New Oligocene Pseudocrenilabrinae cichlid fishes (Teleostei, Cichlidae) from freshwater deposits of Libya

Abstract

Two species of fossil cichlid are described from Oligocene deposits of Libya. One is formally described as Libyachromis fugacior gen. et sp. nov. This species is considered to be the sister group to most of the remaining members of the African subfamily Pseudocrenilabrinae, perhaps close to Heterochromis, and is characterized by two predorsal bones, dorsal fin with 12–14 spines and 9–12 rays, 24–28 vertebrae, cycloid scales present on body and head including cheek, and only unicuspid teeth present on the oral and pharyngeal jaws. The second fossil form is less complete, and so we do not formally name it, but it appears to be most closely related to Tylochromis, and thus we place it in the Tylochromini. These new fossils increase our understanding of the diversity of cichlid lineages in the Palaeogene. The unnamed fossil supports the presence of Tylochromini in the Eocene and Oligocene of North Africa, as was previously suggested by the remains of partial lower pharyngeal jaws from Egypt and Libya. The named fossil adds to the known diversity of early Cenozoic cichlids that document the presence of probably Heterochromini along with Tylochromini in North Africa.

http://zoobank.org/urn:lsid:zoobank.org:pub:435CD980-E4DB-4333-AB21-BDA38F9C6023

Keywords:

• Palaeogene
• North Africa
• Cichlidae
• Heterochromini
• Tylochromini
• fossil fish

Acknowledgements

We thank two anonymous reviewers and the editors for their comments that improved the manuscript. This work was financially supported by the Institute of Geology of the Czech Academy of Sciences (RVO67985831). Pavel Lisý (Prague) is acknowledged for preparation of some photos. Martin Mazuch, Martin Košťák and Katarina Holcová (Prague) are acknowledged for access to the collection of the Institute of Geology and Palaeontology (Faculty of Science, Charles University) and loan of the specimens. Pavel Bokr (Prague) is acknowledged for help with the measurement software.

Supplemental material

Supplemental material for this article can be accessed here: https://doi.org/10.1080/14772019.2022.2033861.

Associate Editor: Martin Brazeau