Dolichopus lineatocornis
Key Details
| Taxonomic Groups: | Invertebrate > insect - true fly (Diptera) > Long-legged fly |
| Red List Status: | Vulnerable (Not Relevant) [VU(nr)] |
| D5 Status: | Included in the baseline Red List Index for England (Wilkins, Wilson & Brown, 2022) |
| Section 41 Status: | (not listed) |
| Taxa Included Synonym: | (none) |
| UKSI Recommended Name: | Dolichopus lineatocornis |
| UKSI Recommended Authority: | Zetterstedt, 1843 |
| UKSI Recommended Qualifier: | (none specified) |
| Red List Citation: | Drake, 2018 |
| Notes on taxonomy/listing: | (none) |
Criteria
| Question 1: | Does species need conservation or recovery in England? |
| Response: | Yes |
| Justification: | Only recorded from 6 hectads since 1990, the latest record from East Anglia (Norfolk) 2021, prior to that, a single record from Cambridgeshire in 2016. |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | Yes |
| Justification: | The species has shown a small decline of distribution however it appears that this was never a widespread species. That said the biology is better understood than some other Dolichopus species and the habitat requirements known, allowing for more precise actions in areas that the fly is found. |
| Question 3: | At a landscape scale, would the species benefit from untargeted habitat management to increase habitat mosaics, structural diversity, or particular successional stages? |
| Response: | Yes |
| Justification: | The habitat requirements are fairly broad and landscape scale changes that maintain water levels in general may be useful. Wetland, well vegetated margins of gravel pits/washlands on Tertiary clay in Cambs, previously found by pools, ponds and ditches and in swamp or tall herb fen. |
Species Assessment
| Current step on the Species Recovery Curve (SRC): | 4. Autecology and pressures understood |
| Recovery potential/expectation: | Low - Life history factor/s |
| National Monitoring Resource: | Opportunistic - insufficient |
| Species Comments: | East Anglia appears to be the western edge of it's range so further spread is unlikely. Along with the threat of habitat loss from climate warming further decline may occur. It should be noted that identifying females of the species is extremely difficult to do accurately. |
Key Actions
Key Action 1
Proposed Action: Tailored surveys of habitat in known or potential habitat localities to determine the populations and species distribution, thus identifying areas where D. llineatocornis is present so that further targeted actions can be implemented.
Action targets: 3. National Monitoring Plan agreed and implemented
Action type: Targeted monitoring
Duration: 2 years
Scale of Implementation: ≤ 20 sites
High priority sites: Yorkshire: River Derwent; Cambs, Ouse and Nene Washes
Comments: Surveys of known/potential sites to establish whether still present
Key Action 2
Proposed Action: Management of water margins to preserve their integrity and vegetative structure.
Action targets: 4. Autecology and pressures understood
Action type: Habitat management
Duration: >10 years
Scale of Implementation: ≤ 20 sites
High priority sites: Yorkshire: River Derwent; Cambs, Ouse and Nene Washes with any specific sites discovered within the wider landscape
Comments: Sites with most recent records fall within SSSI's so protection and targeted management should be possible; limiting grazing and introduction of conservation, rotational cutting where necessary may be options.
Key Action 3
Proposed Action: Advice and support for local landowners, farmers and agency staff in areas where populations are confirmed or found.
Action targets: 4. Autecology and pressures understood
Action type: Landscape/catchment/marine management
Duration: >10 years
Scale of Implementation: ≤ 20 sites
High priority sites: Yorkshire: River Derwent; Cambs, Ouse and Nene Washes with any specific sites discovered within the wider landscape
Comments: Liaising with local landowners and farmers in relation to water abstraction, slurry, run-off, cattle drinks and potential of ingress by avermectins, nitrates and other harmful chemicals that may make areas uninhabitable.
Acknowledgment:
Data used on this website are adapted from Threatened species recovery actions 2025 baseline (JP065): Technical report and spreadsheet user guide (Natural England, 2025). Available here.