How to Identify a Funnel Web Spider

Funnel web spiders are one of the most venomous spiders in Australia. The female spider produces a funnel-shaped web in damp places. It is quite important to identify funnel web spiders apart from their relatives. Generally, these spiders are black to dark brown in color. They are large compared to their relatives. They have shiny black, hairless cephalothorax. Long legs are one of the characteristic features of funnel web spiders.

Key Areas Covered

1. What is a Funnel Web Spider
– Definition, Fats, Classification
2. How to Identify a Funnel Web Spider
– Characteristic Features of Funnel Web Spiders

Key Terms: Abdomen, Body Size, Color, Funnel Web Spider, Legs, Venom

What are Funnel Web Spiders

Funnel web spiders are a type of spiders that build funnel-shape, silk-lined webs used as burrows or traps for prey. They are mainly found in both coastal and mountain regions of eastern and southern Australia. Generally, funnel web spiders are also called grass spiders as they prefer to live in grasslands. There are approximately 40 species of funnel web spiders. The two genera of funnel web spiders are Hadronyche and Atrax. Both genera produce dangerous venoms. However, Atrax is more venomous than Hadronyche, and 14 recorded deaths have been caused by them. In addition, the Sydney funnel spider (Atrax robustus) is the most dangerous spider in Australia. The funnel web on grass is shown in figure 1.

Figure 1: Funnel Web

How to Identify a Funnel Web Spider

The identification of funnel web spider is mainly based on the morphological features of the spider. Several features are involved in the identification of funnel web spiders from their relatives.

Fairly large body size
General body color is black
Black or dark plum-colored abdomen – Females have lighter colored abdomen when they carry lots of eggs.
Long, black color legs
Shiny black, hairless cephalothorax
Females construct funnel webs on damp soil, grass or tree trunks

The characteristics of male and female funnel web spiders are described below.

Male and Female Funnel Web Spiders

Figure 2: Male and Female Spiders

Characteristics	Male Spider	Female Spider
Body length	25 mm	30 mm
Color	Black to very dark brown	Very dark brown
Behavior	Leave the burrow, wandering in search of food	Stay in the barrow, grabbing any passing prey
Legs	Longer legs, more slender, and quite bristly	Shorter legs, less slender, and less bristly
Abdomen	Smaller abdomen, long slender spinnerets on the rear of the abdomen.	Bigger abdomen
Spur on second front leg	Present	Absent
Behavior	More robust	Less robust
Venomous nature	One of the most venomous spiders	Extremely venomous

Conclusion

Funnel web spiders are one of the most venomous spiders in Australia who produce a funnel-shaped web on grass. They are fairly large spiders with long legs. They are black to dark brown in color. They also have a shiny black, hairless cephalothorax.

Reference:

1. Funnel-Web Spiders – Australian Museum, Available here.
2. “Sydney Funnel Web Spider Facts.” Planet Deadly, 9 Dec. 2013, Available here.

Image Courtesy:

1.”Atrax Robustus” By Sputniktilt – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Spider Web in the Grass” by Tony Atkin (CC BY-SA 2.0) via Geograph.uk