Horrid Ground-weaver (Nothophantes horridus)
Key Details
| Taxonomic Groups: | Invertebrate > spider (Araneae) > Spider |
| 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: | Nothophantes horridus |
| UKSI Recommended Authority: | Merrett & Stevens, 1995 |
| UKSI Recommended Qualifier: | (none specified) |
| Red List Citation: | Harvey et al., 2017 |
| Notes on taxonomy/listing: | (none) |
Criteria
| Question 1: | Does species need conservation or recovery in England? |
| Response: | Yes |
| Justification: | EN, criteria: B2ab(ii,iii,iv): remains tightly confined to Plymouth area with no substantive change since review. CR on Global Red List because of apparently endemic status, small area of occupancy and, at time of review, apparent decline. |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | Yes |
| Justification: | Appears to be absent from many similar locations |
| 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: | This species would not benefit from untargeted management |
Species Assessment
| Current step on the Species Recovery Curve (SRC): | 4. Autecology and pressures understood |
| Recovery potential/expectation: | Unknown |
| National Monitoring Resource: | Combination - insufficient |
| Species Comments: | Apparently endemic, troglophilic in limestone fissures. Nocturnal and largely winter active usually found in quite seedy areas of its largely urban environment, including under rubbish on suburban road verges. Current level of annual survey probably sufficient but search further afield required. |
Key Actions
Key Action 1
Proposed Action: Target survey of other limestone areas/quarries in SW England using current knowledge of effective survey methods
Action targets: 2. Biological status assessment exists
Action type: Status survey/review
Duration: 2 years
Scale of Implementation: Not applicable
High priority sites: Plymouth area, Mendips
Comments: Use most recent improvements in survey methods
Key Action 2
Proposed Action: Check expanding international bar code/genome sequence datasets for matches to help confirm/refute endemic status, especially given that a major port city appears to be sole GB location
Action targets: 3. National Monitoring Plan agreed and implemented
Action type: Targeted monitoring
Duration: >10 years
Scale of Implementation: ≤ 5 sites
High priority sites: Plymouth sites
Comments:
Key Action 3
Proposed Action: Consider the full range of measures available to improve site safeguard at all recent (and any new) Plymouth locations, particularly Radford Quarry CWS which is currently the subject of a new housing development proposal. On urban verges sites explore potential local Council options.
Action targets: 5. Remedial action identified
Action type: Site protection
Duration: 2 years
Scale of Implementation: ≤ 5 sites
High priority sites:
Comments: Particularly in the absence of further discoveries, needed to protect entirety of this endemic's known range from quarrying, urban/industrial development and public pressure
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.