I have pliocene fossilised nests of wattle pigs, often mis-labelled by dealers as "sea wasp nests" I dont know how a jellyfish could make a nest out of clay and saliva, a subject for The speculative Dinosaur Project maybe?
Not sure, I guess the resemblance to a mud wasp pupa is pretty strong. The sign on that blog I showed you did get the species name right, but somehow still called them sea wasps...
I have seen fossil bee pupa cases for sale online that look similar, but are smaller.
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I swear, when I bought one as a kid, they were called that. When I saw them in later years, I always thought they were from wasps...
I have seen fossil bee pupa cases for sale online that look similar, but are smaller.