Panarctic Flora

421216-18 The Silene involucrata aggregate S. involucrata, S. ostenfeldii, S. sorensenis

Geography: Circumboreal-polar.

Notes: Elven, Murray, and Petrovsky: The Silene involucrata aggregate is characterized by, e.g., narrow-winged or unwinged seeds and well emerging, white or more rarely slightly pink petals. It includes large-seeded tetraploids - by Tzvelev (2000b) treated in Russia as a series of three species, by us as one species, Silene involucrata, with three subspecies - and small-seeded hexaploids that we consider as two species: S. ostenfeldii and S. sorensenis.

This aggregate has support from molecular evidence. Popp et al. (2005) showed that its species are results of at least two probably comparatively ancient hybridizations and polyploidizations between species from the diploid S. uralensis lineage and the diploid S. linnaeana (Lychnis sibirica) lineage. Silene involucrata is one or more tetraploids from one or more crosses between the primary lineages, and both S. sorensenis and S. ostenfeldii are hexaploids from one or probably two crosses between this derived lineage and the S. linnaeana lineage. It has not yet been established whether the different parts (subspecies) of S. involucrata are due to divergence posterior to the polyploidization or to different polyploidization events.

There is a plethora of epithets in the S. involucrata aggregate, based on the following names presented in chronological order: (1) Lychnis pauciflora Ledeb. 1815, probably described from Yakutia in Siberia; (2) Lychnis triflora R. Br. ex Sommerf. 1824, described from Greenland; (3) Lychnis apetala var. involucrata Cham. & Schltdl. 1826 and Agrostemma involucrata (Cham. & Schltdl.) G. Don 1831, described from eastern Siberia and/or the Russian Far East; (4) Silene furcata Raf. 1840, described from the Hudson Bay-Labrador area in Canada; (5) Lychnis affinis J. Vahl ex Fr. 1842, described from northern Norway; (6) Wahlbergella and Gastrolychnis angustiflora Rupr. 1845, described from Kolguev in northeastern European Russia; (7) Gastrolychnis vahlii Rupr. 1845, a nomen novum for Lychnis affinis; (8) Lychnis taylorae B.L. Rob. & Seaton 1893, described from the Mackenzie River Delta (N.W.T.) in Canada; (9) Melandrium taimyrense Tolm. 1932, described from Taimyr in Siberia; (10) Melandrium affine subsp. tenellum Tolm. 1932, described from the northern Jenisei River area in Siberia; (11) Melandrium gracile Tolm. 1932, described from the Kemkem River basin in Yakutia, Siberia; (12) Melandrium ostenfeldii A.E. Porsild 1943, described from Great Bear Lake (N.W.T.) in Canada; (13) Lychnis triflora var. dawsonii B.L. Rob. 1893 and Melandrium dawsonii (B.L. Rob.) Hultén 1944, described from British Columbia in Canada; and (14) Lychnis sorensenis B. Boivin 1951, described from Greenland. The two oldest specific epithets in this aggregate - "pauciflora" and "triflora" - are inapplicable in Silene due to homonymy. Except for Melandrium gracile, we have tried to sort these names on taxa below.

Kovtonyuk (1993a) accepted Melandrium gracile Tolm., Trudy Bot. Muz. 24: 261 (1932) [Gastrolychnis gracilis (Tolm.) Czerep., Sosud. Rast. SSSR: 161 (1981)] and reported it to reach the Arctic in Yakutia. Czerepanov (1981) indicated possible synonymy with Gastrolychnis taimyrensis but it is not clear what he meant by the name "taimyrensis" (see S. involucrata subsp. involucrata below). The data available are too few for evaluation and assignment of this name and putative taxon.