Read More: ‘Chastity belts’ block rival sperm in female spiders https://www.newscientist.com/article/... “Some male spiders up-and-leave right after sex for good reason – they risk being eaten by their female partners if they linger too long. In the process of making a swift exit, many leave part of their genitalia inside their mates.”
Spider mating plugs become better with age http://www.nature.com/news/spider-mat... The males deposit a 'mating plug' inside the female to block out rival sperm and make sure that any offspring is theirs. Surprisingly, the effectiveness of these arachnid chastity belts depends not only on the plug’s size, but also on its age.
How Male Spiders Use Genital Plugs and Self-Castration to Ensure Paternity https://motherboard.vice.com/en_us/ar... Spiders are all about pushing the limits of sadomasochistic love-making. A few weeks back, Motherboard reported on the ins-and-outs of sexual cannibalism in wolf spiders. You'd think that would be enough kinky news from these arachnid weirdos for one year, but now it's time to talk about genital plugs.