Caucasian Alder vs Cobweb spider

Alnus subcordata compared with Enoplognatha thoracica

Key Differences

• Caucasian Alder is Least Concern while Cobweb spider is Vulnerable.

Taxonomic Classification

Rank	Caucasian Alder	Cobweb spider
Kingdom	Plantae (Plants)	Animalia (Animals)
Phylum	Magnoliophyta (Flowering Plants)	Arthropoda (Arthropods)
Class	Magnoliopsida (Dicots)	Arachnida (Arachnids)
Order	Fagales (Beeches & Oaks)	Araneae (Araneae)
Family	Betulaceae	Theridiidae
Genus	Alnus	Enoplognatha
Species	Alnus subcordata	Enoplognatha thoracica

Conservation Status

Caucasian Alder

LC — Least Concern

Cobweb spider

VU — Vulnerable

Physical Characteristics

Attribute	Caucasian Alder	Cobweb spider
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Caucasian Alder

Habitat

Typically found in diverse terrestrial habitats from tropical forests to temperate regions.

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.

Caucasian Alder

The Caucasian Alder (Alnus subcordata) is a species in the genus Alnus. It is currently classified as Least Concern on the IUCN Red List. Typically found in diverse terrestrial habitats from tropical forests to temperate regions.

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.