Hammerschmidtia ferruginea - The Aspen Hoverfly

Hammerschmidtia ferruginea

Name: Hammerschmidtia ferruginea (Fallén, 1817)

Family: Syrphidae

Common name: Aspen Hoverfly

Distribution

European distribution

H. ferruginea is rare and thought to be endangered in Europe. It is an indicator of ancient woodlands of international importance in Europe.

See Fauna Europaea for country-level information.

British distribution

In 1990-93, H. ferruginea was known from eight sites in the British Isles. Intensive survey throughout Scotland during 1990-3, including all previous locations, extended its known distribution to 12 sites in 8 ten km squares in the north-east of Scotland. The main stronghold is Strathspey between Newtonmore in the south and Grantown in the north. Other sites are in the valley of the Findhorn, Easter Ross, Wester Ross, south-east Sutherland and Deeside.

Distribution maps

Distribution map from publicly available, 10km square resolution data on the NBN Gateway.

Distribution map from the Hoverfly Recording Scheme

Ecology

The larvae of Hammerschmidtia ferruginea are found in wet decaying cambium that builds up under the bark of recently fallen or dead standing trees, and large branches of aspen with a diameter of at least 30 cm. Wet decaying cambium builds up for about four years in any one branch or tree before the bark cracks and it dries out. Population sizes have never been monitored, but the number of larvae present in individual pieces of fallen wood is generally under 50, and they may be vulnerable to over collecting. Only aspen stands which extend over 4.5 ha are large enough to maintain the continuity of fresh inputs of suitably sized fallen timber needed for H. ferruginea. Most aspen stands in Scotland are small, less than 1.5 ha. In the Highlands, only 14 aspen stands extend over 4.5 ha and H. ferruginea is virtually absent from the numerous smaller stands, particularly those beyond 1 km of the core stands. Adults fly in late May to July, with the peak in June. They are generally found on or around Aspen occurring on stumps, trunks and fallen timber. They occasionally visit flowers and have been observed on flowers of rose and Rowan and also basking on sunny vegetation along the edges of Aspen stands.

Habitat

Stands of mature Aspen in the Scottish Highlands that are of at least 4.5Ha in extent and in which there is continuity of supply of freshly fallen Aspen trunks or large branches of at least 30cm in diameter.

Sources of information

Links

BAP

Existing BAP species

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bap/existing/hammerschmidtia_ferruginea.txt · Last modified: 2008/04/22 23:58 (external edit)     Back to top
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