paramere

A paramere is an appendage that occurs on the pedipalp, or peduncle, of male spiders. It is a claw-like structure that is often used during mating. The paramere can be an important characteristic in identifying species, as it can vary significantly between different spider families.

In some species of spiders, the paramere is said to be 'fixed' or 'non-movable', where it is not capable of being moved by the male. This is distinct from species where the paramere can be moved about by the male. The paramere may also be subject to modifications in different regions, with the paramere being different from the pedipalp or peduncle.

The name of the structure comes from Greek roots. Where the 'para' is located 'before' or 'adjacent to something else' and'mere' means'member or part'. This gives the name 'paramere' its true mechanical and biological indication.

The function of the paramere may vary depending on the species. It may be used as part of the male's courtship display, or used to hold onto the female. In some species, the paramere is involved directly in the transfer of sperm to fertilize the egg or eggs. In other cases, it is involved in a distinctive copulatory courtship behavior that involves contact between the male and female.

In spiders using sperm webs to fertilize eggs, the paramere is not involved in the process. The deposition of spermatophores onto the web is typically without this 'apparatus'. However, species of spiders using this sperm web system are markedly different from species in which the paramere functions in the mating process.