cobweb spiders vs Gray/Purple Heron

Steatoda grossa compared with Ardea cinerea

Taxonomic Classification

Rank	cobweb spiders	Gray/Purple Heron
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (Arthropods)	Chordata (Chordates)
Class	Arachnida (Arachnids)	Aves (Birds)
Order	Araneae (Araneae)	Pelecaniformes (Pelecaniformes)
Family	Theridiidae	Ardeidae
Genus	Steatoda	Ardea
Species	Steatoda grossa	Ardea cinerea

Evolutionary Relationship

cobweb spiders and Gray/Purple Heron share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

cobweb spiders

LC — Least Concern

Gray/Purple Heron

LC — Least Concern

Trend: Stable →

Physical Characteristics

Attribute	cobweb spiders	Gray/Purple Heron
Diet	—	Carnivore
Average Lifespan	—	15 years
Average Length	—	95 cm
Average Weight	—	1.5 kg

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).

Gray/Purple Heron

Habitat

Typically found in diverse ecosystems where prey species are available.

Range

Found across Europe (6 countries).

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.

Gray/Purple Heron

A large, elegant wading bird reaching up to 1 meter in height, gray herons inhabit wetlands, rivers, lakes, and coastal areas across Europe, Asia, and Africa. Patient, solitary hunters, they stand motionless for long periods before striking fish, frogs, and small mammals with lightning-fast dagger bill strikes. They nest colonially in tall trees in rookeries called heronries, sometimes shared with other colonial waterbirds. Widely distributed and of Least Concern globally.

Shared Countries

Both species can be found in 4 countries:

🇧🇪 Belgium 🇩🇰 Denmark 🇷🇺 Russia 🇸🇪 Sweden