Category Archives: Merostomata

Organism of the Day: Mixopterus

Today, I bring you the long extinct genus, Mixopterus. Because sometimes, Evolution dabbles with the fabric of Nightmares.


Click on it and play the music from Psycho for full effect!

This is the species Mixopterus kiaeri. Some of you may have questions like, “Is that thing a scorpion?”, “…is that monster is almost 2 feet long?”,  “Will this hell-spawn haunt my waking dreams?”, or “HOLY CRAP! IS THAT A MURDER SPIKE ON IT’S TAIL????”. The answer to all of these questions are, respectively, maybe, yes, most likely, and ohhhhhhhhhhh yes it is. Thankfully, no human has ever come in contact with a living Mixopterus. It is now my great pleasure to inform you that it is dead, and has been dead, for 354 million years, and we had no idea of it’s existence until we found some in the rocks (the above comes from Norway). These things are part of the Order Eurypterida, which were scorpion-looking arthropods who roamed the vast seas of the Late Silurian Period. For reference, plants had just begun to come up on land, but animals were unheard of. That is part of what makes eurypterids so special; Some believe that they may have made short trips on land at a time where essentially no animals were up there. The body plan is that of a versatile predator. It had powerful muscles, legs, and paddle-like structures, meaning that it could walk on the ocean floor or swim to cover more distance. It’s spike was probably used to attack prey (some speculation says it may have had poison in it). They had large pincers, with long sharp spines, that could hold a prey down. The prey? Trilobites, a common arthropod for hundreds of millions of years. It is possible that this may be the ancestor of scorpions, which in my opinion, are a lot less terrifying than this dude, and, to be honest, slightly less badass.


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