Scientists just found a 50-million-year-old fossilized bug penis. That's huge. And also very small.

A new paper published in the Journal of Paleontology, titled "A new remarkably preserved fossil assassin bug (Insecta, Heteroptera, Reduviidae) from the Eocene Green River Formation of Colorado" contains a lil' surprise below the bug belt. As Haaretz reports:

Looking at the photograph, one's eyes are drawn to the dark figure-8 seemingly attached to the insect's middle leg – but that's not the lad's gonads, it's a beetle. The genitals of the insect, sprawled forever more with his six legs akimbo, are at the end of the last body segment. What we see is the sac called the pygophore (aka pygofer), which derives from the Greek word pyg for "rump" and phore for "bearer."

Ironically, if anything, according to this picture this genital capsule looks like a vulva. But it is not.

Think of the pygophore as a sort of chitinous codpiece. "It is a cup, hardened like the rest of the exoskeleton, that contains all of the typically softer, internal parts of the insect's genitalia," Swanson explains to Haaretz.  

Asked if lady assassin bugs have pygophores too, he relates that in "true bugs" (suborder Heteroptera), they do not. Only the male. Also, close inspection clearly shows the boy bug's basal plate: a stirrup-shaped structure that supports the insect's penis, the researchers say.

Only about 50 or so species of assassin bugs have been discovered in fossil form, according to The New York Times. Which makes this once-squishy genital discovery that much more remarkable.

'A Rare Treat': Paleontologists Detect 50-million-year-old Fossil Bug Penis [Ruth Schuster / Haaretz]

A Surprise in a 50 Million-Year-Old Assassin Bug Fossil: Its Genitals [Katherine J. Wu / The New York Times]

Image: Public Domain via NeedPix