Sex Itself is Deadly for These Poor Little Male Spiders

For these male spiders, having sex starts an irreversible process that ends with their death

A female dark fishing spider. Photo: Wikimedia Commons

Sex is a dangerous business. In the animal world, it’s not altogether uncommon for females to eat their mates post-coitus—I mean, she doesn’t need the male any more, and he’s like right there. One of the most famous examples of a lady eating her man is the famed black widow, but there’s another type of spider for which sex is even more treacherous. You see, if a male black widow is quick enough, or if the lady is stuffed from having eaten already, he can usually get away. For the male dark fishing spider, though, sex means death. Guaranteed.

“New research shows that the male Dolomedes tenebrosus expires just after the height of passion, despite no visible assault by his partner,” says Science reporting on a new study.

For the male dark fishing spider, they only get one shot at love, says Nadia Drake for Wired. Sex begins an irreversible process that only ends with them laying nearly lifeless, legs curled under their now-still corpse. Wired:

The reason is an unusual quirk of the male dark fishing spider’s physiology. During mating, a male inflates what’s called a hematodochal bulb inside the pedipalp, the appendage he uses to deposit sperm in the female. In most species, the bulb can be deflated after mating. In dark fishing spiders, it’s irreversibly inflated, resulting in a sudden shift in blood pressure that causes the male to curl up and leaves him immobilized and stuck to the female – doomed but not immediately dead.

“The act of sperm transfer is triggering this cascade of death,” said one of the study’s authors to Drake. “Once that button is pushed, it’s lights out.”

With the male spider just laying there dying, the female dark fishing spider figures hey, what the heck, and eats him alive. Gives another meaning to the French euphemism for orgasm “la petit morte,” or “the little death.”

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