curtain-web spider

curtain-web spider, (family Dipluridae), any member of a family of more than 150 species of mostly tropical spiders that are named for the messy funnel-shaped webs. These webs open wide at the mouth of the tube, and the nocturnal spider sits in the narrow funnel waiting for prey to contact the web. When this happens, the spider rushes out and captures the insect prey at the funnel’s mouth. Many species construct the web as the entrance to a burrow that makes use of an existing crevice or hollow, and some are cave-dwelling. Although the spiders are generally not aggressive, some can deliver a painful bite. The venom of most species is not considered medically significant to humans. The South American Trechona venosa has potent venom, but no human envenomation cases have been reported.

Physical description

Curtain-web spiders are mostly small- to medium-sized and are typically black, brown, or reddish in color. As spiders, they have a body formed of a fused head and thorax, known as a cephalothorax, and an abdomen. Their eight legs attach to the hard and often glossy cephalothorax and typically have sensory hairs that can pick up vibrations from approaching animals. The abdomen is tipped with four or six spinnerets, one pair of which is often notably long, that produce the silk used for web building.

Curtain-web spiders are mygalomorphs (infraorder Mygalomorphae) and thus have jaws that move forward and down (rather than sideways and together, which is characteristic of members of the infraorder Araneomorphae). They also have two other pairs of appendages near the mouth that aid in feeding: chelicerae and pedipalps. The more central chelicerae contain the venomous fangs, whereas the more lateral, leglike pedipalps are primarily used as feelers and to manipulate food. Pedipalps are also used by the males for reproduction. The arachnids also have two pairs of book lungs for respiration.

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Genera and taxonomy

There are eight genera of curtain-web spiders, the largest of which are Diplura, Linothele, and Masteria (the only Australian species in the family is M. toddae). The genera Harmonicon and Trechona have five and nine species, respectively. In 2024 a new genus of burrowing curtain-web spiders, Harpathele, was described in southeastern Brazil. Similarly, the genus Siremata contains three Brazilian species that were named in 2018, and Striamea, which also comprises three species, gained a new member in 2025.

The family has undergone a number of taxonomic revisions because of phylogenetic evidence. Perhaps the most notable revision is the placement of the venomous Australian funnel-web spiders (Atrax and Hadronyche) in their own family, Atracidae. Similarly, the former Dipluridae genera Brachythele, Microhexura, and Troglodiplura are now in other families, and the spiny curtain-web spiders were raised to family rank (Euagridae) in 2020.

Curtain-web spiders are unrelated to funnel weavers of the family Agelenidae.