cobweb spiders vs Coimbra-Filho’s Titi

Steatoda grossa compared with Callicebus coimbrai

Key Differences

• cobweb spiders is Least Concern while Coimbra-Filho’s Titi is Endangered.

Taxonomic Classification

Rank	cobweb spiders	Coimbra-Filho’s Titi
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (Arthropods)	Chordata (Chordates)
Class	Arachnida (Arachnids)	Mammalia (Mammals)
Order	Araneae (Araneae)	Primates (Primates)
Family	Theridiidae	Pitheciidae
Genus	Steatoda	Callicebus
Species	Steatoda grossa	Callicebus coimbrai

Evolutionary Relationship

cobweb spiders and Coimbra-Filho’s Titi share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

cobweb spiders

LC — Least Concern

Coimbra-Filho’s Titi

EN — Endangered

Physical Characteristics

Attribute	cobweb spiders	Coimbra-Filho’s Titi
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

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).

Coimbra-Filho’s Titi

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

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.

Coimbra-Filho’s Titi

The Coimbra-Filho's Titi (Callicebus coimbrai), also known as Coimbra-Filho's Titi Monkey, is a small New World monkey in the family Pitheciidae, named in honour of the Brazilian primatologist Adelmar F. Coimbra-Filho. This titi monkey is endemic to the Atlantic Forest of northeastern Brazil, with its range restricted to the states of Sergipe and southern Alagoas—one of the most critically fragmented and threatened biomes on Earth. Adults are small, with reddish-brown fur on the flanks and upperparts, pale grey on the underparts, and an orange-red forehead band. Like all titi monkeys, Callicebus coimbrai is highly social, living in monogamous family groups of 2–5 individuals that engage in elaborate dawn duets and tail-twining behaviour as expressions of pair bonding. The species inhabits Atlantic Forest fragments, including lowland and highland forest patches, riverine gallery forest, and secondary growth, where it subsists on fruits, seeds, leaves, and occasional invertebrates. The Coimbra-Filho's Titi is classified as Endangered by the IUCN due to its severely fragmented range within one of the world's most deforested biomes, with less than 12% of original Atlantic Forest remaining, ongoing habitat loss from agricultural expansion, and small, isolated population sizes highly vulnerable to stochastic extinction events.