| Carex demissa Hornem. | |
| Publ. & Syn. | Carex oederi subsp. oedocarpa Andersson, Pl. Scand 1: 25 (1849). Described from Scandinavia. - Carex viridula subsp. oedocarpa (Andersson) B. Schmid, Watsonia 14: 316 (1983). |
| Notes | Elven and Solstad: The main range of Carex demissa is in mainland Europe but it does not reach the Arctic there. We have seen a few specimens of indubitable C. demissa from the Arctic in Iceland (ICEL) and southern Greenland (O). Crins (2002b, as C. viridula subsp. oedocarpa) did not accept the species from Greenland and indicated it probably to have been introduced in North America. The southern Greenland plant is most probably native. Carex demissa is, in our opinion, a morphologically distinct species and reproductivelly isolated from C. viridula. Pykälä and Toivonen (1994) concluded in the same way. In addition to several assumed independently inherited characters in leaves, stems, spikes, and perigynia, and pollen and fruit sterility in plants morphologically identified as hybrids, it differs from all the other northwestern European taxa of this group in prefering less basic or often acidic substrates and often ruderal or disturbed sites. Ball: It still can occur adjacent to other members of the section and can then produce putative hybrids. Elven: This is certainly the case in northwestern Europe where it seems to hybridize extensively with C. flava wherever they co-occur, frequently with C. viridula and C. lepidocarpa, and occasionally with as morphologically distant a species as C. hostiana. All putative C. demissa hybrids are largely or fully pollen and fruit sterile. Occurrence of hybridization by itself, without taking hybrid fertility into account, is not a reliable indication of conspecificity. |
| Chromosomes | 70. - Europe. - Several reports. A report of 2n = 70 from southern Greenland (Jørgensen et al. 1958) may belong here. |
| Geography | Amphi-Atlantic (E) - European: ICE GRL. |
| Distribution | N = S GW = r Ic = r E = R [ key ] |
| Parent taxon | Carex L. |
| PAF ID | 3309023 |