Arrow-Headed Flatworm in Zone 1

I’m still entering all of the data for species in Zone 1 for my Backyard Biodiversity Project. But there is an unexpected resident in this small Zone of stairs, cement and a narrow planter. Zone Map


This is an arrow-headed flatworm (Bipalium kewensis) a species of planarian. These are the kind of creatures that you may have experimented with in biology class dividing their bodies in a variety of ways to see that they can regenerate themselves if they have some part of a head.

The arrow-headed flatworm is an exotic species thought to be an Indo-Malayan import that came to the U.S. via Europe.

How did this creature come to be in my planter? How long have its ancestors frequented my neighborhood?

I found it under a brick in the planter. Interestingly, when I looked at the photos I realized that it appears to have some nasty gashes along its sides. And actually it seemed to be regenerating most of its head. How did it come to have these injuries? Did it encounter some kind of a predator? And what was that predator? Was it the resident of the cave?

It amazes me the stories you can discover when you look under a rock.