cobweb spiders vs koala

Steatoda grossa compared with Phascolarctos cinereus

Key Differences

• cobweb spiders is Least Concern while koala is Vulnerable.

Taxonomic Classification

Rank	cobweb spiders	koala
Kingdom same	Animalia (สัตว์)	Animalia (สัตว์)
Phylum	Arthropoda (สัตว์ขาปล้อง)	Chordata (สัตว์มีแกนสันหลัง)
Class	Arachnida (แมง)	Mammalia (สัตว์เลี้ยงลูกด้วยน้ำนม)
Order	Araneae (แมงมุม)	Diprotodontia (Marsupials)
Family	Theridiidae	Phascolarctidae (Koalas)
Genus	Steatoda	Phascolarctos (Koalas)
Species	Steatoda grossa	Phascolarctos cinereus

Evolutionary Relationship

cobweb spiders and koala share a common ancestor at the Kingdom level: Animalia. (สัตว์)

Conservation Status

cobweb spiders

LC — Least Concern

koala

VU — Vulnerable

Population: ~100.0K

Trend: Decreasing ↓

Physical Characteristics

Attribute	cobweb spiders	koala
Diet	—	Herbivore
Average Lifespan	—	15 years
Average Length	—	75 cm
Average Weight	—	10.0 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).

koala

Habitat

Typically found in grasslands, forests, and vegetated habitats.

Range

Found in Australia. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

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.

koala

Iconic marsupial of eastern and southeastern Australia, koalas weigh up to 15 kg and spend up to 22 hours daily sleeping to conserve energy from their low-calorie eucalyptus leaf diet. Highly specialized to process toxic eucalyptus compounds that would kill most other mammals, they have gut microbiomes uniquely adapted for detoxification. Listed as Endangered in 2022, with populations decimated by chlamydia disease, habitat clearing, and climate change.