Abstract

The Cheshire Hoverfly Orthonevra intermedia is a rare wetland species in Britain, currently known only from a restricted area of the Cheshire Plain. This report presents the results of a baseline survey undertaken in 2022 to assess its distribution, habitat use and status within Delamere Forest and the Abbots Moss Complex. Targeted fieldwork was conducted on basin mires during the species’ anticipated flight period, supplemented by desk-based collation of historical and unpublished records. O. intermedia was recorded from eight mire sites during the survey, confirming its continued presence and apparent strong association with Sphagnum-dominated floating bog habitats. Most records comprised males observed flying low over, or settling on, Sphagnum mats. The results indicate that the species is more widespread within suitable mire systems in the study area than previously documented. The report provides an updated synthesis of British records, outlines key habitat requirements, and discusses implications for future monitoring, conservation management and further research.

Appendix 2: Data spreadsheet

#Diptera Ref. True Flies

Published 19th December 2025