Episode 228 – Bedford’s Flatworm: Contentious Coupling

“…and today we’re talking about a flying magic carpet of the ocean. But more on that later.”

Motherhood is one of nature’s most lofty challenges, especially if you’re alone, in the wild, with limited resources. Protecting eggs or young, may mean giving up your own well-being, to give your offspring a fighting chance. But Bedford’s Flatworm has a plan to avoid this duty. Unfortunately, the strongest of the species is most able to escape responsibility on the darker side of Life, Death, and Taxonomy.

Description of Bedford’s Flatworm

  • Looks like an island that was made an hour ago by an active volcano
    • This is where Avatar Roku’s temple was 
  • It’s a flat floppy leaf-shaped thing with wavy edges
  • Its body is dark brown with orange curvy streaks going throughout it. 
  • It also has thousands of tiny yellow polka dots all over it

Measure Up

Welcome to the beloved Measure Up segment. The official listener’s favorite part of the show! The part of the show when we present the animal’s size and dimension in relatable terms through a quiz that’s fun for the whole family. It’s also the part of the show that’s introduced by you when you send in audio of yourself saying, singing, or chittering the words Measure Up into ldtaxonomy at gmail dot com. We don’t have a new Measure Up intro, but we’re going to revisit our greatest hits.

This week’s Measure Up greatest hit comes from Tom all the way back in June of 2019.


  • 8-10 centimeters (3.9 inches)
  • How many Bedford’s flatworms go into the diameter of the planet PSR B1620-26 b, also known as Methuselah.
  • Hint: Methuselah is a gas giant that orbits a white dwarf and a pulsar that orbit each other. The planet is very interesting, because it challenges the conventional wisdom of how planets are formed. Planets are thought to form from metal-rich stars, but methuselah formed in a metal-poor star system. Not only that, it’s a particularly massive planet.
  • 1,310,333,540 flatworms. Methuselah is 80,655 mi (129,801.64 km). It’s more massive than all of the planets in the solar system. 


  • 1 millimeter
  • How many flatworms go into the thickness of the thinnest smartphone in the world?
  • Hint: The thinnest phone as of this year is the Vivo X5 Max, which has made a name for itself purely for thinness. It’s not particularly technically impressive, but hey it’s thin.
  • 4.75 flatworms. The phone is 4.75 mm thick. 

Fast Facts about Bedford’s Flatworm

Range: All over the South Pacific including Indonesia, Australia, Thailand. Wikipedia says Keyna, but that’s insanely specific. Why not Somalia or Mozambique or even Madagascar?

Diet: Small crustaceans and ascidians, which are little stationary filter feeding organisms on the seafloor.


It can swim relatively quickly by undulating the edges of their bodies, kinda like stingrays. The  mainstream debut was the beginning of finding nemo. When they get stressed out, they can crack that cyanide tooth to off themselves. In reality, they actually dissolve in their own enzymes when they get stressed out

Major Fact: Contentious Coupling

Warning to parents: This Major Fact will include reproductive terminology. While not crass, it may involve some advanced vocabulary, if you catch my drift….

The magic carpet flatworm is a solitary man, and woman, since it’s hermaphroditic. They rarely encounter one another in the wild. Infact, they have the necessary tools to fertilize their own eggs and reproduce. But when they do meet each other, like Elden Ring dualists, there is an etiquette that must be performed. 

When two flatworms come together, they will engage in something called “penis fencing.”

Fangs for Thangs

The magic carpet flatworm has a two-pronged penis that protrudes from their ventral surface. To look at these cone-shaped appendages, you might assume it was more like fangs than anything else.

Any mating animal knows that it’s much easier to be a father than a mother, at least when it comes to gestating and carrying offspring. For a flatworm, looking after fertilized eggs is a labor intensive process. In other words, it’s better to give than to receive. 

The idea of reproducing without the extra responsibility and resource drain is enough to make even these introverted worms more gregarious. 

Body Shots

A literal stab with their fang-like inseminating weapon anywhere on the body will fertilize the other flatworm. But the other flatworm would also prefer to avoid the extra burden as well. So the duel commences.

The loser will take the L and the fertilized eggs. However, this process benefits everyone, because it ensures genetic diversity. It’s also a streamlined version of mating combat. Getting beaten means ensuring mixing in some physically fit genes into your eggs.

Ending: Go on a magic carpet ride, practice your parries and ripostes, and try not to get so stressed out that you dissolve in your own enzymes like the Bedford’s flatworm.