[4] While seeing fossil collections of the Earl of Enniskillen and Philip Grey Egerton, Louis Agassiz identified fragments of a giant fish (praised by him then as "marine giant") from the Yorkshire Lias in the 1830s, referring them to Coelacanths and naming it "Gyrosteus" without any referred species in 1834, back then a nomen nudum, as he never described or illustrated the materials.

[7] Arthur Smith Woodward thoroughly described Gyrosteus mirabilis in 1889-90, distinguishing it from Chondrosteus based on dermal bone patterns and branchial structure.

A partial skull roof was noted but its elements remained poorly understood, with significant material loss due to pyrite decay.

[8] SMNS 97274, a skull roof referred Gyrosteus mirabilis preserved in a mudstone slab, records most of the rostral bones in a mosaic arrangement, similar to other chondrosteid fishes, with some sections mostly absent due to damage.

Authors also pointed out that a modern redescription and phylogenetic analysis of both Strongylosteus and Gyrosteus is still necessary to clarify their evolutionary relationships within Chondrosteidae.