Coast Myall vs cobweb spiders

Acacia binervia compared with Steatoda grossa

Taxonomic Classification

Rank	Coast Myall	cobweb spiders
Kingdom	Plantae (Plants)	Animalia (Animals)
Phylum	Magnoliophyta (Flowering Plants)	Arthropoda (Arthropods)
Class	Magnoliopsida (Dicots)	Arachnida (Arachnids)
Order	Fabales (Legumes & Allies)	Araneae (Araneae)
Family	Fabaceae	Theridiidae
Genus	Acacia	Steatoda
Species	Acacia binervia	Steatoda grossa

Conservation Status

Coast Myall

LC — Least Concern

cobweb spiders

LC — Least Concern

Physical Characteristics

Attribute	Coast Myall	cobweb spiders
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Coast Myall

Habitat

Typically found in diverse terrestrial habitats from tropical forests to temperate regions.

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).

Coast Myall

Coast myall (Acacia binervia) is a small to medium tree or tall shrub in the family Fabaceae, native to coastal and near-coastal regions of New South Wales and Queensland in eastern Australia. It grows in coastal heath, dry sclerophyll woodland, and scrubby vegetation on sandy or rocky substrates, often in association with banksias and eucalypts. Like most Australian wattles, coast myall produces phyllodes—flattened leaf-stalks functioning as leaves—rather than true compound leaves in mature plants. The dark green phyllodes are distinctive, with two main veins, giving rise to the species name binervia. Golden-yellow, spherical flower heads are produced in winter to spring, attracting native bees. The genus Acacia sensu lato encompasses hundreds of species across Australia and globally, many of which play important ecological roles in nitrogen cycling through root symbioses. Coast myall is assessed as Least Concern by the IUCN. It is sometimes planted in coastal revegetation projects for its tolerance of poor, sandy soils, drought, and salt-laden winds.

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.