cobweb spiders vs common bottlenose dolphin

Steatoda grossa compared with Tursiops truncatus

Taxonomic Classification

Rank	cobweb spiders	common bottlenose dolphin
Kingdom same	Animalia (動物)	Animalia (動物)
Phylum	Arthropoda (節足動物)	Chordata (脊索動物)
Class	Arachnida (クモガタ類)	Mammalia (哺乳類)
Order	Araneae (クモ目)	Cetacea (Whales & Dolphins)
Family	Theridiidae	Delphinidae (Oceanic Dolphins)
Genus	Steatoda	Tursiops (Bottlenose Dolphins)
Species	Steatoda grossa	Tursiops truncatus

Evolutionary Relationship

cobweb spiders and common bottlenose dolphin share a common ancestor at the Kingdom level: Animalia. (動物)

表示 Kingdom: Animalia

Conservation Status

cobweb spiders

LC — Least Concern

common bottlenose dolphin

LC — Least Concern

Population: ~600.0K

Trend: Stable →

Physical Characteristics

Attribute	cobweb spiders	common bottlenose dolphin
Diet	—	Carnivore
Average Lifespan	—	45 years
Average Length	—	3.0 m
Average Weight	—	300.0 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).

common bottlenose dolphin

Habitat

Found across multiple habitat types including tropical and subtropical moist broadleaf forests, tropical and subtropical dry broadleaf forests, and tropical and subtropical grasslands and savannas, among 12 distinct biome types. Populations are also found in montane and highland environments at higher elevations.

Range

Widely distributed across Asia (Taiwan), Europe (6 countries), and South America (Colombia, Ecuador, Venezuela).

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.

common bottlenose dolphin

最も研究され、最も知られているイルカ種であるバンドウイルカは、沿岸の浅瀬から外洋まで世界中の温暖な海域と温帯海域に生息します。体に対して大きな脳を持つ高度に知性的なこの種は、自己認識、複雑なコミュニケーション、社会的学習を示します。流動的な分裂融合社会で生活し、魚を追い込むために協力します。海洋生態系の健全性の重要な指標種です。