Taxonomy
Platycheirus ramsarensis
Distribution
Species Biology
Preferred environment
Wetland/open ground; tundra, transition mires, flushes in blanket bog, lakeside vegetation round oligotrophic lakes and with tall, marginal vegetation along brooks in moorland and oligotrophic, unimproved, montane grassland on non-calcareous soils. P. ramsarensis is a western and upland syrphid in Ireland. It occurs among tall marginal vegetation (e.g. Juncus) along streams in moor and blanket bog. It may also be found where tall ground vegetation occurs in base-rich flushes in blanket bog, with flushes in unimproved, upland grassland, in transition mires and in cutover blanket bog where pools with tall marginal vegetation have formed. It is more a species of mire than bog and in Scandinavia occurs into the far north in tundra. The combination of standard farmland (green fields plus hedges) and conifer plantations, that occupies most of the surface of Ireland today, does not provide any suitable habitat for P. ramsarensis. But the devastation visited upon the uplands in western Ireland, by overgrazing by sheep, which has been especially severe during the last decade, has probably had less effect upon P. ramsarensis than on the related P. podagratus, because P. ramsarensis is more associated with unpalatable Juncus than is P. podagratus.
Adult habitat & habits
Flies among Juncus etc. and is as easily detected by use of a sweep net as by direct observation.
Flight period
End of June/mid August, with peak in mid-July. Males have so far only been collected in the period June/ beginning July. Larva: not described.
Flowers visited
Caltha palustris; probably also Graminae and Cyperaceae.
Irish reference specimens
In the collections of NMI and UM
Determination
Males of P. ramsarensis are less easily recognised than the females, a situation unusual among Platycheirus species. Males of P. angustatus in which microtrichial coverage of the wings is complete are particularly easy to confuse with P. ramsarensis. The male terminalia are figured by Goeldlin et al (1990). In its general appearance, the female can easily be mistaken for P. clypeatus, P. immarginatus or P. occultus. P. ramsarensis may be distinguished from these other species by means of the keys given in Speight and Goeldlin (1990), Haarto and Kerppola (2007a) and Bartsch et al (2009a). The adult insect is illustrated in colour by Bartsch et al (2009a). However, the facial shape has proved to be more variable in male P. ramsarensis than is indicated in the key provided by Speight and Goeldlin (1990) and cannot be used to distinguish this species. The front leg features referred to by Stubbs (1996) are easier to use for separation of males of P. ramsarensis. It is not unusual to find P. ramsarensis on the wing in the company of P. angustatus, P. occultus, P. clypeatus and P. scambus. This species is also included in the keys provided by van Veen (2004).
Distribution
World distribution(GBIF)
As yet known only from the Faroes (Jensen, 2001), Scandinavia (northern Norway to the southern tip of Norway, Finland), Ireland, the Outer Hebrides and Britain (Scottish Highlands south to Yorkshire). This is essentially a northern European syrphid, occurring in western and upland parts of Britain and Ireland, but otherwise not yet known south of Scandinavia. It remains to be established whether the range of P. ramsarensis extends eastwards beyond Scandinavia, into Siberia, but this would seem likely. If not, then this species has a more restricted world range than most other syrphids known in Ireland.
Irish distribution
Added to the Irish list by Goeldlin et al (1990). This species was unrecognised prior to that date, having been confused with other closely similar members of the clypeatus group which also occur in Ireland. The type locality for P. ramsarensis is in Ireland and the species was named in honour of the Ramsar Convention which, in the year that this species was described, redefined its charter to cover all wetland organisms, having been concerned previously primarily with conservation of wetland birds.
Distribution frequency in Ireland
In Ireland, P. ramsarensis is almost confined to the western half of the island. It is not infrequent, but is nonetheless rather localised.
Temporal change
Records submitted to Data Centre in 2025
The following map is interactive. If you would prefer to view it full screen then click here.
References
Publications
Speight, M. C. D. (2008) Database of Irish Syrphidae
(Diptera). Irish Wildlife Manuals, No. 36. National Parks and Wildlife Service.
Department of Environment, Heritage and Local Government, Dublin, Ireland.
Speight, M.C.D. (2014) Species accounts of European
Syrphidae (Diptera), 2014. Syrph the Net, the database of European Syrphidae,
vol. 78, 321 pp., Syrph the Net publications, Dublin.