| Sonchus arvensis var. glabrescens Günth., Grab. & Wimm. | |
| Publ. & Syn. | Sonchus uliginosus M. Bieb., Fl. Taur.-Caucas. 2: 238 (1808). Described from the Caucasus. - Sonchus arvensis subsp. uliginosus (M. Bieb.) Nyman, Consp. Fl. Eur. 2: 433 (1879). |
| Notes | The tetraploid taxon - Sonchus uliginosus, S. arvensis subsp. uliginosus, or S. arvensis var. glabrescens - differs from S. arvensis s. str. in being glabrous (vs. with abundant glandular hairs) even in the inflorescence, perhaps also in a few other features. Intermediates towards S. arvensis s. str. are documented. It is largely sympatric with S. arvensis s. str. Rank as species might be appropriate if the ploidy difference can be fully substantiated. Arctic records are dubious. Scoggan (1979) reported it from Churchill on Hudson Bay in Manitoba (as var. glabrescens), most probably as adventive. The specimens we have seen from northern Canada (CAN, DAO) do, however, not belong to var. glabrescens on morphological criteria, but rather to S. arvensis s. str. |
| Chromosomes | 36 (4x). - Europe, Canada. - Numerous reports, partly for S. arvensis. |
| Geography | European - Asian: CAN*. |
| Distribution | N = * E = * HL = * [ key ] |
| Parent taxon | Sonchus arvensis L. |
| PAF ID | 863701b |