Panarctic Flora


342209-11 The Festuca vivipara aggregate F. frederikseniae, F. vivipara, F. viviparoidea

Geography: Amphi-Atlantic - European (N) - Asian (NW) & amphi-Beringian.

Notes: Elven, Aiken, and Tzvelev: The viviparous plants related to the Festuca brachyphylla group, to F. ovina, and perhaps to the F. saximontana and F. lenensis groups have been treated either as races of a F. vivipara s. lat. (Frederiksen 1981) or as several species (Alexeev in several papers). They have been much disputed, also among the PAF collaborators. We agree, however, that they are separable and non-overlapping morphologically, that they probably are viviparous derivatives among sexual species or more probably their hybrids, and that they have attained morphological consistency and independent geographical ranges that justify their acceptance. Aiken and Elven initially preferred to follow Frederiksen and to consider them subspecies. Tzvelev preferred to follow Alexeev (1981, 1982, 1983, 1985) and Pavlick (1984) and to accept them as species because they are assumed to have evolved from different combinations of basic sexuals. Soreng et al. (2003) and Darbyshire and Pavlick (2007) followed the latter course. We all now accept them as species but with some modifications from Tzvelev's proposal (and Alexeev's accounts) with respect to ranges and ploidy levels, especially for F. viviparoidea.

Many chromosome counts cannot be assigned to taxa without inspecting the vouchers, especially pre-1981 Greenland reports for F. vivipara s. lat. (Böcher and Larsen 1950, 2n = 28, two counts; Jørgensen et al. 1958, 2n = 28; Holmen 1964, 2n = ca. 63), as all three viviparous species are present in Greenland.

Higher Taxa