Fossil Record 20(1): 47-67, doi: 10.5194/fr-20-47-2017
The lower actinopterygian fauna from the Lower Carboniferous Albert shale formation of New Brunswick, Canada – a review of previously described taxa and a description of a new genus and species
expand article infoKathryn E. Mickle
‡ College of Science, Health, and the Liberal Arts, Philadelphia University, 4201 Henry Ave, Philadelphia, PA 19114, United States of America
Open Access
The Lower Carboniferous Albert shale formation of New Brunswick, Canada, iswell-known for the preservation of countless articulated loweractinopterygian palaeoniscoid fishes. This site is at the boundary betweenthe Devonian and the Lower Carboniferous, making the lower actinopterygianspreserved at this site important. The taxonomic history of previouslydescribed Albert shale formation actinopterygians is reviewed here. Many ofthe earliest described actinopterygian taxa from the Albert Formation arerepresented by poorly preserved type specimens and have the distinction ofbeing moved from one paraphyletic genus to another paraphyletic genus. Whilethese taxa are in need of major redescriptions, such work is premature untilthe large paraphyletic or polyphyletic genera they have been placed in,Palaeonicus[m], Rhadinichthys, andElonichthys, are redescribed. But there is new diversitywithin the Albert shale formation. Here, a new lower actinopterygian species,Lambeia pectinatus, is described from one well-preservedspecimen. This new species is characterized by dorsal ridge scales withpectinated posterior margins, body scales inserted between adjacent dorsalridge scales, body scales with pectinated posterior and ventral margins, thepresence of a ventral rostro-premaxilla and a median rostral bone, a separateand distinct antorbital bone, and a single supraorbital bone. This newlydescribed species is distinct from previously described fishes from theAlbert Formation, and the morphology of this newly described species is moresimilar to later Carboniferous fishes rather than Devonian fishes. Thissuggests that morphological features commonly seen in Carboniferous fishesand rarely seen in Devonian fishes were present early in the Carboniferous.