In the middle of the 19th century,
a scientist stared into his microscope and found, staring back at him, a vampire.
Like the creatures of legend, the organism he saw was a shape-shifter,
though not the kind whose body contorts from something vaguely human
into something more like a bat.
No, what he found was an amoeba.
And it was in search of something to sink its fangs into.
The amoebas we’re discussing today belong to the order Vampyrellida, which holds two families.
The first is the family Vampyrellidae, made up of organisms known generally as vampyrella.
And the second Family is Leptophryidae, which holds essentially everything else.
The Leptophrys we’re looking at now, the Arachnula we opened the episode with,
and a bunch others.
Now we’re not here today to navigate the complicated taxonomic histories here though.
We want to state upfront that while we’re going to be using
the name “vampyrellids” as a convenient label,
the organisms who are gathered under that umbrella have a wider array of identities.
“Vampyrella” translates to “little vampire” in Latin.
The name was first given to members of the Vampyrellida order in 1865
by the Polish microbiologist Leon Cienkowski,
who was very much inspired by the vampires of lore when naming these creatures.
When you think of vampires, perhaps you think of blood and viciousness.
But the vampyrellid does not want blood.
It wants is cytoplasm.
And yes, it will be vicious to get what it wants.
We know of about 50 species of vampyrellids, scattered all around the world.
Some, like ours, live in ponds, living among filamentous algae and desmids.
Others prefer marine environments, while some can be found in soil.
But despite this range of environments,
they share a very distinct life cycle that revolves around feeding.
The first stage of life is the trophozoite,
though in the past it’s also been known as the swarmer stage.
That’s because this is the time of the vampyrellid’s life when it is on the move,
or perhaps more accurately, when it is on the hunt—
moving with one purpose: to find food.
Luckily for them (but not for their prey), vampyrellids have an expansive palate.
They’ve been known to consume everything from green algae to diatoms to yeast to rotifer eggs.
With such a wide menu to choose from, vampyrellids wield a number of different
strategies to capture their prey, each of which manages to sound a little bit
creepier than the last.
The least unsettling of all is free capture,
a method of eating that’s quite common throughout the microcosmos.
The vampyrellid catches their food and then swallows them up in a
food vacuole that can break down the prey to extract the nutrients they need.
It doesn't sound like a pleasant thing to go through as prey,
but it’s a method of eating that is at least familiar.
The next method though is a little more disconcerting, starting with the name:
colony invasion.
With this strategy, the vampyrellid finds its way into algae colonies,
digging past the gelatinous matrix that holds them together so that it can be surrounded by its prey.
Not only does the vampyrellid effectively take up residence in a buffet, it is able to hide out
in that colony as well, staying out of sight from other predators that might want to come after it.
It turns its prey into a shield and restaurant all at once.
Vampyrellids can also consume their prey through something
called protoplast extraction, which perhaps sounds more mundane than what it actually is.
This is the feeding strategy behind the vampyrellid’s name,
the action that Cienkowski and plenty of other scientists have witnessed and documented.
Despite the impact of this method on the scientific imagination,
we don’t actually know fully how it works.
It's controlled by the vampyrellid’s pseudopodia—
these long filaments that branch out from its body.
And the vampyrellid begins by poking or dissolving holes in their prey.
From there, they then use two feeding pseudopodia to dig into the prey cell to act like straws…
or, you might say, like vampire fangs.
And there’s actually one last vampyrellid approach to dining, though it’s quite rare.
It’s called prey infiltration, and it’s kind of like getting to the fourth entry
in a horror movie series and realizing every frightening image you’re about
to see is actually like a remix of previous terrors taken to their most gruesome end.
Prey infiltration begins similarly to protoplast extraction:
with the vampyrellid puncturing its prey.
But then it shifts into something more like colony invasion, except instead of invading the colony,
the vampyrellid invades the body of its prey to feed from within.
Imagine Dracula not just sucking blood from your neck, but somehow invading your body
through the holes left by his fangs and then consuming your blood from within.
Or maybe don’t imagine it.
Perhaps we’ve taken the metaphor a little too far.
However the vampyrellid chooses to eat, the next stage of its life is the same.
It will turn from trophozoite to cyst, retracting those long filamentous extensions inwards and
forming a cell wall around itself that might even attach to surfaces around the organism.
We’ve seen plenty of cysts in the microcosmos,
each of which iterates on some version of the same theory:
when an organism finds itself in dire environmental circumstances,
it holes up in a cyst where it winds down its metabolism and rests,
waiting for things to clear up so that it can emerge and survive.
And while vampyrellids can form that kind of resting cyst,
what we’re watching now is a very different kind of state:
this is a vampyrellid in a digestive cyst.
It hasn’t shut off its metabolism.
Quite the opposite.
The whole point of the digestive cyst is to give the vampyrellid time to break down its meals.
Some species will even change color, turning red or yellow or some other
color as its body responds to the changes brought on by the vampyrellid’s meal.
If we were to turn back to popular images of vampires,
perhaps this is the vampyrellid’s coffin, a place for it to rest while it processes the
cytoplasmic sips it took from the body of another organism.
Except even then, the stories we tell of vampires
fail to capture all of the twisted tangles of the vampyrellid’s life.
Because when the vampyrellid is done digesting, it does two things.
First it emerges from its cyst, punching holes in the walls it
used to encase itself and cycling back into its trophozoite state.
But sometimes more than one trophozoite emerges, because while the vampyrellid was in the cyst,
it might have divided once, twice, maybe even more times.
And second, the vampyrellid gets rid of its undigested food remains,
leaving behind what scientists have described as “numerous brown particles.”
So again, if we were to try to put this in vampire terms,
imagine a vampire ready to emerge from its coffin at night.
It’s digested its meals, it is ready to hunt.
But first, the vampire needs to clone itself a few times.
And then, with its bloodthirsty clones,
our vampire will proceed to punch holes in its coffin until they can climb out.
And then, before they get ready to hunt, they do have to poop.
When Cienkowski decided to give the vampyrellids their name,
did he imagine taking the metaphor this far?
We don’t know, but we hope so.
We hope that somewhere out there
are the ghosts of a 19th century conversation between biologists,
perhaps arguing the merits of comparing these tiny organisms to a legendary figure.
And perhaps they settle on understanding that sometimes the only way to describe the
fantastical worlds we see is to turn to the fantastical creatures we imagine.
And to wonder what other monsters we can find.
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A world that we all get to occupy together even if we
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But that's a shame.
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If you want to see more from our Master of Microscopes, James Weiss,
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