Taxonomy

Anasimyia lunulata

Distribution

Species Biology

Preferred environment

Wetland; margins of dystrophic lakes, ponds and pools with amphibious vegetation, e.g. Menyanthes, usually in valley bogs and transition mires; taiga wetlands. In Ireland A.lunulata is to be found in blanket bog (where it occurs in association with extensive flush systems), round the periphery of valley bogs and in pools and drainage ditches on cut-over bogs where the ground-water is once again influencing their biological character. It is also to be found in large numbers on transition mires, epitomised by Scraw Bog (Westmeath), and poor fen. Lake-margin communities, in which Scirpus predominates, may also support A.lunulata and on the Shannon floodplain the species occurs in spring-fed drainage ditches still subject to annual winter flooding. It is thus a strongly anthropophobic species and can only be expected to decrease in frequency as processes of general land surface drainage, eutrophication of surface water and peat exploitation continue.

Adult habitat & habits

Flies low among vegetation in the immediate vicinity of standing water or out over the water surface among floating vegetation; rarely found more than a few metres from the water's edge; often settles on leaves protruding from the water, such as those of Menyanthes, with which this fly is often found; can be abundant on cut-over bogs where the vegetation is now regenerating.

Flight period

Mid May/end August, with most records from June/July. Larva: aquatic; requires redescription - Hartley's (1961) account may refer to the larva of A.interpuncta, or may be based on both A.interpuncta and A.lunulata.

Flowers visited

White umbels, Caltha, Menyanthes, Ranunculus.

Irish reference specimens

In the collections of NMI and UM

Determination

Bartsch et al (2009b); Verlinden (1991). See Key provided in StN Keys volume. The male terminalia are figured in Claussen & Torp (1980), Speight (1981b), Torp (1984) and van der Goot (1981). The adult insect is figured in colour in Bartsch et al (2009b), Torp (1984, 1994) and van der Goot (1986).

Distribution

World distribution(GBIF)

Scandinavia south to northern France (Haute Saone); Ireland and Britain; European Russia; range elsewhere requires reconfirmation, due to confusion with A.interpuncta.  This syrphid is endemic to Europe.

Irish distribution

Recorded as occurring in Ireland in Coe (1953), but at that point in time A.lunulata was confused with A.interpuncta (Harris). The presence of A.lunulata in Ireland was confirmed by Speight (1981a). A.interpuncta has not so far been recorded from Ireland but its presence here would not be unexpected. A.lunulata is recorded from most parts of Ireland and available information suggests that the species may be more frequent here than elsewhere in Europe. But even so it cannot be regarded as common in Ireland and, though not as yet threatened, it could move into the threatened category soon, given the rate at which appropriate habitat is being lost. 

Temporal change

Records submitted to Data Centre in 2024

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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.

Images