Data from: Virtual reconstruction of endocast anatomy in early ray-finned fishes (Osteichthyes: Actinopterygii)

Cranial endocasts, infillings of the skeletal void that once contained the
brain and associated soft tissues, represent detailed anatomical
structures that have long been the focus of paleontological investigation.
We applied computed tomographics (CTs) in order to generate endocast
models for the Paleozoic actinopterygian fishes Mimipiscis and Kentuckia,
which serve as key representatives of anatomically primitive, early ray
fins in analyses of early vertebrate relationships. The resultant
endocranial models generally corroborate existing accounts of endocranial
anatomy in these genera, drawn from descriptions of the inner face of the
brain cavity. However, the endocasts also provide new anatomical details,
the most significant of which are the presence in Mimipiscis of widely
divergent olfactory tracts, small optic lobes, and anterior and posterior
semicircular canals that extend dorsal to the roof of the endocranial
chamber. By contrast, Kentuckia possesses a single, straight olfactory
tract, wide optic lobes, and anterior and posterior semicircular canals
that do not reach the dorsal surface of the endocast. In each of these
features, Kentuckia resembles stratigraphically younger actinopterygians
such as Lawrenciella and Kansasiella, whereas Mimipiscis more closely
resembles sarcopterygians and other outgroups. This character distribution
provides further support for earlier phylogenetic interpretations of these
genera.