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A collection of fossil fish teeth and other elements from Eocene deposits on the northshore of Birket Qarun, Fayum Depression, Egypt, is reported. This collection adds significantly to our knowledge, as it consists of material that was screened from the sediments, allowing collection of small teeth that represent taxa not previously reported from the Fayum. Previous collections from these sediments have concentrated on larger remains that generally represent elasmobranchs, which are marine species from deposits lower in the section. Most of this material, collected by screening at the Birket Qarun 2 (BQ-2) locality, represents fully freshwater fishes. It includes the first record of the mormyrid Gymnarchus in the Fayum Depression, which represents the oldest record for this group, known previously only from the late Miocene or younger deposits. Similarly, Mochokidae (Siluriformes) and Hydrocynus (Alestidae) remains from the site are the oldest record of these taxa. Other taxa recovered are the os...

A single specimen of the anterior portion of a small fish was collected from the Eocene Mahenge site of Tanzania in 1996. The specimen, preserved as part and counterpart natural mold, is identified as belonging to a characiform fish, although the presence of a Weberian apparatus has not been confirmed beyond doubt. Features of the bones, such as the prominent lateral ridge on the anterodorsal corner of the opercle, the fused postcleithra 2+3, and the lack of a dentary symphyseal hinge, indicate that the fish is related to the Citharinidae and Distichodontidae. The fossil cannot be included in any known genus, and is described here as a new genus and species, Eocitharinus macrognathus. The fossil record of characiforms includes few articulated skeletons, of which only one had been reported previously from Africa, described in the family Characidae (=Alestidae).

Alestidae is a clade of African characiform fishes including 19 extant genera and approximately 105 species that are known from Afro-Arabia, with records reported from the Eocene-Oligocene Jebel Qatrani Formation of Egypt, the Eocene Mahenge crater lake of Tanzania, and early Oligocene to Miocene sites on the Arabian Plate. Here we report the first record of alestid fishes from the late Oligocene Nsungwe Formation in the Rukwa Rift Basin of southwestern Tanzania. The Nsungwe alestid sample is composed of 92 teeth spanning a range of sizes and morphologies. Teeth are examined with regard to cusp number and organization, tooth position and replacement, and in the context of alestid jaw organization using modern, comparative representatives. Results suggest that at least two alestid taxa are represented in Nsungwe Formation localities. Hydrocynus teeth exhibit a single, conical cusp. Several of these specimens preserve a mesiodistally expanded crown and concave surface on the lingual aspect of the t...