Brown Cobblestone Lichen vs Cobweb spider

Acarospora fuscata compared with Enoplognatha thoracica

Key Differences

Brown Cobblestone Lichen is Least Concern while Cobweb spider is Vulnerable.

Taxonomic Classification

Rank	Brown Cobblestone Lichen	Cobweb spider
Kingdom	Fungi (Fungi)	Animalia (Animals)
Phylum	Ascomycota (Sac Fungi)	Arthropoda (Arthropods)
Class	Lecanoromycetes (Lecanoromycetes)	Arachnida (Arachnids)
Order	Acarosporales (Acarosporales)	Araneae (Araneae)
Family	Acarosporaceae	Theridiidae
Genus	Acarospora	Enoplognatha
Species	Acarospora fuscata	Enoplognatha thoracica

Conservation Status

Brown Cobblestone Lichen

LC — Least Concern

Cobweb spider

VU — Vulnerable

Physical Characteristics

Attribute	Brown Cobblestone Lichen	Cobweb spider
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Brown Cobblestone Lichen

Habitat

Native to Europe and North America, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, Portugal, and United States.

Cobweb spider

Habitat

Typically found in terrestrial habitats from forests to deserts.

Range

Found across Europe (4 countries) and North America (Canada, United States). Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

Brown Cobblestone Lichen

The Brown Cobblestone Lichen (Acarospora fuscata) is a species in the genus Acarospora. It is currently classified as Least Concern on the IUCN Red List. Native to Europe and North America, inhabiting ecosystems characteristic of the region.

Cobweb spider

Enoplognatha thoracica is a slender cobweb spider in the family Theridiidae, a widespread group of three-dimensional web-building spiders found across the temperate regions of Europe and North America. This small spider, typically measuring 3–5 millimeters in body length, constructs irregular, tangled cobwebs in low vegetation, hedgerows, meadow margins, and scrubby habitats where it captures small flying and crawling arthropods. The body is pale yellowish-brown to creamy white with darker markings on the abdomen, and the legs are long and slender relative to body size, adapted for navigating the three-dimensional structure of its web. Like other theridiids, Enoplognatha thoracica uses a gum-foot trap technique in which sticky vertical threads attached to the substrate at their lower ends snap insects upward when disturbed, immobilizing prey effectively. The species occupies a range spanning much of Europe eastward into temperate Asia and has established populations in parts of North America, likely through accidental human-mediated dispersal. Females produce egg sacs that are guarded within the web until hatching. The species is associated with disturbed and edge habitats and tolerates moderate agricultural landscapes. It is classified as Vulnerable by some assessments, reflecting localized population pressures from habitat loss and intensification of land use in parts of its range, though other evaluations consider it more broadly secure.