© Ralph Forbes
Map updated: March 2008
| Species Description: |
| Resembling a Potamogeton species, but with opposite, not alternate, leaves. This is a totally-submerged pondweed of base-rich lakes. The only Northern Ireland site is Lough-na-Trosk in Co. Antrim, where it was discovered in 1971. This lake sits in a basin below some basaltic cliffs at about 290 metres altitude and has an alkaline pH. Two dots appear on the map because the lake falls within two adjacent hectads. |
| All names: Groenlandia densa (L.) Fourr.; Potamogeton densus L. |
| © National Museums Northern Ireland, 2000-2009 |