Normandia nitens
Key Details
| Taxonomic Groups: | Invertebrate > insect - beetle (Coleoptera) > Water beetle |
| 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: | Riolus nitens |
| UKSI Recommended Authority: | (Müller, P.W.J., 1817) |
| UKSI Recommended Qualifier: | (none specified) |
| Red List Citation: | Foster, 2010 |
| Notes on taxonomy/listing: | (none) |
Criteria
| Question 1: | Does species need conservation or recovery in England? |
| Response: | Yes |
| Justification: | Riolus nitens has declined catastrophically with adult records now confined to a few sites on the Wye and Teme in the south-west Midlands, though larvae have been reported from some other rivers. |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | Yes |
| Justification: | Riolus nitens is genuinely at risk of extinction in England in the near future, and more so than the other riffle beetles Stenelmis canaliculata and Macronychus quadrituberculatus. While it is vulnerable to catchment-level pressures, largely related to P inputs, targeted monitoring of this species is essential. |
| 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: | No |
| Justification: | Rare habitat specialist |
Species Assessment
| Current step on the Species Recovery Curve (SRC): | 3. National Monitoring Plan agreed and implemented |
| Recovery potential/expectation: | Unknown |
| National Monitoring Resource: | Opportunistic - insufficient |
| Species Comments: | Ad hoc recording as part of GB water beetle recording scheme (Balfour-Browne Club/Aquatic Coleoptera Conservation Trust) |
Key Actions
Key Action 1
Proposed Action: Collate records and publish a 5 yearly assessment of the status of Riolus nitens in England. If insufficient data is available from EA sources, consider carrying out targeted surveys of the Teme and Wye.
Action targets: 3. National Monitoring Plan agreed and implemented
Action type: Status survey/review
Duration: 2 years
Scale of Implementation: Unknown
High priority sites: Rivers Teme and Wye (Worcestershire & Herefordshire)
Comments: Relevant to 2 river catchments
Key Action 2
Proposed Action: Review options for monitoring this species as part of an England threatened riverine invertebrate assemblage. A broad framework is likely to be more efficient than a multitude of single-species monitoring actions. Any such framework should consider EA biological monitoring coverage, and taxa unlikely to be detected by standard kick-sampling methods.
Action targets: 3. National Monitoring Plan agreed and implemented
Action type: Status survey/review
Duration: 3-5 years
Scale of Implementation: Not applicable
High priority sites:
Comments: In the absence of an agreed national framework for monitoring threatened riverine invertebrates, ensure that targeted monitoring of R. nitens is undertaken at regular intervals within its current distribution.
Key Action 3
Proposed Action: Undertake a literature review of the species' ecological requirements to inform river managers and river restoration practitioners. Consider a multi-species project involving other threatened riverine water beetles (perhaps encompassing other river taxa?). This review should enable its audience to understand when standard measures might need to be re-considered and should include a series of species factsheets with distribution maps.
Action targets: 4. Autecology and pressures understood
Action type: Scientific research
Duration: 3-5 years
Scale of Implementation: Not applicable
High priority sites:
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.