Drassodes

Distinguished from other Gnaphosidae genera by their flattened body form adapted for living under stones and bark. The eye arrangement and spinneret structure are characteristic of the family, though specific identification to species level requires examination of genitalia.

Brown, gray, or reddish spiders with elongated bodies. Most species range from 3.8 to 11.6 mm in length, with some individuals reaching up to 20 mm. The overall coloration is cryptic, matching their substrate habitat.

Dry habitats including rocky areas, scree slopes, and woodland edges. Found specifically under stones, beneath bark, and in similar sheltered microhabitats that provide darkness and moisture retention.

Widely distributed across the Northern Hemisphere including Europe (Denmark, Norway, Sweden confirmed), Asia, and North America. The genus shows a broad temperate distribution pattern.

Nocturnal hunters that remain concealed under cover during daylight hours. They emerge from retreats to actively pursue prey rather than building capture webs.

Predatory component of ground-dwelling arthropod communities in dry, rocky ecosystems. Contributes to population regulation of small invertebrates in these habitats.

Generally harmless to humans. Occasionally encountered by hikers or rock collectors when stones are overturned. Not known as a significant pest or beneficial species in agricultural contexts.

• GnaphosaAnother large genus in Gnaphosidae with similar ground-dwelling habits, but typically differs in body proportions and habitat preferences (more open ground vs. under-cover specialists)
• ZelotesSmaller ground spiders in the same family, usually with more uniform dark coloration and different eye arrangement

• ground spider
• nocturnal
• rock-dwelling
• cryptic coloration
• Gnaphosidae

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life