Swept from tall grass understory of pine forest. Thinking Pyrgocorypha uncinata.

Edit: Has gotten a big bigger in captivity (on diet of carrot and fish flakes). There is no evidence of a hook to the tip of the cone, which would seem to rule out both Belocephalus and Pyrgocorypha. That leaves Bucrates, of which there is only one species in range that should be in cattail marshes (definitely not where this little conehead was found), and Neoconocephalus, of which there is only one species that doesn't overwinter as eggs, N. triops. I found nearly mature nymphs and adults of that species in the vicinity, so I doubt it's that species. Not really sure what this is!