By Stephanie Pappas, Live Science Contributor | March 3, 2017 06:55am ET
A new worm discovered on the Iberian Peninsula is missing something: a penis.
The tiny nematode, found in a compost pile, mates without penetration. Instead, it pumps a capsule full of sperm out of an opening in its body and into a funnel-like structure on the female's vulva. From there, the sperm enter the female's reproductive tract to fertilize her eggs.
"We are sampling [the whole] Iberian Peninsula from several decades ago, and we never found a similar species, and, [with] respect to other countries, it is very rare that other researchers find some species of this genus," Joaquín Abolafia, a biologist at the University of Jaén and the discoverer of the new species, wrote in an email to Live Science. "For that reason, this discovery is surprising."
The worm is unlike other nematodes in ways other than its weird genitals. (More commonly, nematode males have penis-like organs called spiculesthat the animals use to penetrate females.) This newfound worm also has two layers of skin, or cuticle, one of which comes from the worm's juvenile moult. Instead of fully shedding the skin, the creature keeps the layer attached. This second skin protects the worm from drying out in the arid summers of the Iberian Peninsula, the researchers reported in December in the journal Zootaxa.