.1Potamogeton natans L. (1753), Sp. Pl. 126.
S
2n=(1) 42. (2) 52 (4x).
2nD(1) Stern (1961 Bull. Torrey Bot. Club 88: 411-414). (2) Löve & Löve (1975) list several counts, one Icelandic. See also Bolkhovskikh et al. (1969).
GICE RUS SIB CAN? GRL
Comments:
(1)The 2n=42 chromosome count needs verification before acceptance. (Elven)
(2)Also approaches the Arctic in N Norway and Canada (Hudson Bay area). (Elven)
21.1.2Potamogeton epihydrus Raf. (1808), Med. Repos. 2, 5: 354.
S
2n=26 (2x).
2nDHaynes & Hellquist (2000, Fl. N. Amer. 22, secondary report).
GCAN?
Comments:
(1)Mapped by Haynes & Hellquist (2000) very close to 'our' Arctic east of James Bay. This might be the Knob Lake occurrence (5448'N) listed by Scoggan (1978) and then probably south of the border. A border case? Tentatively added. (Elven)
WARNING! Will probably be excluded as non-arctic.
21.1.3Potamogeton gramineus L. (1753), Sp. Pl. 127.
S
2n=52 (4x).
2nDLöve & Löve (1975) list several counts, one Icelandic; see also Bolkhovskikh et al. (1969).
GICE NOR RUS SIB ALA CAN GRL
Comments:
(1)The hybrids P. gramineus x lucens (P. x zizii Mert. & Koch (1823), ***) and P. gramineus x perfoliatus (P. x nitens Web. (1787), ***) might be two other candidates for inclusion, from a European viewpoint. (Elven)
21.1.4Potamogeton alpinus Balb. (1840), Mém. Acad. Sci. Turin 10-11 (Phys. & Math.) 1: 329.
S
Comments:
(1)The differences given by e.g. Fl. Arct. URSS between the two entities are mainly quantitative and justify treatment as two nearly vicariant subspecies rather than species. I therefore fully support Tzvelev's proposal here. (Elven)
(2)Haynes & Hellquist (2000) give the original publication as: Balb. (1804), Misc. Bot. 13. (Elven)
21.1.4.1Potamogeton alpinus Balb. subsp. alpinus
S
2n=52 (4x).
2nDLöve & Löve (1975) list several counts, one Icelandic.
GICE NOR RUS SIB
Comments:
21.1.4.2Potamogeton alpinus Balb. subsp. tenuifolius (Raf.) Hultén (1937), Fl. Aleut. Isl. 65.
BP. tenuifolius Raf. (1811), Med. Repos. New York, ser. 3, 2: 409.
S
2n=52 (4x).
2nDLöve & Löve (1975) list two non-arctic counts.
GSIB RFE ALA CAN GRL
Comments:
(1)Böcher et al. (1978) report only subsp. tenuifolius from Greenland. (Elven)
21.1.5Potamogeton perfoliatus L. (1753), Sp. Pl. 126.
S
Comments:
(1)Potamogeton richardsonii differs from P. perfoliatus in comparatively few diagnostic characters and is distributed like a major geographical race (i.e. subspecies). I find this case quite parallel to P. alpinus and have changed to subspecies from Tzvelev's treatment as species. (Elven)
21.1.5.1Potamogeton perfoliatus L. subsp. perfoliatus
S
2n=(1) 26 (2x). (2) c. 48. (3) 52 (4x). (4) 78 (6x).
2nD(1-3) See Bolkhovskikh et al. (1969). (3) Löve & Löve (1975) list several counts, some as arctic. (4) Hämet-Ahti (1984 Finl).
GICE NOR? RUS SIB GRL
Comments:
(1)The diploid count (2n=26) needs verification. The 2n= c. 48 count might be aneuploid or an inexact count. The hexaploid count (2n=78) is reliable so there are two ploidy levls. (Elven)
21.1.5.2Potamogeton perfoliatus L. subsp. richardsonii (A. Benn.) Hultén (1941), Lunds Univ. Årsskr., n.f., avd. 2, 37, 1: 102.
BP. perfoliatus L. var. richardsonii A. Benn. (1889), J. Bot. 27: 25.
