In an excellent new discovery in Brazil, insects of the Neotrogla genus who live in caves have been discovered with completely role-reversed genitalia. The boss female has a penis and the male has a vagina, and they get after it for 40-70 hour stretches.

According to a study in Current Biology, this isn't the first female creature with a penis, but it is the only example where the "intromittent organ is also reversed."

Neotrogla females insert the erectile organs into males' vagina-like openings.

The elaborate structure, dubbed a "gynosome," is used to suck out sperm and nutritious seminal fluids.

There's a little insect erotica for you on Easter Sunday.

The rigorous copulation also provides the female insects with food as well as sperm, so having a lot of sex is advantageous for the insects. And don't try to stop them, either:

When the researchers attempted to pull a male and female apart, the male's abdomen was ripped from the thorax without breaking the genital coupling.

Brazilian cave insects, an inspiration to us all in the boudoir.

[Image via BBC]