cobweb spiders vs Commerson's Leaf-nosed Bat

Steatoda grossa compared with Macronycteris commersonii

Key Differences

• cobweb spiders is Least Concern while Commerson's Leaf-nosed Bat is Near Threatened.

Taxonomic Classification

Rank	cobweb spiders	Commerson's Leaf-nosed Bat
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum	Arthropoda (Arthropods)	Chordata (Chordates)
Class	Arachnida (Arachnids)	Mammalia (Mammals)
Order	Araneae (Araneae)	Chiroptera (Bats)
Family	Theridiidae	Hipposideridae
Genus	Steatoda	Macronycteris
Species	Steatoda grossa	Macronycteris commersonii

Evolutionary Relationship

cobweb spiders and Commerson's Leaf-nosed Bat share a common ancestor at the Kingdom level: Animalia. (Animals)

Conservation Status

cobweb spiders

LC — Least Concern

Commerson's Leaf-nosed Bat

NT — Near Threatened

Physical Characteristics

Attribute	cobweb spiders	Commerson's Leaf-nosed Bat
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).

Commerson's Leaf-nosed Bat

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.

Commerson's Leaf-nosed Bat

<em>Macronycteris commersonii</em>, commonly known as Commerson's Leaf-nosed Bat, is a chiropteran mammal in the family Hipposideridae. This species is assessed as Near Threatened on the IUCN Red List, indicating that it faces increasing pressures that could elevate its risk of extinction without conservation attention. Commerson's Leaf-nosed Bat typically inhabits a range of diverse ecosystems across sub-Saharan Africa, including forests, savannas, and areas near caves or rocky outcrops that serve as roosting sites. Like other hipposiderid bats, it uses echolocation to navigate and hunt in low-light conditions, often foraging for insects in open or semi-open environments after dark. Roost disturbance, habitat degradation, and human persecution are among the primary threats facing this species. The large, elaborately shaped noseleaf characteristic of the family helps focus echolocation signals during foraging. Populations are typically found roosting in caves, mines, and hollow trees in groups that may range from small colonies to large aggregations. Biological traits of this species remain poorly documented in the scientific literature.