New Fish Species Has Barbed Genitals, Natural Tramp Stamps

The newly discovered llanos mosquitofish (Gambusia quadruncus) seems fairly unremarkable at first blush. However, the brown, minnow-like fish, described by researchers from North Carolina State University for the first time this month in the Journal of Fish Biology, has evolved some breeding traits that make it a little more memorable than its peers. Males have developed a breeding mechanism that humans have mercifully left by the genetic wayside — a series of four barbed hooks that surround their genitals and are used to latch onto females during breeding. It’s rough.

Now, we’re no pageant judges around here, but we are willing to say that, just empirically and objectively speaking, that this is one particularly unpleasant looking genital barb. That said, when they’re trying to break through the tissue that blocks their mates’ genital pores, male mosquitofish are probably less than concerned with winning any beauty contests.

Barbed genitalia aren’t as uncommon in the animal kingdom as we might like to think. A variety of insects, snakes, and lizards have evolved genital barbs that leave their members resembling terrifying alien weapons. While a barbed penis often increases the likelihood of successful fertilization, they are, as one can (but should probably not) imagine, no picnic for females of the species. Researchers have shown that the barbed penises of seed beetles improve the odds of a female getting pregnant, but damage her reproductive tract so badly that it shortens her life span.

Male llanos mosquitofish aren’t the only ones getting weird with it sexually, though. Females of the species have developed a small colored spot just over their anus that denotes what species they are and when they are ready to breed, demonstrating that tramp stamps — which fill much the same role in humans — are actually an evolutionary trait. Why anyone would ever want to demonstrate that they were prepared to have a four-barbed penis put inside of them is kind of beyond us, but that may just demonstrate that our inability to understand women stretches across species barriers. It certainly wouldn’t come as a surprise.

No word on whether the rough-playing fish have evolved any sort of safe word system, but we’ll stay with this story all night if we have to.

(via Eurekalert, images courtesy of NC State University)

Relevant to your interests

• Here are some museum quality penises
• Those barbed penises may also be shortening their bearers lifespans, FWIW
• Get your minds out of the gutter, people — these are just blind, river dwelling amphibians