Raft Spider
Dolomedes fimbriatus
The raft spider, scientific name Dolomedes fimbriatus, is a large semi-aquatic spider of the family Dolomedidae found throughout north-western and central Europe. It is one of only two species of the genus Dolomedes found in Europe, the other being the slightly larger Dolomedes plantarius which is endangered in the UK.
34
Countries
Photo: Wikimedia Commons (CC) via https://en.wikipedia.org/wiki/Raft_spider
Taxonomy & Classification
Kingdom
Animalia
Phylum
Arthropoda
Class
Arachnida
Order
Araneae
Family
Pisauridae
Genus
Dolomedes
Raft Spider belongs to the family Pisauridae, order Araneae, within the Arachnida class.
Species Profile
The raft spider, scientific name Dolomedes fimbriatus, is a large semi-aquatic spider of the family Dolomedidae found throughout north-western and central Europe. It is one of only two species of the genus Dolomedes found in Europe, the other being the slightly larger Dolomedes plantarius which is endangered in the UK.
The Raft Spider faces severe population declines due to widespread habitat destruction and degradation of wetland ecosystems across its range. Water pollution, drainage of marshlands for agriculture and development, and climate change-induced alterations to water levels have dramatically reduced suitable habitat availability. Conservation status may vary by region or assessment authority, but the species remains highly vulnerable to continued wetland loss.
Key Facts
Habitat & Distribution
Inhabits shallow, nutrient-rich freshwater wetlands including pond margins, ditches, fens, marshes, and slow-moving streams with abundant emergent vegetation. Requires areas with floating vegetation mats and overhanging plants that provide hunting platforms and refuge sites near the water surface.
Threats
IUCN Red List: Critically Endangered
The Raft Spider faces severe population declines due to widespread habitat destruction and degradation of wetland ecosystems across its range. Water pollution, drainage of marshlands for agriculture and development, and climate change-induced alterations to water levels have dramatically reduced suitable habitat availability. Conservation status may vary by region or assessment authority, but the species remains highly vulnerable to continued wetland loss.
Climate change affecting water levels
Water pollution and eutrophication
Wetland habitat destruction and drainage
Agricultural intensification near water bodies
Urban development in riparian zones
Found in 34 Countries
Community Sightings
Report a sightingNo community sightings yet. Be the first to report!
Sources & Attribution
How to Cite
IUCN: IUCN (2025). The IUCN Red List of Threatened Species. Version 2025-1. Available at: https://www.iucnredlist.org. doi:10.2305/IUCN.UK.2025-1.RLTS
GBIF: GBIF.org (2025). GBIF Home Page. Available at: https://www.gbif.org
This page: SpeciesRadar (2025). Raft Spider (Dolomedes fimbriatus). SpeciesRadar: Intelligence for Earth's Biodiversity. Available at: https://speciesradar.org/species/raft-spider