Jardine, N., 1969, "The Observational and Theoretical Components of Homology: A Study on the Morphology of the Dermal Skull-Roofs of
Rhipidistian Fishes", Biological Journal of the Linnean Society, vol.
They also described a portion of the lower jaw of a probable rhipidistian (crossopterygian) fish; the first of its kind found in Michigan.
Unfortunately, identifying the specific taxa that produced them is not possible, but their association with various fossils from acanthodian, actinopterygian, sarcopterygian, and rhipidistian (crossopterygian) fish suggests that any of these are potential sources of the coprolites and nonspiraled cololites.
No transitional forms are known between the early amphibian limb and the presumed
rhipidistian ancestors.
In contrast, the skeleton of the Devonian
rhipidistian fish Eusthenopteron is extremely complex, incorporating elements of many different structural types, especially in its cranial architecture (Fig.
Rhipidistians (Sarcopterygii) from the Hunter Siltstone (Late Famennian) near Grenfell, NSW, Australia.
No fish--including the
rhipidistians, (7) who first braved solid ground had any bony articulation between the skull and the vertebral column.