Lichen Running Spider
Fast Facts
Latin name: Philodromus margaritatus
Notable feature: The Lichen Running Spider is a master of disguise, seamlessly blending into their surroundings.
Conservation Status: Near Threatened
Where in the UK: Southern England and central Scotland.
Lichen Running Spider (Philodromus margaritatus) © John Walters
The Lichen Running Spider (Philodromus margaritatus) is a native species to the UK and has a rather flattened appearance, belonging to the Crab Running Spider family. The spiders’ colouration and markings are incredibly variable. They are experts of disguise, often matching and blending in with their surrounding habitat, providing excellent camouflage.
Generally, this species is white to greenish in colour, and often mottled in appearance, matching the lichen which they are named after.
Unlike web building species of spider, the Lichen Running Spider is an active hunter, and it actively searches for its prey. It hunts along tree trunks and branches, using its speed to catch small insects.
The Lichen Running Spider is found on trunks of mature trees, both broadleaved and coniferous species, especially where they are covered in lichen. The spider prefers slightly more open areas of woodlands, such as clearings, rather than closed canopy areas. It has even been found in old apple orchards where lichen covers the trunks. There are also records from electricity pylons near pine forests.
- Size: 4 to 6 mm long.
- Life span: Unknown.
- Diet: Small insects.
- Reproduction: The females lay their eggs in a silk sac. Like the adults, the spiderlings are well camouflaged.
- When to see: Males are active from March to July, and females from April to September. Data on this spider is limited, due to its Nationally Rare status.
- Population Trend: There has been a 33% decline, based on data from the 2017 GB Spider Status review.
- Threats: Habitat loss, due to the felling of lichen-covered trees, degradation of woodlands supporting these trees, and Ash Dieback disease.
- Interesting Fact: The Lichen Running Spider belongs to the Crab Running Spider family. The name comes from the crab-like body shape the spiders in this family have and their long legs allowing for speedy movements to catch their prey along tree branches.
How you can help:
If you think you have spotted a Lichen Running Spider, share you finds by submitting a record to the Spider Recording Scheme on iRecord: BAS recording schemes record entry form.
Buglife work to increase awareness of invertebrates and support nature’s recovery through our projects and campaigns, but we need your help! In 2026, Buglife kicked off the Moor Invertebrates Project, aiming to secure the future of eight threatened invertebrate species within the Dartmoor Important Invertebrate Area and in Dartmoor National Park – including the Lichen Running Spider.
This project, and others like it, rely on donations and member support to continue our work. If you searched, found and learned about our incredible invertebrates on our website, please consider donating to Buglife, joining our community or even buying from our shop. For more ideas on how to support our work find out how to Get Involved. Thank you 🕷
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