Cobweb weaver vs Common Sun Beetle

Steatoda nobilis compared with Amara aenea

Key Differences

• Cobweb weaver is Not Evaluated while Common Sun Beetle is Least Concern.

Taxonomic Classification

Rank	Cobweb weaver	Common Sun Beetle
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Arthropoda (Arthropods)	Arthropoda (Arthropods)
Class	Arachnida (Arachnids)	Insecta (Insects)
Order	Araneae (Araneae)	Coleoptera (Beetles)
Family	Theridiidae	Carabidae
Genus	Steatoda	Amara
Species	Steatoda nobilis	Amara aenea

Evolutionary Relationship

Cobweb weaver and Common Sun Beetle share a common ancestor at the Phylum level: Arthropoda. (Arthropods)

Conservation Status

Cobweb weaver

NE — Not Evaluated

Common Sun Beetle

LC — Least Concern

Physical Characteristics

Attribute	Cobweb weaver	Common Sun Beetle
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Cobweb weaver

Habitat

Typically found in terrestrial habitats from forests to deserts.

Range

Widely distributed across Europe (7 countries), North America (United States), and South America (Ecuador).

Common Sun Beetle

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Found across Europe (7 countries) and North America (Canada, United States).

Cobweb weaver

The noble false widow (Steatoda nobilis) is a theridiid spider that has attracted considerable media attention in the British Isles and along the Atlantic coast of Europe due to its painful but rarely dangerous bite and its rapid range expansion facilitated by human activity. Originally native to the Canary Islands and Madeira, the species arrived in southern England during the 19th century, likely via banana shipments, and has since spread northward through Britain and westward into Ireland, while also establishing populations along the Iberian Peninsula and Atlantic France. Females are robust, with a dark brown carapace and a distinctive cream-colored pattern on the bulbous abdomen that varies between individuals; females reach 8.5–14 millimeters in body length, making this one of the larger European theridiids. The species constructs persistent, tangled cobwebs in sheltered locations outside buildings—under window ledges, in door frames, and in garden walls—as well as within homes in cooler seasons. It is a generalist predator, capturing insects and other invertebrates, and has been reported to occasionally subdue prey considerably larger than itself, including small lizards. Steatoda nobilis venom produces steatodism, which can cause localized pain, swelling, and in rare cases systemic symptoms. Its conservation status has not been formally assessed, but its expanding range demonstrates considerable resilience.

Common Sun Beetle

<em>Amara aenea</em>, the common sun beetle, is a carabid ground beetle in the family Carabidae, order Coleoptera. It is broadly distributed across Europe and has been introduced to North America, typically inhabiting open, sunny habitats such as arable fields, grasslands, sandy heathlands, and disturbed ground with sparse vegetation. Adults are omnivorous, feeding on seeds, small invertebrates, and plant material, and are considered important predators of weed seeds in agricultural systems. <em>Amara aenea</em> is surface-active during warm, dry conditions, typically exhibiting peak activity in late spring and summer. Like many carabid beetles, it is nocturnal and shelters under stones and debris during the day. Larvae develop in the soil, where they also feed on organic matter and small invertebrates. Biological traits including precise adult lifespan, body length measurements, and detailed prey preferences remain poorly documented at the species level. The species is assessed as Least Concern by the IUCN, reflecting its wide distribution, high adaptability to disturbed environments, and no significant known threats to global population status.

Shared Countries

Both species can be found in 4 countries:

🇧🇪 Belgium 🇩🇰 Denmark 🇵🇹 Portugal 🇺🇸 United States