Dragonfly species in Monmouthshire: White-legged Damselfly

Distribution map of White-legged Damselfly in Monmouthshire, March 2024
Distribution map of White-legged Damselfly in Monmouthshire, March 2024, produced using the DMAP for Windows software written by Alan Morton, www.dmap.co.uk

White-legged Damselfly (Platycnemis pennipes) is a localised damselfly in Monmouthshire, mainly confined to slower flowing rivers.

The oldest record in our data set is from the River Wye at Bigsweir, on 24 June 1975 (observer John Paul).

Current distribution in the county: what we know

Post-2019 records come from two areas: the River Wye and its tributary the Monnow, and the River Usk and its tributary the Olway Brook. The White-legged Damselfly population on the Wye extends upstream of Monmouth to the county boundary and beyond, and downstream at least as far as Bigsweir, with occasional records from Tintern Old Station. At least the lowest few kilometres of the Monnow also support this species. On the Usk, White-legged Damselfly has been recorded from Abergavenny downstream to the river’s tidal limit at Newbridge-on-Usk, albeit with some large gaps in its occurrence. It was found on the Olway Brook for the first time in 2023.

Current distribution in the county: what we don’t know

White-legged Damselfly probably occurs almost entirely on these two river systems; the rivers in the west of the county are too fast-flowing for this species. Further recording on the Usk and the Wye would be useful, to understand whether it is present in the areas which currently lack records, to establish the lower and upper limits on each river, and also to assess the effect of the ongoing severe agricultural pollution. On the Monnow, there are older records from stretches upstream as far as Grosmont, and recording here will be helpful to determine if it is still present. It is possible that White-legged Damselfly also occurs on further tributaries: the Trothy River may repay visits, for example.

Distribution elsewhere

White-legged Damselfly is a scarce and localised species in Wales. It is present on the Wye as far upriver as the Rhayader area, but on the Usk it has not been recorded beyond Abergavenny; further north it occurs on the Severn from Newtown to the English border. It is a much more widespread species in England, being found widely in the southwest, the southeast and the Midlands, but it is absent from northern England and from Scotland. Elsewhere in Europe, it is found from France east to Russia, north to southern Sweden and Finland, and south to Italy and Greece; its range continues east in Asia from Turkey to Siberia.