An early actinopterygian fish from the Catskill formation (Late Devonian, Famennian) in Pennsylvania, USA

A new taxon of early actinopterygian fish is described from the Late Devoni an Catskill Formation in Pennsylvania. Limnomis delaneyi, new genus and spe cies, is preserved in a plant-rich, greenish-gray siltstone representing an overbank pond facies. Several hundred partial specimens have been collecte d and preservation is restricted to dermal skeletal elements. Features of t he skull such as a T-shaped dermosphenotic that contacts the nasal, an inte rtemporal that does not contact the nasal, a rostral that contributes to th e jaw margin, and the absence of suborbitals and supraorbitals indicate tha t this taxon is part of the stem lineage of actinopterans. Reconstructions of the skull and body of this fish are presented.