Panarctic Flora

840103 Campanula rotundifolia L.

• L., Sp. Pl.: 163 (1753). Lectotype (LINN): Europe. Herb. Linn. 221.5 (Böcher 1966b: 292).

2n= (1) 32 34 (2x). - Europe (N), Russia (N), Siberia (S), Far East (N), Canada, U.S.A., Greenland. - Numerous reports, many Atlantic ones for "gieseckiana", some Siberian and Far East ones for "langsdorffiana".
(2) 51 (3x). - Europe (Norway). - Laane et al. (1983).
(3) 68 72 (4x). - Europe, Russia, Canada, U.S.A., Greenland. - Numerous reports, some from Canada and Greenland for "groenlandica".
(4) 102 (6x). - Europe (N, C, S). - Numerous reports.
Taylor and Mulligan (1968) reported two counts of 2n = 102 (6x) from British Columbia for the related C. alaskana (A. Gray) Wight ex J.P. Anderson.

Geography: Circumboreal-polar.

Notes: The infraspecific variation in Campanula rotundifolia is appreciable and has been treated in many ways (e.g., Podlech 1962, 1965; Böcher et al. 1978; Shetler 1982). Diploids and tetraploids are well documented from arctic and near arctic areas and also hexaploids from farther south (e.g. Böcher 1936, 1960; Gadella 1964; Laane 1968; Kovanda 1970; Croff 1978; Laane et al. 1983; Nurmi 1986). Four names have been applied: "gieseckiana" in the North Atlantic regions for a diploid (2n = 34) and mainly arctic plant with, e.g., one or a very few large flowers per stem; "groenlandica" in the North Atlantic regions for a morphologically similar tetraploid (2n = 68) plant; "rotundifolia" (s. str.) throughout for a tetraploid (and hexaploid) plant with, e.g., often smaller and more numerous flowers per stem; and "langsdorffiana" in eastern and northeastern Asia for a diploid but morphologically more different plant (see Olonova 1996). There are a few additional differential characters, mostly quantitative ones. They are not sufficient for unambiguous separation, except for "langsdorffiana" which we accept. The other races are entered as provisional subspecies.

Böcher et al. (1978) recognized the Greenland plants as C. gieseckiana with two races: a widely distributed subsp. gieseckiana (diploid) and a more restricted southern and eastern subsp. groenlandica (tetraploid). Shetler (1982) treated the plants in the northern parts of North America as a single variable C. rotundifolia with many 'races' or tendencies and discussed its cytogeography. In Fennoscandia, two ploidy levels and two morphological appearances combine into possibly four taxa. Only tetraploids are found in the western and southern parts, both as lowland plants with many and comparatively small flowers ("rotundifolia") and as alpine plants with often single, large flowers ("groenlandica"). There seems to be little or no discontinuity in the morphological patterns. Diploids ("gieseckiana") are dominant or perhaps exclusive in the northeastern, arctic and near arctic corner of Norway and nearby northern Finland (Croff 1978; Laane et al. 1983), with the morphological pattern of the tetraploid mountain plant. However, diploids (nameless) also occur in the eastern lowlands in Sweden and Finland with the morphological pattern of the tetraploid lowland plant. The plants of the single known Svalbard population are diploid (Flovik 1940) and correspond morphologically with the Greenland ("gieseckiana") and northeastern Fennoscandian diploids. It seems to be difficult to consistently separate diploids and tetraploids - or mountain-tundra and lowland plants - on two taxa in northern Europe and Greenland. The hexaploids do not seem to reach the Arctic but one hexaploid has been found in northern Norway (Laane et al. 1983).

Hultén and Fries (1986) treated most of the variation as some informal races: "typical C. rotundifolia" (small-flowered and comparatively southern), a "large-flowered race" (northern), and a "Rocky Mountains subspp.", but they accepted the Siberian subsp. langsdorffiana from the Jenisei east to the Pacific Ocean. Olonova (1996) drew the limit between C. rotundifolia s. str. and subsp. langsdorffiana between Taimyr and the Olenyok-Lena rivers. Kozhevnikov (1996) assigned all plants from the Russian Far East to C. langsdorffiana.

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  Source: Farbenfreude at Wikispecies