Southern Sydney Funnel-web Spider, Atrax montanus

Previously considered part of the variation within the Sydney Funnel-web, this species may be just as venomous as its sister-species Atrax robustus.

Identification

Southern Sydney Funnel-webs are shiny, dark brown to black spiders with finger-like spinnerets (silk-spinning organs) at the end of their abdomen. Males have a large mating spur projecting from the middle of their second pair of legs. This species cannot easily be separated from the Sydney Funnel-web by eye. If threatened, both species show aggressive behaviour, rearing and displaying their impressive fangs.

Habitat

Bushy suburban areas and forests. Southern Sydney Funnel-webs may require more moisture and shading than the Sydney Funnel-web. They are often found under rocks or tree logs in or near rainforest gullies.

Distribution

The Southern Sydney Funnel-web Spider (Atrax montanus) occurs in New South Wales, from the Watagans south to Bowral and west to the upper Blue Mountains. The species overlaps with A. robustus in distribution, however, its range is mainly to the south and west of Sydney. Historically, this species occurred in some forested gullies in the eastern suburbs, together with the Sydney Funnelweb. However, there are no records of either species from these areas since the 1970s.

Feeding and diet

Southern Sydney Funnel-webs live in silk-lined burrows in sheltered sites under logs and rocks in moist gullies where they can maintain a cool and humid climate. When hungry, the spider waits inside the burrow entance ready to rush out when potential prey, such as beetles, cockroaches, small lizards or millipedes, walk across silken trip-lines that the spider has placed around the outside of its burrow. They then return to their burrow to eat their meal.

Other behaviours and adaptations

Male Funnel-web spiders have a habit of wandering into backyards and falling into suburban swimming pools, where they can survive many hours. They also sometimes enter and become trapped in houses. Dry daytime surface conditions will dehydrate funnel-web spiders and also expose them to birds and lizards. This is why males that have spent the humid night in search of a female have to seek cover at dawn. This can be any suitable hideaway that is dark, moist and cool, like a cavity under a rock, or even in a shoe left outdoors.

A number of other spiders are often mistaken as funnel-webs, including mouse spiders, trapdoor spiders and even Black House Spiders. Always seek urgent first aid if a bite might have been inflicted by a funnel-web.

Breeding behaviours

Males leave their burrows and wander, mostly over summer and autumn to find females and mate.

Danger to humans

Funnel-web bites are dangerous and first aid should be given immediately using the pressure bandage/immobilisation technique (as for snake bite) and the victim taken to hospital and given antivenom if necessary. The venom has a neurotoxin component that attacks the human nervous system and, in the worst cases, can result in death. However, there have been no fatalities since the introduction of antivenom.

References

• Isbister, G, Gray, M, Balit, C, Raven, R, Stokes, B, Porges, K, Tankel, A, Turner, E, White, J, and Fisher, M. 2005. Funnel-web spider bite: a systematic review of recorded clinical cases. Medical Journal of Australia 182(8): 407-411.
• Gray, M. 2010. A revision of the Australian funnel-web spiders (Hexathelidae: Atracinae). Records of the Australian Museum 62: 285-392.
• Loria, S.F., Frank, SC., Dupérré, N. et al. The world’s most venomous spider is a species complex: systematics of the Sydney funnel-web spider (Atracidae: Atrax robustus). BMC Ecol Evo 25, 7 (2025). https://doi.org/10.1186/s12862-024-02332-0
• Crossman S, Li O. Surface Hydrology Polygons (National). Geoscience Australia, Canberra. 2015. https://pid.geoscience.gov.au/dataset/ga/83135