Xysticus robustus
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: | Bassaniodes robustus |
| UKSI Recommended Authority: | (Hahn, 1832) |
| 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,iv): threat status may increase at next review. All records restricted to the S coast of England and found in only one of its former 10 hectads since 2000, despite increased survey effort in its Dorset/Hants. heaths stronghold. |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | Yes |
| Justification: | Extreme rarity is not consistent with availability of apparently suitable habitat |
| 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): | 2. Biological status assessment exists |
| Recovery potential/expectation: | Unknown |
| National Monitoring Resource: | Opportunistic - insufficient |
| Species Comments: | Specialist of dry heathland and coastal calcareous grassland, usually in stony, sparsely vegetated areas among older, taller vegetation |
Key Actions
Key Action 1
Proposed Action: Targeted survey of all recorded, nearby and apparently suitable sites, using standardised methodology to assess current status (and establish baseline for national monitoring programme)
Action targets: 2. Biological status assessment exists
Action type: Status survey/review
Duration: 2 years
Scale of Implementation: ≤ 10 sites
High priority sites: Dorset/Hampshire heaths; Sugar Loaf Hill, Folkstone
Comments:
Key Action 2
Proposed Action: Autecological research to establish microhabitat requirements and inform management
Action targets: 4. Autecology and pressures understood
Action type: Scientific research
Duration: 3-5 years
Scale of Implementation: 1 site
High priority sites: Beaulieu Heath, Hants.
Comments: Only current possibility to attempt this at Beaulieu Heath, where the species was most recently recorded (2018)
Key Action 3
Proposed Action: Produce a spotting card for staff/biologists/visitors to target areas to raise awareness and generate new sightings of this very rarely recorded species.
Action targets: 2. Biological status assessment exists
Action type: Education/awareness raising
Duration: 3-5 years
Scale of Implementation: ≤ 10 sites
High priority sites:
Comments: Viable action for this conspicuous species and combines opportunity to raise awareness with the urgent need to generate sighting opportunities for status re-assessment. BAS to produce, in collaboration with New Forest National Park Authority and other relevant site managers. Data to be fed to SRS via QR code for its iRecord form. In New Forest, action can be combined with that for Xysticus lutator.
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.