A large, freshwater chanid fish (Ostariophysi: Gonorynchiformes) from the Upper Cretaceous of MadagascarCitation for this article: Murray, A. M., Brinkman, D. B., Friedman, M., & Krause, D. W. (2023) A large, freshwater chanid fish (Ostariophysi: Gonorynchiformes) from the Upper Cretaceous of Madagascar. Journal of Vertebrate Paleontology . https://doi.org/10.1080/02724634.2023.2255630

Abstract

ABSTRACTIsolated fossil bones from freshwater Upper Cretaceous (Maastrichtian) deposits in the Mahajanga Basin of northwestern Madagascar are identified as belonging to a gonorynchiform fish. Multiple elements representing the same bone, including opercles, hyomandibulae, frontals, and basioccipitals, indicate that only a single gonorynchiform species is present. The most diagnostic element is here named as a new genus and species, †Vango fahiny; the other elements likely belong to the same taxon. The Madagascan gonorynchiform material shares features with members of the subfamily Chaninae and is assigned to that group. It is similar to the extant milkfish Chanos chanos but can be easily distinguished from that species by numerous features, such as the basioccipital and maxilla being relatively shorter than those of C. chanos, and the opercle being overall rounder and having a shorter auricular process. The presence of a chanid in Madagascar in the Maastrichtian most likely represents an invasion of a marine lineage into fresh waters. The previously known Cretaceous fossils of gonorynchiforms are spread throughout the Tethys Sea in mid-latitude to northern regions from the east (e.g., Lebanon, Europe) through to the southwest (e.g., Mexico, Brazil). †Vango faniny gen. et sp. nov. represents the first Mesozoic/Paleogene record of gonorynchiforms in East Gondwana, comprising primarily Antarctica, Australia, Madagascar, and the Indian subcontinent. ACKNOWLEDGMENTSWe thank the ministries of Mines, Higher Education, and Culture of the Republic of Madagascar and the Mention Bassins Sédimentaires Evolution Conservation of the Université d’Antananarivo for permission to conduct research in Madagascar, and the Madagascar Institut pour la Conservation des Ecosystèmes Tropicaux and the villagers in the Berivotra and Lac Kinkony study areas for logistical support of fieldwork; A. Lownsdale, K. MacKenzie, S. Pevsner, and S. Swenson for assistance with cataloging specimens; and B. Rakotozafy for assistance with Malagasy names. We are also grateful to D. Mayrinck, and two anonymous reviewers for providing constructive criticisms of the manuscript, and to phylogenetics editor P.L. Godoy and handling editor T. Argyriou for their efforts. This research was supported by grants from the National Science Foundation (DEB-9224396, EAR-9418816, EAR-9706302, EAR-0106477, EAR-0446488, EAR-1123642, EAR-1528273, EAR-1664432, and DBI-2242716) and the National Geographic Society (6400-99, 6940-00, 7645-04, 8597-09, 9057-12), and the David B. Jones Foundation to DWK. Museum research trips to Denver were supported by Natural Sciences and Engineering Research Council of Canada Discovery Grant 327448 (AMM), and patrons of the Denver Museum of Nature & Science (DBB).AUTHOR CONTRIBUTIONSAMM, DBB, and DWK designed the project. AMM developed the first draft of the manuscript and all authors contributed sections as well as editing. MF first recognized the presence of a gonorynchiform in the fauna and AMM and DBB identified additional elements. AMM conducted the phylogenetic analysis.SUPPLEMENTARY FILESSupplementary Data 1: nexus file used in the phylogenetic analysis.Supplementary Data 2: the most parsimonious trees resulting from the phylogenetic analysis.Supplementary Data 3: the 50% majority-rule and strict consensus trees from the phylogenetic analysis.