Новый вид Saussurea trufanovae (Asteraceae) из Северо-Западной Якутии

<jats:p>The collection of the SASY Herbarium (Yakutsk) revealed 4 specimens of Saussurea tilesii (Ledeb.) Ledeb. from the Olenyok River basin, collected by Ye. R. Trufanova in August 1979. The plants habitus (including the height of the stems) is close to boreal species Saussurea stubendorffii Herd. But other, more comprehensicve signs, such as the shape of the spathe leaflets, their position, and the cobwebby pubescence of the lower surface of the leaves, are more consistent with S. tilesii, which is widespread in tundra and mountainous areas. Obviously, the plants collected by Ye. R. Trufanova occupy an intermediate position between S. tilesii and S. stubendorffii, noticeably differing from both known taxa. Considering that such forms are often found in the river valleys of Northwest Yakutia, it is proposed to isolate them into a separate species, named by their first collector: Saussurea trufanovae E. G. Nikolin et N. K. Sosina sp. nova. This species differs from S. tilesii by a significant stem height (to 45-50 cm), a spreading inflorescence with numerous, slightly deflected branches to 25 cm long, bearing corymbs with 3-8 baskets assembled into loose heads. It differs from another closely related species S. stubendorffii by the implicit tengularity of the spathe with elongated leaflets, branching of the stem, and cobwebbed (not grayish-pannose) pubescence of the lower surface of the leaves.</jats:p>