SP. richardsonii (A. Benn.) Rydb. (1905), Bull. Torrey Bot. Club 32: 599; P. sachalinensis Leveille (1912), Feddes Repert. 10: 441.
2n=(1) 26 (2x). (2) 52 (4x).
2nD(1) Löve (1954b); Stern (1961). (2) Löve & Löve (1975) list two non-arctic counts (and thereby exclude the previous diploid counts).
GRFE ALA CAN
Comments:
(1)Is the name P. sachalinense in current use in our sources? (Elven)
21.1.6Potamogeton praelongus Wulfen (1805), Arch. Bot. (Leipzig) 3: 331.
S
2n=52 (4x).
2nDLöve & Löve (1975) list several counts, one Icelandic. See also Bolkhovskikh et al. (1969).
GRUS SIB RFE ALA CAN GRL
Comments:
21.1.7Potamogeton lucens L. (1753), Sp. Pl. 126.
S
2n=52 (4x).
2nDPalmgren (1939 Sweden).
GRUS SIB
Comments:
(1)Border occurrences in NE European Russia and NW Siberia. (Elven)
Sect. *** ?
21.1.8Potamogeton robbinsii Oakes (1841), Mag. Hort. Bot. 7: 180.
S
2n=52 (4x).
2nDHaynes & Hellquist (2000, Fl. N. Amer. 22, secondary report).
GCAN
Comments:
(1)Mapped by Haynes & Hellquist (2000) from Nunavut, probably the Thelon R. area west of Hudson Bay. Canadians must decide whether the occurrence is inside the Arctic or not but it seems to be well inside according to our map. I have therefore added it to Tzvelev's draft.
The species (and species group) is so distinct that it probably belongs to its own section. Which? (Elven)
Sect. Graminifolii Fr. ***
21.1.9Potamogeton compressus L. (1753), Sp. Pl. 127.
SP. zosterifolius Schum. (1801), Enum. Pl. Saell. 1: 50.
Comments:
(1)The American plants differ from the Eurasian ones in several fruit features (shape, wing-like dorsal keel, and marginal and nearly erect beak) and are variously treated as a species or a subspecies. I have tentatively included them as two subspecies. The alternative is as species as (indirectly) done by Haynes & Hellquist (2000). (Elven)
21.1.9.1Potamogeton compressus L. subsp. compressus.
SP. zosterifolius Schum. subsp. zosterifolius.
2n=26 (2x).
2nDPalmgren (1939 Sweden).
GRUS
Comments:
(1)Border occurrence(s) in NE European Russia. (Elven)
21.1.9.2Potamogeton compressus L. subsp. zosteriformis (Fern.) ***
BP. zosteriformis Fern. (1932), Mem. Amer. Acad. Arts, n. s., 17: 36.
SP. zosterifolius Schum. subsp. zosteriformis (Fern.) Hultén ***
2n=52 (4x).
2nDHaynes & Hellquist (2000, Fl. N. Amer. 22, secondary reference).
GCAN
Comments:
(1)Added to Tzvelev's draft. Border occurrences in the Mackenzie River delta and possibly at Hudson Bay (York Factory). (Elven)
21.1.10Potamogeton foliosus Raf. (1808), Med. Repos. 2, 5: 354.
S
2n=28 (2x?).
2nDHaynes & Hellquist (2000, Fl. N. Amer. 22, secondary reference).
GCAN?
Comments: Subsp. foliosus in the Arctic.
(1)Tentatively added to Tzvelev's draft. Mapped by Haynes & Hellquist (2000) from east of Hudson Bay, possibly a border case. Scoggan (1978) only reported it north to Lake Mistassini, far south of the 'dot' in the referred map. (Elven)
WARNING! Canadian arctic occurrence should be confirmed before the species is accepted for the list.
21.1.11Potamogeton sibiricus A. Benn. (1890), J. Bot. 28: 300.
S
Comments:
21.1.11.1Potamogeton sibiricus A. Benn. subsp. subsibiricus (Hagström) Tzvelev (2000), Nov. Sist. Vyssh. Rast. 32: 182.
BP. subsibiricus Hagström (1916), Kongl. Sv. Vet.-Akad. Handl., n. s., 55, 5: 84.
SP. porsildorum Fern. (1932), Mem. Amer. Acad. Arts Sci. 17, 1: 40.
2n=
2nD
GRUS SIB RFE ALA CAN
Comments:
(1)Treated as a full species by Haynes & Hellquist (2000, Fl. N. Amer. 22). (Elven)
21.1.12Potamogeton obtusifolius Mert. & Koch in Röhl. (1823), Deutschl. Fl. 1, ed. 3, 855.
S
2n=26 (2x).
2nDPalmgren (1939 Sweden).
GCAN?
Comments:
(1)Included in Tzvelev's draft. No arctic Canadian occurrence is mapped by Porsild & Cody (1980) or Haynes & Hellquist (2000). (Elven)
WARNING! Will be excluded if not confirmed from arctic Canada.
21.1.13Potamogeton friesii Rupr. (1845), Beitr. Pflanzenk. Russ. Reiches 4: 43.
S
2n=26 (2x).
2nDPalmgren (1939 Sweden).
GRUS SIB CAN
Comments:
21.1.14Potamogeton strictifolius A. Benn. (1902), J. Bot. 40: 148.
SP. strictifolius A. Benn. var. rutiloides Fern. ***
2n=(1) 26 (2x). (2) 52 (4x), see comment.
2nD(1) Haynes & Hellquist (2000, Fl. N. Amer. 22, secondary report). (2) Löve (1954b).
GCAN?
Comments:
(1)The tetraploid number is excluded by Haynes & Hellquist (2000) and should be critically checked before acceptance. (Elven)
(2)Mapped well into the Arctic in NW Canada and also by Hudson Bay by Porsild & Cody (1980). All these northern occurrences are excluded by Haynes & Hellquist (2000). The specimens from arctic Canada should be checked again before the species is accepted for the list. (Elven)
WARNING! Will be excluded if not confirmed from arctic Canada.
The Potamogeton pusillus aggregate (P. berchtoldii, P. groenlandicus, P. pusillus)
Comments:
(1)Potamogeton pusillus s. str. has been very much confused with the more northern P. berchtoldii. Some sterile hybrids between these two are reported but no fertile intermediates. They seem to be very clear species. Haynes & Hellquist (2000) treated them as two (largely sympatric) subspecies but give no arguments for this. Status as two species is proposed for the checklist.
The validity of P. groenlandicus as a species should be evaluated. However, Haynes & Hellquist (2000) give several differential characters, in addition to the assumed important difference in number of main veins in the blades. The occurrence of an endemic Potamogeton in currently and previously heavily glaciated Greenland is, however, strange. (Elven)
21.1.15Potamogeton pusillus L. (1753), Sp. Pl. 127.
SP. pusillus L. subsp. pusillus; P. panormitanus Biv. ex Guss. (1843), Fl. Sic. Syn. 1: 207.
2n=(1) 26 (2x). (2) 28.
2nD(1) Palmgren (1939). (2) Harada (1942a, 1942b, 1956); see Bolkhovskikh et al. (1969).
GCAN?
Comments:
(1)Not fully accepted yet. Scoggan's (1978) report of P. pusillus s. str. north to Hudson Bay (York Factory, 'West Hudsonian') indicates some Canadian confusion between P. berchtoldii and P. pusillus. Haynes & Hellquist (2000) exclude the Hudson Bay occurrences but map occurrences along Mackenzie R. to the sea. Canadians, please check whether there are clear specimens of P. pusillus s. str. from this area. (Elven)
(2)The 2n=28 count(s) might be aneuploid or miscount(s). (Elven)
WARNING! Will be excluded if arctoc occurrence (in Canada) not confirmed.
21.1.16Potamogeton berchtoldii Fieb. in Bercht. & Opiz (1838), Ökon.-Techn. Fl. Böhm. 2,1: 277.
SP. pusillus L. subsp. tenuissimus (Mert. & W.D.J. Koch) R.R. Haynes & Hellquist (1996), Novon 6: 370 [basionym: P. pusillus L. var. tenuissimus Mert. & W.D.J. Koch in Röhl. (1823), Deutschl. Fl., ed. 3, 1: 857]; P. pusillus auct., non L. (1753).
2n=26 (2x).
2nDLöve & Löve (1975) list several counts, one Icelandic.
GICE NOR? RUS SIB RFE CAN
Comments:
21.1.17Potamogeton groenlandicus Hagström (1916), Svenska Vetensk.-Akad. Handl., n. s., 55, 5: 127.
SP. pusillus L. subsp. groenlandicus (Hagström) Böcher ***
2n=26 (2x).
2nDJørgensen et al. (1958 Grl).
GGRL
Comments:
21.2Stuckenia Börner (1912), Abh. Naturwiss. Ver. Bremen 21: 258.
SColeogeton (Rchb.) Les & R.R. Haynes (1996), Novon 6: ***; Potamogeton Subg. Coleogeton Rchb. ***
Comments:
(1)Tzvelev includes for arctic Canada in his draft also Potamogeton latior Holub (1983), Folia Geobot. Phytotax. 18: 204, synonym: P. latifolius (J.W. Robbins ex King) Morong (1893), non Sloboda (1852). Haynes & Hellquist (2000) synonymise P. latifolius in this meaning with Stuckenia striata (Ruíz & Pavon) Holub (1997), Preslia 68: 364 [basionym: Potamogeton striatus Ruíz & Pavon (1798), Fl. Peruv. 1: 70, fig. 1066]. They map it, however, as much more southern, southwards from Oregon and Idaho. Therefore excluded. (Elven)
21.2.1Stuckenia filiformis (Pers.) Börner (1912), Fl. Deut. Volk 713.
BP. filiformis Pers. (1805), Syn. Pl. 1: 152.
S
Comments:
(1)Haynes & Hellquist (2000, Fl. N. Amer. 22) divide the species on three subspecies in North America, two of these comparable to subspecies also recognised in Eurasia. They are proposed accepted for the checklist but parallelisation with the Eurasian variation may be problematic. (Elven)
21.2.1.1Stuckenia filiformis (Pers.) Börner subsp. filiformis
SPotamogeton filiformis Pers. subsp. filiformis; Potamogeton filiformis Pers. var. filiformis.
2n=78 (6x).
2nDLöve & Löve (1975) list one Swedish and one Icelandic count.
GICE? NOR? RUS? SIB? CAN GRL
Comments:
(1)Only given as Eurasian in Tzvelev's draft. Mapped by Haynes & Hellquist (2000) also from non-arctic Alaska and Yukon and arctic NW Canada (Mackenzie R. to Coronation Gulf) and W Greenland. (Elven)
21.2.1.2Stuckenia filiformis (Pers.) Börner subsp. alpina (Blytt) R.R. Haynes, Les & M. Král (1998), Novon 8: 241.
BPotamogeton marinus L. f. alpinus Blytt in Blytt & A. Blytt (1861), Norges Fl. 1: 370.
SPotamogeton filiformis Pers. subsp. borealis (Raf.) Hultén *** [basionym: Potamogeton borealis Raf. (1808), Med. Repos. New York 5: 354]; Potamogeton filiformis Pers. var. borealis (Raf.) St. John ***.
2n=78 (6x).
2nDJørgensen et al. (1958 Grl); Löve & Ritchie (1966 N Can).
GICE? NOR? RUS? SIB? RFE ALA CAN GRL
Comments:
(1)The differences reported between subsp. alpina and subsp. filiformis seem small and perhaps not very significant. The short, dense spikes reported for subsp. alpina are also typical of the northern populations of subsp. filiformis in N Europe. The shape of the leaf apex also varies widely. Haynes & Hellquist (2000) only give subsp. alpina for North America and Asia but this is obviously erroneous as they base their subspecific name on a European (Norwegian) basionym. Blytt (loc. cit.) referred material from six sites in S Norway and typification should be based on one of these (specimens in O). It is therefore probable that this entity, if it is distinct, is circumpolar. (Elven)
(2)Potamogeton interior Rydb. (1906), Fl. Colorado 13, 14 [see Index Kewensis!] is indicated by Tzvelev as a synonym of S. vaginata (P. vaginatus) but is placed by Haynes & Hellquist (2000) in the synonymy of S. filiformis subsp. alpina. The question is perhaps irrelevant as P. interior probably is not used in our current sources. (Elven)
21.2.1.3Stuckenia filiformis (Pers.) Börner subsp. occidentalis (J.W. Robbins) R.R. Haynes, Les & M. Král (1998), Novon 8: 241.
BPotamogeton marinus L. var. occidentalis J.W. Robbins in S. Wats. (1871), Botany 40th Parallel 339.
S
2n=
2nD
GALA CAN
Comments:
(1)Given by Haynes & Hellquist (2000) as a purely N American race with arctic occurrences in W and N Alaska and several places in Canada from Mackenzie R. to Ungava. (Elven)
21.2.2Stuckenia pectinata (L.) Börner (1912), Fl. Deut. Volk 713.
BPotamogeton pectinatus L. (1753), Sp. Pl. 127.
S
2n=78 (6x).
2nDLöve & Löve (1975) list several non-arctic counts; Hämet-Ahti et al. (1984 Finl).
GRUS SIB RFE ALA? CAN?
Comments:
(1)Haynes & Hellquist (2000) exclude the actic occurrences in Canada mapped by Porsild & Cody (1980) and also the northern Alaskan occurrences. Are there documented arctic occurrences in North America? (Elven)
21.2.3Stuckenia x bottnica (Hagström) Holub ***
BPotamogeton x bottnicus Hagström (1916), Svenska Vetensk.-Akad. Handl., n. s., 55, 5: 52.
SStuckenia pectinata (L.) Börner x S. vaginata (Turcz.) Holub; Potamogeton pectinatus L. x P. vaginatus Turcz.
2n=
2nD
GRUS
Comments:
(1)Included because it occurs well outside the range of at least one of its parents (S. vaginata) and spreads independently, probably mainly by vegetative means. (Elven)
21.1.4Stuckenia vaginata (Turcz.) Holub (1984), Folia Geobot. Phytotax. 19: 215.
BPotamogeton vaginatus Turcz. (1854), Bull. Soc. Imp. Naturalistes Moscou 27, 2: 66.
S
2n=78 (6x).
2nDLöve & Löve (1975) list three non-arctic counts.
GSIB ALA CAN
Comments:
(2)Also mapped for Russian Far East (Chukotka Peninsula) by Hultén & Fries (1986). Russian opinions? (Elven)
21.1.5Stuckenia subretusa (Hagström) ***
BPotamogeton subretusus Hagström (1916), Svenska Vetensk.-Akad. Handl., n. s., 55, 5: 30.
S
2n=
2nD
GRUS SIB RFE ALA
Comments:
(1)Value of this taxon to be checked. Not included for N America by Haynes & Hellquist (2000). Has it been recombined in Stuckenia? (Elven)
21.3Ruppia L. (1753), Sp. Pl. 127.
21.3.1Ruppia maritima L. (1753), Sp. Pl. 127.
S
2n=(1) 16. (2) 20 (2x). (3) 40 (4x).
2nD(1) Haynes & Hellquist (2000 Fl. N. Amer. 22, secondary reference). (2) Markgraf (1981). (3) Löve & Löve (1975 Icel, see comment).
GRFE
Comments:
(1)The tetraploid Icelandic count listed by Löve & Löve (1975) should refer to this species as it is the only one now recognized from Iceland (but outside the Arctic) but tetraploids are unknown elsewhere in this species. It should probably be discounted as 'an optimistic tetraploid'. (Elven)
21.3.2Ruppia cirrhosa (Petagna) Grande (1918), Bull. Orto Bot. Regia Univ. Napoli 5: 58.
BBuccaferrea cirrhosa Petagna (1787), Inst. Bot. 2: 1826.
SR. spiralis L. ex Dumort. (1827), Fl. Belg. 164.
2n=40 (4x).
2nDLöve & Löve (1961b C Eur); Markgraf (1981).
GALA
Comments:
(1)Tzvelev's draft also includes R. spiralis from Iceland, or rather R. cirrhosa. All Icelandic material is now considered as R. maritima, and Ruppia does not reach the Arctic in Iceland. Haynes & Hellquist (2000), however, map it from Seward Peninsula. Therefore included. (Elven)