Deinopidae spiders are a small family of net-casting spiders best known for their unusual hunting method and oversized eyes. Instead of building a typical web to wait for prey, they hold a small silk net between their front legs and throw it over passing insects at night. That makes them one of the most distinctive spider groups people may encounter in tropical and subtropical areas.
Quick answer
Deinopidae spiders are net-casting spiders, often called ogre-faced spiders in the genus Deinopis. They have long, stick-like bodies, very large eyes, and hunt at night by dropping a stretchy silk net over insects. They are not considered dangerous to people.
Overview
Deinopidae is a family of cribellate spiders known for a hunting strategy that is very different from the usual orb web or funnel web approach. These spiders make a small rectangular capture web, hold it between their front legs, and cast it over prey when the moment is right.
This family includes the well-known ogre-faced spiders (Deinopis) and the less familiar humped-back spiders (Menneus). While the exact appearance varies by species, Deinopidae spiders are generally easy to recognize once you know what to look for: a thin, elongated body, long legs, and a striking pair of large eyes adapted for night hunting.
Identification
Deinopidae spiders usually have a slim, stick-like body that helps them blend in with twigs and stems. Their legs are long and slender, and many hang upside down when resting or hunting.
One of their most noticeable features is their eye arrangement. In many species, especially Deinopis, the large rear-facing median eyes dominate the face and can make the spider look as if it has only two eyes. These oversized eyes are an important clue for identification.
Color varies by species, but common tones include brown, gray-brown, fawn, pinkish brown, or muted greenish-brown. Males are often smaller and more slender than females.
If you are trying to identify one in the field, look for these signs:
- a long, narrow body
- very large prominent eyes
- an upside-down resting posture
- a spider holding a small silk net between its front legs at night
Habitat
Deinopidae spiders are found mostly in tropical and subtropical regions, including parts of Australia, Africa, and the Americas. They are usually associated with vegetation rather than open ground.
They often rest among shrubs, low branches, fronds, and forest or garden plants. In some areas, species of Deinopis are known to spend the day hanging beneath leaves or palmetto fronds, then become active after dark.
Because they rely on camouflage and nighttime hunting, they are easy to miss during the day.
Behavior
Behavior is where Deinopidae spiders really stand out. They do not rely on a large stationary web to catch prey. Instead, they create a small woolly net from cribellate silk and hold it stretched between their front legs.
When hunting, the spider hangs from vegetation with its body pointed downward. The hind legs and silk lines help anchor it in place while it waits for an insect to pass below. Once prey moves into range, the spider lunges and throws the net downward, wrapping the insect in a fraction of a second.
Their eyesight is especially well suited to low light. The enlarged eyes help them detect prey at night, which is why many species are most active after sunset.
At rest, their body shape and posture help them resemble a small stick or dry twig. This camouflage likely helps protect them from predators during the day.
Diet
Deinopidae spiders feed on other invertebrates. Their prey can include:
- ants
- beetles
- crickets
- small wandering insects
- sometimes other spiders
After capturing prey with the net, the spider wraps it in silk, bites it to subdue it, and then feeds.
Are they dangerous?
Deinopidae spiders are venomous, like nearly all spiders that hunt live prey, but they are not considered dangerous to humans. Their venom is used to immobilize small insects, not to cause serious harm to people.
Bites are uncommon because these spiders are shy, nocturnal, and not aggressive. Most people are far more likely to overlook one than to be bitten by one.
If one is found in a garden or around vegetation, there is usually no reason for concern.
Life cycle
Females produce egg sacs that are typically suspended in low vegetation by silk. The sacs may be camouflaged with bits of debris, which helps them blend into their surroundings.
In some regions, adults are most often noticed during the warmer months, when mating and egg-laying take place.
Why they matter
Deinopidae spiders are valuable predators of small insects and are a good example of how specialized spider behavior can be. Their unusual net-casting method, strong night vision, and camouflage make them one of the most interesting spider families for naturalists and gardeners alike.
- Quick facts box
Quick Facts: Deinopidae Spiders
| Fact | Details |
|---|---|
| Common names | Net-casting spiders, ogre-faced spiders |
| Family | Deinopidae |
| Known for | Throwing a silk net over prey |
| Body shape | Long, slender, stick-like |
| Eye feature | Very large eyes, especially in Deinopis |
| Active time | Mostly nocturnal |
| Habitat | Vegetation in tropical and subtropical regions |
| Diet | Insects and other small invertebrates |
| Danger to humans | Not considered dangerous |
| Best identification clue | Large eyes + upside-down posture + handheld net |
