[News] Did trilobites hide from nautiloids?


TONMO Supporter
Nov 19, 2002
Here's details of an interesting find from Ordovician Sweden, trilobites contained within fossilised tunnels they had dug. Were they hiding from nautiloid predators or is there another explanation?

Food for thought.

Nautiloid thoughts:
  • Trilobite dinner
  • How do I get into that tunnel
  • Why dont trilobites just stay on the surface
Trilobite thoughts:
  • Ha ha, cant get me now
  • Where is that big worm that really lives in here?

Food for thought
thoughts of food
thoughts of being food
How about: "Did trilobites hide from nautiloids inside of nautiloids?"

Here are photos of a Devonian fossil I found last summer - a trilobite inside an orthocone nautiloid. Apparently the association is known; it's thought that the trilobites hid inside to molt.
Internal mold of Michelinoceras? with trilobite Eldredgeops (Phacops). The length of the nautiloid fossil is 190mm.


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ob;77399 said:
Think giant bristleworms (rekindling nightmares), think Permian extinction...

I have a coral book that contains a photograph of a giant bristleworm species removed from a persons reef tank. It was 5 feet long... looked like a giant centipede. I can see one of those making dinner out of a trilobite. Shoot... I can see one of those making dinner out of a nautilus. Nightmare material for sure. I wouldn't be hiding in it's hole!
Thanks for posting that picture Tornoceras.

It had me totally freaked out for a while... how could a trilobite get inside the phragmocone of a nautiloid? The same way the sediment that is filling the chambers did, the shell and/or the septa were broken so the trilobite could climb in and hide or molt, then the sediment filled the shell trapping the trilobite or its molt inside the shell. A very nice find, telling a cool story. :cool2:
Mote had a bristleworm display (living) that contained critters I would not want to find growing in my tank (they were at least an inch wide).
didn't Mote also have an exhibit of "fireworms" or something like that which had some nasty sting? I've only SCUBA'ed in the Pacific, but I flagged those as something to learn to recognize if I dive in the Atlantic (particularly considering my propensity to flip over rocks to find the interesting invertebrates) yup, google confirms they are a type of bristleworm: http://marinebio.org/species.asp?id=292 :goofysca:

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