cobweb spiders vs Collembola

Steatoda grossa compared with Folsomides angularis

Key Differences

• cobweb spiders is Least Concern while Collembola is Not Evaluated.

Taxonomic Classification

Rank	cobweb spiders	Collembola
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Arthropoda (Arthropods)	Arthropoda (Arthropods)
Class	Arachnida (Arachnids)	Collembola (springtail)
Order	Araneae (Araneae)	Entomobryomorpha (Entomobryomorpha)
Family	Theridiidae	Isotomidae
Genus	Steatoda	Folsomides
Species	Steatoda grossa	Folsomides angularis

Evolutionary Relationship

cobweb spiders and Collembola share a common ancestor at the Phylum level: Arthropoda. (Arthropods)

Conservation Status

cobweb spiders

LC — Least Concern

Collembola

NE — Not Evaluated

Physical Characteristics

Attribute	cobweb spiders	Collembola
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

cobweb spiders

Habitat

Typically found in terrestrial habitats from forests to deserts.

Range

Widely distributed across Africa (South Africa), Europe (29 countries), North America (Canada, United States), and South America (Ecuador).

Collembola

Habitat

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

Range

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

cobweb spiders

The false black widow (Steatoda grossa) is a cosmopolitan cobweb spider in the family Theridiidae, often mistaken for the true black widow due to its similarly dark, globose abdomen, though it lacks the red hourglass marking. Females reach 6–10 millimeters in body length and display a deep purplish-brown to nearly black coloration with faint pale markings on the dorsal abdomen. Originally native to western Europe, Steatoda grossa has spread globally through human commerce, establishing populations in Australia, New Zealand, North America, and other regions where it thrives in human structures including homes, sheds, and outbuildings. The spider constructs a persistent, tangled cobweb in sheltered corners and recesses, where it captures woodlice, ants, beetles, and other arthropods—notably targeting invertebrates that many other spiders avoid. The venom of S. grossa causes steatodism, a syndrome of localized pain, sweating, and systemic discomfort that is rarely serious but can cause significant distress. Interestingly, the antivenin produced for Latrodectus (true widow) spider bites has been shown to effectively treat Steatoda envenomations, underscoring the phylogenetic relatedness of these genera. Females produce several egg sacs during a season, each containing dozens of eggs wrapped in distinctive silken cocoons. The species is classified as Least Concern given its expanding global distribution facilitated by human activity.

Collembola

<em>Folsomides angularis</em>, commonly referred to as Collembola in reference to its broader taxonomic order, is a springtail species belonging to the genus <em>Folsomides</em>. Springtails are among the most abundant hexapods in terrestrial ecosystems, playing important roles in soil decomposition and nutrient cycling. This species has been documented in Europe, with records from Denmark, Norway, and Sweden, as well as North America, where it is known from the United States. It typically inhabits soil, leaf litter, and decaying organic matter, and is capable of tolerating a range of environmental conditions. Springtails of this group are detritivores, feeding on decomposing plant material, fungal hyphae, and microorganisms, though specific dietary data for <em>Folsomides angularis</em> are not detailed in current records. The species has not been formally assessed for conservation status. Biological traits of this species remain poorly documented in the scientific literature. Its small body size and cryptic lifestyle make detailed ecological study challenging.

Shared Countries

Both species can be found in 3 countries:

🇩🇰 Denmark 🇸🇪 Sweden 🇺🇸 United States