cobweb spiders vs Colombian Small-eared Shrew

Steatoda grossa compared with Cryptotis colombiana

Taxonomic Classification

Rank	cobweb spiders	Colombian Small-eared Shrew
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (Arthropods)	Chordata (Chordates)
Class	Arachnida (Arachnids)	Mammalia (Mammals)
Order	Araneae (Araneae)	Soricomorpha (Soricomorpha)
Family	Theridiidae	Soricidae
Genus	Steatoda	Cryptotis
Species	Steatoda grossa	Cryptotis colombiana

Evolutionary Relationship

cobweb spiders and Colombian Small-eared Shrew share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

cobweb spiders

LC — Least Concern

Colombian Small-eared Shrew

LC — Least Concern

Physical Characteristics

Attribute	cobweb spiders	Colombian Small-eared Shrew
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).

Colombian Small-eared Shrew

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Range

Found in Colombia.

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.

Colombian Small-eared Shrew

<em>Cryptotis colombiana</em>, the Colombian small-eared shrew, is a diminutive insectivorous mammal belonging to the family Soricidae, endemic to Colombia. This species typically inhabits montane environments, including humid cloud forests and high-altitude grasslands known locally as páramo, where it forages actively through leaf litter and soil for invertebrate prey. Small-eared shrews of the genus <em>Cryptotis</em> are characterised by their notably reduced external ears, high metabolic rates, and nearly constant activity cycles driven by the energetic demands of maintaining body temperature. <em>Cryptotis colombiana</em> is currently assessed as Least Concern by the IUCN, suggesting that its population is relatively stable within its Colombian range. Despite this status, Andean shrews face ongoing pressures from land conversion, cattle grazing in páramo ecosystems, and climate-driven shifts in vegetation zones. The species contributes to soil aeration and invertebrate population regulation within its montane habitat. Biological traits of this species remain poorly documented in the scientific literature.