ENEndangered

knopphodeedderkopp

Walckenaeria nodosa

The knopphodeedderkopp (Walckenaeria nodosa) is a tiny sheet weaver spider characterized by distinctive nodular projections on the male's cephalothorax that give the species its common name. These minute spiders construct delicate sheet webs in leaf litter and low vegetation, playing a crucial role as predators of small arthropods including springtails, aphids, and other micro-invertebrates in their ecosystem.

18

Countries

01Classification

Taxonomy & Classification

Kingdom

Animalia

Phylum

Arthropoda

Class

Arachnida

Order

Araneae

Family

Linyphiidae

Genus

Walckenaeria

knopphodeedderkopp belongs to the family Linyphiidae, order Araneae, within the Arachnida class.

02Description

Species Profile

The knopphodeedderkopp (Walckenaeria nodosa) is a tiny sheet weaver spider characterized by distinctive nodular projections on the male's cephalothorax that give the species its common name. These minute spiders construct delicate sheet webs in leaf litter and low vegetation, playing a crucial role as predators of small arthropods including springtails, aphids, and other micro-invertebrates in their ecosystem.

Walckenaeria nodosa faces significant threats from habitat loss and degradation due to agricultural intensification and urban development in its limited range. Climate change and associated shifts in microhabitat conditions pose additional risks to this specialized spider species with restricted distribution.

Key Facts

IUCN StatusEndangered (EN)
GroupArachnids
03Habitat

Habitat & Distribution

Walckenaeria nodosa inhabits the interface between soil surface and low vegetation, particularly favoring areas with dense leaf litter, moss cushions, and the bases of grasses in humid woodland edges and grassland margins. The species requires stable microclimatic conditions with consistent moisture levels and protection from direct sunlight.

04Threats

Threats

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IUCN Red List: Endangered

Walckenaeria nodosa faces significant threats from habitat loss and degradation due to agricultural intensification and urban development in its limited range. Climate change and associated shifts in microhabitat conditions pose additional risks to this specialized spider species with restricted distribution.

Habitat loss from agricultural intensification

HighOngoing

Small population size and restricted range

HighOngoing

Urban development and land conversion

HighOngoing

Climate change affecting microhabitat conditions

MediumOngoing

Pollution and pesticide use

MediumOngoing
Community

Community Sightings

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07Sources

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). knopphodeedderkopp (Walckenaeria nodosa). SpeciesRadar: Intelligence for Earth's Biodiversity. Available at: https://speciesradar.org/species/knopphodeedderkopp

Full citation guide & data usage terms