Taxonomy
Lejogaster tarsata
Distribution
Species Biology
Preferred environment
Freshwater/wetland; clean water streams, springs in fens and spring-fed ponds. Being associated with spring-fed pools and small brooklets, L. tarsata might be expected to be frequent in Ireland. However, it is not found in association with water bodies with cattle-trampled margins, or water eutrophicated by cattle droppings, which would exclude it from the vast majority of otherwise potential locations. The few Irish records are all from wetland situations where livestock are either excluded or exert minimal influence. That most records are from the south-east of the island is probably no co-incidence, because L. tarsata does not extend far into northern Europe - in Norway, for instance, there is but one record from the southern edge of the country - and may be climatically on the edge of its range here.
Adult habitat & habits
Margins of streams and pools, flies in a zigzag, darting fashion, among taller vegetation.
Flight period
Mid May/August, and on to the end of September in southern Europe. Larva: described and figured by Maibach and Goeldlin (1994) and by Hartley (1961), from larvae found among floating, decaying vegetation in a pond and figured in colour by Rotheray (1994).
Flowers visited
White umbellifers; Matricaria, Ranunculus.
Irish reference specimens
In the collections of NMI and UM
Determination
van der Goot (1981). The male terminalia are figured by Maibach et al (1994a). The adult insect is illustrated in colour by Bartsch et al (2009b), Stubbs and Falk (1983) and Torp (1994).This species appears as L. splendida (Mg.) in most recent literature, including van der Goot (1981) and Stubbs and Falk (1983). Maibach et al (1994b) reinstate the name tarsata.
Distribution
World distribution(GBIF)
From Fennoscandia south to the Mediterranean and Mediterranean islands (Corsica, Sicily); from Ireland east through central and southern Europe into European parts of Russia; Iran and Afghanistan and on by way of Uzbekistan, Tajikistan, Kirghizia, Turkmenia and Kazakhstan to Mongolia, south-eastern Siberia and the Pacific coast. The situation of this species in other parts of Europe is varied. While it would justifiably be regarded as threatened in Germany and Switzerland, it does not appear to be so elsewhere.
Irish distribution
Added to the Irish list by Speight (1978c). There are few Irish records of this species, most of them from the south-east. Recent records are all from sites which are provided with some degree of protection, but are so few that L. tarsata has to be categorised as vulnerable in Ireland, if not as endangered.
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.