Siphlonurus armatus
Key Details
| Taxonomic Groups: | Invertebrate > insect - mayfly (Ephemeroptera) > Mayfly |
| Red List Status: | Endangered (Not Relevant) [EN(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: | Siphlonurus armatus |
| UKSI Recommended Authority: | Eaton, 1870 |
| UKSI Recommended Qualifier: | (none specified) |
| Red List Citation: | Macadam, 2016 |
| Notes on taxonomy/listing: | (none) |
Criteria
| Question 1: | Does species need conservation or recovery in England? |
| Response: | Yes |
| Justification: | This species is considered Endangered in Great Britain. It is currently known from Hertfordshire and Sussex, although was once also found in Middlesex and Cumbria. |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | Yes |
| Justification: | This species is dependent on small temporary watercourses and would benefit from the establishment of further populations in England to reduce the risk of extinction. |
| 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: | This species could benefit from actions to improve water quality, limit abstraction, and mitigate for climate change impacts. |
Species Assessment
| Current step on the Species Recovery Curve (SRC): | 2. Biological status assessment exists |
| Recovery potential/expectation: | Low - Combination or other (detail in comments) |
| National Monitoring Resource: | Combination - insufficient |
| Species Comments: | The watercourses where this species occurs are increasingly under pressure from climate change and abstraction. Water quality may also be a problem for some populations. Conservation translocations recovery could be high but currently untested. Targeted sampling is required in temporary watercourses in Hertfordshire and Sussex. |
Key Actions
Key Action 1
Proposed Action: A thorough survey of temporary watercourses in Hertfordshire and Sussex is required to determine this species status in England.
Action targets: 2. Biological status assessment exists
Action type: Status survey/review
Duration: 1 year
Scale of Implementation: Not applicable
High priority sites: N/A
Comments: Necessary step to inform future translocation
Key Action 2
Proposed Action: Investigate the feasibility of conservation translocations for this species.
Action targets: 5. Remedial action identified
Action type: Ex situ conservation
Duration: 3-5 years
Scale of Implementation: Not applicable
High priority sites: N/A
Comments:
Key Action 3
Proposed Action: Translocation of captive bred population to watercourses identified in Action 2
Action targets: 6. Recovery solutions trialled
Action type: (Re-)introduction
Duration: 3-5 years
Scale of Implementation: ≤ 5 sites
High priority sites: To be determined by Action 1
Comments:
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.