| Notes | Brochmann, Zhmylev, and Elven: Saxifraga svalbardensis is, as far as known, a hybrid species from S. cernua and S. rivularis (Øvstedal 1988; Brochmann et al. 1998). It has been considered restriced to Svalbard but there is at least one old herbarium specimen documenting it also from Russian Novaya Zemlya (1921, TROM). It is probably overlooked in Russian material. In Svalbard, it is frequent and widespread and morphologically homogeneous with several features separating it from both the proposed parents: abundant runners (much thinner and longer than in S. rivularis), fewer and paler bulbils, different leaf shape, and half-closed flowers with petals of irregular size and with lilac stripes. Its principal site type differs from those of both parents as it mainly grown in wet, mossy marshes and mires. We accept a species. Other hybrids are known with the same assumed parentage (e.g., S. opdalensis A. Blytt from southern Norway) but not from the Arctic and with very different site preferences and combinations of morphological features (i.e., absence of runners and with petals regular and without lilac stripes. |