Petalwort (Petalophyllum ralfsii)
Key Details
| Taxonomic Groups: | Non-vascular plant (incl. chromists) > liverwort > Liverwort |
| 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: | Petalophyllum ralfsii |
| UKSI Recommended Authority: | (Wils.) Nees & Gottsche |
| UKSI Recommended Qualifier: | (none specified) |
| Red List Citation: | Callaghan, 2023 |
| Notes on taxonomy/listing: | (none) |
Criteria
| Question 1: | Does species need conservation or recovery in England? |
| Response: | Yes |
| Justification: | At risk of extinction in England due to small population size and decline |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | Yes |
| Justification: | Work is required to better understand the effectiveness of current management approaches and experimental trials are required to help develop effective habitat restoration solutions |
| 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: | The species has a restricted distribution and so is unlikely to benefit from untargeted actions |
Species Assessment
| Current step on the Species Recovery Curve (SRC): | 6. Recovery solutions trialled |
| Recovery potential/expectation: | Unknown |
| National Monitoring Resource: | Opportunistic - insufficient |
| Species Comments: | GB RL criteria: A2a, C2a(i). Mediterranean Oceanic species. |
Key Actions
Key Action 1
Proposed Action: Develop and implement national monitoring plan to ensure comprehensive and up-to-date information is available on range size, population size, occupied sites and threatening factors in England
Action targets: 3. National Monitoring Plan agreed and implemented
Action type: Targeted monitoring
Duration: 1 year
Scale of Implementation: ≤ 10 sites
High priority sites:
Comments: A species with low recovery potential where the main aim is to maintain/protect populations
Key Action 2
Proposed Action: Evaluate current habitat management approaches to conserving this species, and undertake experimental trials at occupied sites to develop effective habitat restoration solutions.
Action targets: 6. Recovery solutions trialled
Action type: Scientific research
Duration: 3-5 years
Scale of Implementation: ≤ 10 sites
High priority sites:
Comments: Various recent habitat management approaches have been undertaken at various sites, but their effectiveness at promoting recovery of this species has generally been poorly monitored, if at all. Work is required to better understand the effectiveness of current management approaches and experimental trials are required to help develop effective habitat restoration solutions.
Key Action 3
Proposed Action: Provide advice to land managers on locations occupied by the species and its habitat management requirements.
Action targets: 5. Remedial action identified
Action type: Advice & support
Duration: 1 year
Scale of Implementation: ≤ 10 sites
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.