An earliest Paleocene squirrelfish (Teleostei: Beryciformes: Holocentroidea) and its bearing on the timescale of holocentroid evolution

Abstract

The record of articulated marine fish fossils during the latest Cretaceous and earliest Cenozoic is sparse. The oldest-known definitive squirrelfishes and soldierfishes, like the first examples of many extant reef-dwelling clades, are known from early Eocene deposits of Europe. Here, we describe a new genus and species of holocentroid (Teleostei: Beryciformes: Holocentroidea) based on material from three individuals from early Paleocene (Danian) deposits of New Jersey, USA using micro-computed tomography. The specimens comprise a three-dimensionally preserved skull and partial postcranium, plus two isolated neurocrania. The new taxon, †Iridopristis parrisi, possesses a unique combination of characters, including a heterosulcoid otolith morphology and an edentulous premaxillary tooth-gap, while lacking a newly proposed character for the remainder of Cenozoic holocentroids: a lamina on the lateral surface of the anguloarticular, anterior to the jaw joint. Bayesian phylogenetic analysis of morphological, stratigraphical and molecular data under the fossilized birth-death process finds that the new taxon branches from the holocentrid stem, where it is joined by two of the three squirrelfish genera from the early Eocene (Ypresian) of Bolca, Italy. We estimate a Danian divergence between Myripristinae and Holocentrinae, the two reciprocally monophyletic subfamilies of Holocentridae. Our analysis suggests that several holocentroid lineages crossed the Cretaceous–Palaeogene boundary.

http://zoobank.org/urn:lsid:zoobank.org:pub:0B458336-EFCF-46D0-98D0-CE5AD371D7AF

Keywords:

• Acanthomorpha
• Cretaceous–Palaeogene boundary
• squirrelfishes
• computed tomography
• Bayesian phylogenetics
• parsimony

Acknowledgements

We thank two anonymous reviewers for their helpful feedback, as well as the editorial board of the Journal of Systematic Palaeontology for their patience and assistance in formatting this manuscript. We thank D. C. Parris, D. Ehret and R. Pellegrini (NJSM GP) for access to the material herein described. We thank W. Simpson and L. Grande (FMNH) for access to comparative fossil materials, and D. Nelson and R. Singer (UMMZ), M.H. Sabaj and M. Arce-H. (ANSP), and S. Mochel and C. McMahan (FMNH) for access to extant comparative materials. Collections support from A. Rountrey, B. Dergis and L. Sandefur (UMMP) was necessary for the completion of this project. D. Goodvin greatly assisted with the µCT segmentation process. Discussions with G. Carnevale, D. C. Parris and A. Capobianco aided in phylogenetic reconstruction and constraining ages of taxa included in the analysis. Generation of renders was greatly aided by the instruction of A. Capobianco and R. T.-Figueroa. This study includes data produced in the CTEES facility at University of Michigan, supported by the Department of Earth & Environmental Sciences and College of Literature, Science, and the Arts. This work was supported in part by the University of Michigan Department of Earth and Environmental Sciences (Scott Turner Award to J.V.A.), University of Michigan Rackham Graduate School (Rackham Merit Fellowship to J.V.A.), the Society of Systematic Biologists (Graduate Student Research Award to J.V.A.), and the Paleontological Society (Harry B. Wittington Award to J.V.A.).

Supplemental material

Data associated with this study are available on Figshare (10.6084/m9.figshare.21754541). Supplemental material for this article can be accessed here: https://doi.org/10.1080/14772019.2023.2168571

Associate Editor: Martin Brazeau