Cobweb weaver vs Common Dwarf Bonneted Bat

Steatoda nobilis compared with Eumops bonariensis

Key Differences

• Cobweb weaver is Not Evaluated while Common Dwarf Bonneted Bat is Least Concern.

Taxonomic Classification

Rank	Cobweb weaver	Common Dwarf Bonneted Bat
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (artrópodos)	Chordata (cordados)
Class	Arachnida (arácnidos)	Mammalia (mamíferos)
Order	Araneae (araña)	Chiroptera (Bats)
Family	Theridiidae	Molossidae
Genus	Steatoda	Eumops
Species	Steatoda nobilis	Eumops bonariensis

Evolutionary Relationship

Cobweb weaver and Common Dwarf Bonneted Bat share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

Cobweb weaver

NE — Not Evaluated

Common Dwarf Bonneted Bat

LC — Least Concern

Physical Characteristics

Attribute	Cobweb weaver	Common Dwarf Bonneted Bat
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 Dwarf Bonneted Bat

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Range

Found in Venezuela.

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 Dwarf Bonneted Bat

<em>Eumops bonariensis</em>, the common dwarf bonneted bat, is a small molossid bat classified as Least Concern on the IUCN Red List, suggesting its populations are currently not under significant threat. The species has been recorded in Venezuela and is associated with diverse terrestrial and aquatic habitats, reflecting the broad ecological tolerance typical of many molossid bats. <em>Eumops bonariensis</em> belongs to the free-tailed bat family Molossidae and is characterized by its distinctive bonnet-shaped ears that extend over the forehead. Like other members of its genus, this species is adapted for fast, high-altitude flight and typically forages for flying insects in open airspace above forest canopies, wetlands, and urban areas. Molossid bats are known for their echolocation calls, which they use to detect and pursue prey during nocturnal foraging bouts. The species typically roosts in tree cavities, rock crevices, or man-made structures, forming small to moderate-sized colonies. Its insectivorous habits make it an important regulator of insect populations in tropical and subtropical ecosystems. Biological traits of this species remain poorly documented in the scientific literature.