No fossils unambiguously assigned to genus
Lepomis are currently known from the putative stem-lineage that must have existed between 25 and 15 million years ago, spanning most of the
early Miocene. Currently, four extinct species of
Lepomis are known from the fossil record: There are at least two as yet undescribed fossil species of
Lepomis that reach back to the
middle Miocene: • †
Lepomis sp. A consists of fragmentary fossils of its lower jaw from the
Valentine Formation of Nebraska, dated to 13.5 million years ago, and shows morphological similarities to the modern
Lepomis microlophus, although its great age means that this species predates the divergence of any of the living species. • †
Lepomis sp. B was found in deposits from the
Ogallala Formation of Kansas, dated to 12 million years ago. Two other more recent fossil species appear to be closely allied to
Lepomis gulosus, and indeed their earliest occurrence may be close to the divergence of the lineage leading to the modern warmouth from other species of
Lepomis: • †
Lepomis kansasensis lived 6.6 million years ago in the Ogallala Formation of Kansas, and had
pterygoid teeth, indicating a close relationship to the warmouth. • †
Lepomis serratus is known from 3.4 to 2.0 million year old deposits in the
Keim Formation of Nebraska, and also appears to be closely related to or ancestral to the warmouth on the basis of its
preopercle. ==Species==