Phylogeography and Biogeography of the Ubiquitous and Unique Sciaenid Genus \u3ci\u3eAplodinotus\u3c/i\u3e in North America

Aplodinotus grunniens represents one of the most common, widespread, and unique freshwater fishes in North America. Understanding the evolutionary history of this sciaenid is challenging though as published palaeontological records are lacking. Existing literature documenting skeletal remains and otoliths is summarised herein to better understand divergence and biogeography of the extant A. grunniens and extinct Aplodinotus species. Fossil evidence indicates that in addition to A. grunniens, three putative, extinct, marine species in North America and two in South America existed. The North American fossil Aplodinotus range from Oligocene to early Miocene, while the genus extends to the middle Miocene in South America. All described extinct fossil Aplodinotus have been recovered from shallow marine sediments with the oldest from the U.S.A. Gulf Coastal Plain. All sites with extant A. grunniens are from freshwater deposits ranging from middle to late Miocene to Holocene in age which very closely approximate the modern geographic distribution and include a variety of preserved skeletal elements and otoliths. The disappearance of the fossil marine Aplodinotus in the early Miocene in the Gulf is interpreted to represent the genus’ transition to brackish and eventually freshwater habitats and development of the extant species by the late Miocene