Systenus tener
Key Details
| Taxonomic Groups: | Invertebrate > insect - true fly (Diptera) > Long-legged fly |
| Red List Status: | Near Threatened (Not Relevant) [NT(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: | Systenus tener |
| UKSI Recommended Authority: | Loew, 1859 |
| UKSI Recommended Qualifier: | (none specified) |
| Red List Citation: | Drake, 2018 |
| Notes on taxonomy/listing: | (none) |
Criteria
| Question 1: | Does species need conservation or recovery in England? |
| Response: | No |
| Justification: | Six records from three sites since 2014, from Herefordshire (2014), East Sussex (2018) & Hampshire (2019). The distribution mirrors that prior to 2014 and previously it was only recorded from four hectads. Habitat requirements have been outlined and association to rotholes and specific tree families. Drake (2018) suggests that there is a risk of this species being under-recorded and previous doubts on taxonomic status may have affected the accuracy of past assessments. |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | No |
| Justification: | Six records from three sites since 2014, from Herefordshire (2014), East Sussex (2018) & Hampshire (2019). The distribution mirrors that prior to 2014 and previously it was only recorded from four hectads. Habitat requirements have been outlined and association to rotholes and specific tree families. Drake (2018) suggests that there is a risk of this species being under-recorded and previous doubts on taxonomic status may have affected the accuracy of past assessments. |
| 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: | Recovery, if under-recording is not responsible for the lack of records, would be more dependant on habitat management and preservation within suitable habitats such as ancient woodland, park land and retaining the required old, dead or decaying trees. |
Species Assessment
Not relevant as no Key Actions defined.
Key Actions
No Key Actions Defined
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.