A Tasman Peninsula Dusky Antechinus (Photo: University of Queensland)

The antechinus, the tiny Australian marsupial that looks like a cute-enough cross of a rat and a mole (if moles could hop), has a very strange sex life. In the summer, these creatures spend about two or three weeks “speed-mating”—a frenzy of copulation that leaves the males, as one scientist puts it, ”physically disintegrating.”  The stress hormones they work up trying to have as much sex as possible end up destroying the males’ immune systems, and they die, leaving the local supply of delicious insects to their offspring.

The antechinus was first discovered in 1803, and for many years there were though to be only two species. But scientists at the University of Queensland have been pushing to discover “cryptic taxa” among the antechini, and they’ve now identified two additional species—Tasman Peninsula Dusky Antechinus and the Mainland Dusky Antechinus—bringing their total of antechinus species discovered up to five.

Like many species newly described by science, these are relatively rare and at risk of disappearing altogether. These live on mountains in southeast Queensland, in “perhaps the smallest distributions of any Australian mammal.” Their sex frenzy, in this context, isn’t necessarily an advantage: it means that the species’ survival depends entirely on the next generation—every year, the antechinus females need to produce enough males for the deadly orgy to come.

Bonus finds: 12,000-year-old arrowheads, a Byzantine shipwreck13th century gambling pieces

Every day, we highlight one newly lost or found object, curiosity or wonder. Discover something unusual or amazing? Tell us about it! Send your finds to sarah.laskow@atlasobscura.com.