The Eocene was a key interval for the diversification of squamates worldwide. However, little is known about their early evolution in Africa due to the scarcity of Paleogene fossil squamates from that continent. One of the most important Eocene vertebrate assemblages in Africa is known from the Fayum Depression of Egypt, but only a few lizards and snakes have been reported from these deposits. Here we report the first Paleogene record of the clade Amphisbaenia in Egypt, from the lowest upper Eocene Birket Qarun Locality 2 (BQ-2). It corresponds to a mid-trunk vertebra characterized by a depressed centrum with a flattened base, hemispherical synapophyses, and absence of a neural spine. Additional material from BQ-2 includes seven vertebrae attributed to colubroidean snakes. One trunk vertebra resembles those of early Eocene Procerophis from India while the remaining colubroidean vertebrae are referred to Renenutet enmerwer. Caudal vertebrae of Renenutet are described here for the first time. Similarities in the caudal vertebral morphology between BQ-2 Renenutet and Thaumastophis missiaeni from the lower Eocene of India reinforce the hypothesis of a close affinity between them. The presence of cf. Procerophis and Renenutet in Egypt adds to the evidence for terrestrial faunal exchange between Asia and northern Africa during the early/middle Eocene along the southern margin of the Tethyan Sea.

A massive block of decorative limestone destined for countertops or sidewalks was cut in a stonecutting yard in Shaq El-Thoaban (Cairo, Egypt), and it was discovered to be riddled with what appeared to be fossilized bones. The limestone block had already been cut into five thick slabs about 4.5 cm thick, and each saw cut removed 3.3 mm of limestone between adjacent plates, inadvertently creating an almost perfect cross-section of what has been identified as a protocetid whale. Protocetidae is a group of extinct whales that fall in the middle of the evolutionary transition of whales from land to sea. Investigation indicates that the block came from Gebel Hof Formation, of Bartonian late middle Eocene age (ca. 42 Ma), north of Khashm el-Raqaba in Wadi Tarfa, Eastern Desert of Egypt, the same locality that had produced the protocetid Aegyptocetus tarfa. The new specimen (MUVP 502) is an associated partial skeleton represented by a complete cranium, dentaries, many vertebrae, a humerus, an ulna, several ribs, and other unidentified elements. Unique preservation allows the examination of some internal anatomical features of the skull along with its external morphology. The hallmark characters that distinguish MUVP 502 from other protocetids include a large skull, measuring over 92 cm, larger than any previously described protocetid; large and robust premolars and molars, larger than any previously described African protocetid; short and fused mandibular symphysis, ending just after the posterior margin of the canine; thinning of the lateral walls of the mandibles; and enlarged mandibular canals. Comparison with related taxa suggests that MUVP 502 represents one of the largest protocetid whales on record. This size may have allowed MUVP 502 to hunt larger prey within its environment and therefore shifts its role in the ecosystem to that of a semi-aquatic apex predator. In addition to shedding light on a unique taphonomic window, this specimen also delivers an exceptional opportunity for a thorough morphometric assessment over time of morphological trends in earlier cetaceans.

Background The rich rodent assemblages from the Eocene–Oligocene deposits of the Jebel Qatrani Formation (Fayum Depression, Egypt) have important implications for our understanding of the origin and paleobiogeography of Hystricognathi, a diverse clade that is now represented by the Afro-Asiatic Hystricidae, New World Caviomorpha, and African Phiomorpha. Methods Here we present previously undescribed material of the enigmatic hystricognath clade Phiocricetomyinae, from two stratigraphic levels in the lower sequence of the Jebel Qatrani Formation—a new genus and species ( Qatranimys safroutus ) from the latest Eocene Locality 41 (~34 Ma, the oldest and most productive quarry in the formation) and additional material of Talahphiomys lavocati from that species’ type locality, early Oligocene Quarry E (~31–33.2 Ma). Results The multiple specimens of Qatranimys safroutus from L-41 document almost the entire lower and upper dentition, as well as mandibular fragments and the first cranial remains known for a derived phiocricetomyine. Specimens from Quarry E allow us to expand comparisons with specimens from Libya (late Eocene of Dur at-Talah and early Oligocene of Zallah Oasis) that have been placed in T. lavocati , and we show that the Dur at-Talah and Zallah specimens do not pertain to this species. These observations leave the Fayum Quarry E as the only locality where T. lavocati occurs.

Over about 10 million years, the ancestors of whales transformed from herbivorous, deer-like, terrestrial mammals into carnivorous and fully aquatic cetaceans. Protocetids are Eocene whales that represent a unique semiaquatic stage in that dramatic evolutionary transformation. Here, we report on a new medium-sized protocetid, Phiomicetus anubis gen. et sp. nov., consisting of a partial skeleton from the middle Eocene (Lutetian) of the Fayum Depression in Egypt. The new species differs from other protocetids in having large, elongated temporal fossae, anteriorly placed pterygoids, elongated parietals, an unfused mandibular symphysis that terminates at the level of P3, and a relatively enlarged I3. