Urss 2: 172. 37. 23. 1 Hyalopoa lanatiflora

B Colpodium subgen. Hyalopoa Tzvelev in Tolm. (1964), Fl. Arct. URSS 2: 172.

B Poa lanatiflora Roshev. (1932), Izv. Glavn. Bot. Sada AN SSSR 30: 303.

S Colpodium lanatiflorum (Roshev.) Tzvelev in Tolm. (1964), Fl. Arct. URSS 2: 172.

T Siberia: Yakutia district, Verkhoyanskii post, 17.07.1902, leg. Bruskov 111 (LE) holotype.

2n= 42+3B (6x).

2nD Jurtzev & Zhukova (1972).

G SIB

Comments:

B Poa taxon Arctophila Rupr. (1845), Fl. Samojed. Cisural. 62 [or 64].

B Poa fulva Trin. (1830), Mém. Acad. Sci. St. Pétersb., sér. 6, 1: 378.

S A. fulva (Trin.) Andersson var. pendulina (Laest.) Holmb. (1926), Skand. Fl. 2: 224; A. fulva (Trin.) Andersson. subsp. similis (Rupr.) Tzvelev in Tolm. (1964), Fl. Arct. URSS 2: 169.

T Alaska: Eschscholtz Bay, leg. L.K. Chamisso (LE) holotype?

2n= (1) 42 (6x). (2) 63 (9x).

2nD (1) Löve & Löve (1975) list numerous counts, nearly all as arctic, from most major areas. (2) Zhukova & Petrovsky (1972 Russ).

G NOR RUS SIB RFE ALA CAN GRL

Comments:

(1) The impressiv infraspecific variation is probably too insufficiently known to allow for any subspecific taxa. (Elven)

(2) The intergeneric hybrid x Arctodupontia scleroclada (Rupr.) Tzvelev (1973), Nov. Sist. Vyssh. Rast. 10: 91   basionym: Poa scleroclada Rupr. (1846), Fl. Samojed. Cisural. 63   A. fulva x Dupontia fisheri s. lat., has been reported from several places. The type collection from Malaya Zemlya tundra (Ad promont. Sanctum terrae parvae Samojedorum, leg. Ruprecht, LE) seems to be such a hybrid and is distinctive. Reported occurrences in the Chukotka area (specimens in LE inspected) were based on Arctophila fulva. According to Tzvelev and Jurtzev, there are more specimens but this must be confirmed to be an independent, reproductive entity before it can be entered in the checklist. (Elven)

Comments:

(1) The Manual of Grasses of North America will recognize only one taxon in the genus Dupontia in North America (Mary Barkworth, editor, personal communication 1999). The treatment has been written by S.J. Darybshire who may have based his opinion on the following statement in Aiken et al. (1996): "Porsild (1964) recognized this taxon [D. fisheri s. str.] and also D. fisheri subsp. psilosantha (Rupr.) Hultén, which we place in synonymy with D. fisheri. While extreme morphological expressions occur, there appears to be a continuum of variation among Canadian specimens. The characters used to separate subspecies in Europe and Russia, e.g., shape of glumes, number of florets per spikelet, lemma hairiness, and anther length, do not align consistently among North American samples."

The intention is to re-examine North American specimens for characters suggested by R. Elven before Dec. 1999 [not accomplished] to determine whether it is possible to divide the taxon. Part of my experience was based on being asked to identify specimens from around Hudson Bay that had been heavily grazed by geese. I now wonder whether D. fisheri subsp. psilosantha or D. psilosantha if grazed may produce a late season inflorescence that resembles D. fisheri s. str. (Aiken)

(2) As seen from comment (1), there is currently a difference in treatments in America (tending towards continuity - one species without subspecies   fisheri), Greenland/Norway (discontinuity - two species   fisheri and psilosantha) and Löve & Löve (1975) and Russia (discontinuity - three species/subspecies   fisheri, pelligera and psilosantha). In Tzvelev's draft all three are included as more or less circumpolar (sympatric) subspecies. From my experience, the Svalbard, Greenland and eastern Canadian material should be divided into two and only two entities. In Beringian Canada and Alaska and in Siberia the situation might become somewhat more complicated. (We should check Robert Lipkin's thesis.)

Three ploidy levels are known tetra , octo  and dodecaploids, the two first-mentioned throughout much of the range. Löve & Löve (1975) assigned each of these to one of the abovementioned taxa: fisheri (12x), pelligera (8x) and psilosantha (4x). Their reasons for this sorting are unknown and there are strong indications that the sorting is erroneous, see below.

The type material of D. fisheri R. Br. (Melville Island, syntype in HbO) belongs to the entity frequent in northern Canada and is morphologically inseparable from material collected in Melville Island in 1999 and plants from Greenland, Svalbard, Novaya Zemlya and other northern Russian areas in HbO and HbS. This plant is well known as octoploid from Svalbard (Flovik 1938, 1940 and later), and the assignment by Löve & Löve (1975) of these counts to 'D. pelligera' is just nonsense. It is worth noting that the first octoploid count outside Svalbard originate from Kolguyev Island (Sokolovskaya & Strelkova 1941), fairly close to where D. pelligera is described from (Kanin Peninsula). Our scant material from arctic Russia strongly indicate that D. pelligera only is a more southern and slightly more tall-grown facet of D. fisheri, i.e. a pure synonym, and that the entity is mainly or purely octoploid.

Löve & Löve (1975) assigned the dodecaploid chromosome number to D. fisheri s. str. The origin of the counts should be checked before this number is assigned to a taxon; the counts seem to be American. (Elven)

As to rank: In the areas where I have seen them (N Alaska, NW and N Canada, NW Greenland, Svalbard), D. fisheri s. str. and D. psilosantha look and behave as two distinct species, even if it is difficult to specify and quantify the separating characters. The problems described by Aiken from more southern parts of arctic Canada, that they may become indistinguishable in the field due to grazing of the culms and panicles by geese, should not influence our taxonomy. (Elven)

(3) After discussions in Febr. 2000 we decided upon two species. (Tzvelev & Elven)

(4) Tzvelev (1976: 488) proposed that his subsp. pelligera might be a hybrid between his subsp. psilosantha and an arctic Puccinellia, and that subsp. psilosantha on the other hand might be an ancient hybrid between Arctophila fulva and a subspecies of Deschampsia cespitosa. These hybrid hypotheses should not be taken into consideration in the taxonomic evaluation without some (strong) experimental support. (Elven)

(5) There probably is more variation than what fits into two species or subspecies. The following plants should be looked into. (A) A coarse plant with spreading ('psilosantha'-like) branches in the Beringian area. Material has been seen from N and W Alaska and NW Canada and the plants seem to be north boreal to low arctic. (B) A coarse plant with tall, erect inflorescence ('fisheri'like) characteristic of the N Russian and Siberian lower river valleys, especially pronounced along Jenisei. These are also mainly boreal plants. (C) A very strange plant, often mistaken for an Arctophila, with more numerous and less stiff culm leaves, more numerous branches and spikelets in the panicle, very small spikelets and glumes distinctly shorter than the lemmas. This plant may have been named D. micrantha Holm and seems to have a clearly arctic amphi-Atlantic distribution from NE Canada over Greenland to one small area in Svalbard. (Elven)

S D. fisheri R. Br. subsp. fisheri; D. pelligera Rupr. ex Nyman (1882), Consp. 808; D. fisheri R. Br. subsp. pelligera (Rupr.) Tzvelev (1973), Nov. Sist. Vyssh. Rast. 10: 91.

T Canada: Melville Island, 1820, leg. Mr. (G.) Fisher (BM) holotype. [Type of Poa (Dupontia) pelligera Rupr. (1845), Fl. Samojed. Cisural. 64: European Russia, Ad promontorium Kanin, leg. Ruprecht (LE), holotype?].

2n= (1) 84. (2) 88 (8x). (3) 132 (12x).

2nD (1) Zhukova (1969). (2) Flovik (1938, 1940 Svalb); Sokolovskaya & Strelkova (1941 Russ); Zhukova (1969 Russ); Packer & McPherson (1974 Ala); Löve & Löve in Löve (1975c); Engelskjøn (1979 Sb, as 2n=80-85). (3) Bowden (1960a); Löve & Löve in Löve (1975c). See comment above for the dodecaploid counts.

G NOR RUS SIB RFE ALA CAN GRL

Comments: See the genus.
37.25.2  Dupontia psilosantha (Rupr.) Griseb. in Ledeb. (1852), Fl. Ross. 4: 386.

B Poa (Dupontia) psilosantha Rupr. (1845), Fl. Samojed. Cisural. 64.

S D. fisheri R. Br. subsp. psilosantha (Rupr.) Hultén (1943), Lunds Univ. Årsskr., n. f., 2 avd., 38, 1: 226.

T Europan Russia: In litt. austr. ins. Kolgujev, leg. Ruprecht (LE) holotype?

2n= (1) 42. (2) 44 (4x).

2nD (1) Sokolovskaya & Strelkova (1941, 1960, 1962 Rs); Sokolovskaya (1955 Rs); Zhukova (1966 Rs); Sokolovskaya & Probatova in Tzvelev (1976 Rs); Engelskjøn (1979 Sb). (2) Flovik (1938 Sb); Jørgensen et al. (1958 Grl); Bowden (1960a); Löve & Ritchie (1966 Can); Johnson & Packer (1968 Ala); Löve & Löve in Löve (1975c).

G NOR RUS SIB RFE ALA CAN GRL

Comments: