- What the plural of 'penis'? Penises? Peni? Penisies?
Thousands of pink wiggly worms were found at Pajaro Dunes, Moss Landing, Bodega Bay, and Princeton Harbor in California after was meteorologists call a bomb cyclone. What are they? Well, one name is Penis Fish.
First, Let’s Address The Name
Urechis Caupo, or the ‘penis fish’, is a type of spoonworm, an order of non-segmented marine worms. They are collectively called, Urechidea. There are four species of the Urechidea worms. The one that has appeared in Southern Oregon to Baja, is the Innkeeper. This type is usually found in California. They can be identified by a spatula-shaped proboscis used for feeding and sometimes grasping and swimming.
Why Are They Shaped The Way They Are?
The fat innkeeper is shaped to be underground. It digs a U-shaped burrow extending a few inches below the ground, but no wider the worm itself. The front entrance pokes up like a chimney. They can be seen clustered around the low tide line of mudflat or sandy beaches. The backdoor is marked by a pile of worm castings. These get projected out of the end of the tunnel with a blast of water from the worm’s rear end.
“It’s Not Slime! It’s Mucous!” (Or) How They Escape
When the tide comes, the worm slides up the chimney of its burrow and exudes a sticky mucous net from a ring of glands. The nets look like decaying jellyfish and are draped across the entrance of the burrow. Innkeepers generate the mucous as it slips lower in the burrow. Using contractions to pump water through its burrow, the worm can suck plankton and bacteria into its net. When the net gets clogged, the worm slurps it all back into its mouth, taking the particles it wants to eat and discarding the rest into the tunnel.
‘Leftovers’ Anyone?
The ‘leftovers’ are taken by a cast of freeloaders who live in the burrow. These freeloaders include: Clams (Cryptomya California, a ‘sequined’ scale worm (Hesperonoe adventure), a pea crab (Scleroplax granulate or Pinnixa Franciscan), a hooded shrimp (Betaeus longidactylus), and a fish, the arrow goby (Clevelandia ios). Where the shrimp and fish come and go, the first three are more permanent residents. Finally, when the food runs out they mooch off of other industrious invertebrates. The goby will sometimes bring food to the crab, which minces it into smaller pieces, which allows the goby to take and eat it. This gives the ‘Fat Innkeeper’ its name.
The ‘Innkeeper’ Is Cool With It?
Actually, the ‘Innkeeper’ has almost no issue with it at all! In fact, this is a perfect example of commensalism – a relationship in which one organism forms a dependency of another, the latter being neither hurt nor helped in the relationship. The ‘Innkeeper’ has fossils of evidence that the U-shaped burrows date back 300 million years ago! They have a recorded life up to 25-years-old. Otters, flounders, sharks, rays, seagulls, and humans (Yes, people in South Korea eat these worms.) prey on these worms.