So 43 states in the union have official state fossils. It apparently not being enough to lay claim to all manner of flora and fauna, the need was felt by some that each state must also designate which calcified skeleton best represents it.
Some states picked their most prestigious corpse on the basis of campaigns from scientists or students. Usually they seem to prefer something that was first found in that state. My own home has selected Acrocanthosaurus atokensis for that honor. Evidence of this dinosaur was first found in Atoka County in the 1940s, and parts of another skeleton were found in another county some 40 years later. It was something like a T. rex, but several million years older. While perhaps more accurate, it was decided "Getoffmylawnosaurus" didn't sing and so it was discarded.
Of interest in the original Atlantic article is the designated fossil for the District of Columbia -- which is not, surprisingly enough, Charlie Rangel. Nor was it Strom Thurmond, although both are excellent candidates. No, it's something called Capitalsaurus. Which is not an official name -- and since the fossil evidence for it currently consists of two vertebrae, there's every chance in the world that it will turn out to be part of another dinosaur that's already known.
If it does turn out to be a distinct animal, it will hold another distinction as the last known vertebrate ever found in Washington, D.C.