Do Spiders Have Penises?

Spiders are tiny and have complex behavioral requirements. These include the need for sensitivity, ability to detect light and dark, and the presence of modified legs. Some of these creatures have well-developed vision, while others have only limited capabilities.

Male spiders possess a pair of pedipalps, or modified legs, that transfer sperm. This process is similar to that of scorpions. When a male approaches a female, the palps are activated and a sperm packet is deposited on a small web. The syringe-like structures on the palps are designed to catch falling sperm.

Female spiders have a sclerotized, external genital structure known as an epigyne. In addition, she has a spermatheca, which is a storage organ that holds sperm. They also have stretch receptors that allow the female to detect the fitness of the male.

Female spiders are able to choose which sperm to fertilize her eggs. She can eject sperm if the male is not suitable. Her sperm can be stored in seminal receptacles after copulation.

Male spiders have a penis, or reproductive apparatus, that is adapted to deliver sperm. It ends in a needle-sharp tip called an embolus. The genitals can be as large as three or four times the length of the spider. A large pedipalp is needed to penetrate a female’s sex hole.

Female spiders often eat their males after mating. Some species, like the Australian redback spider, have a habit of consuming a male in the process of reproduction.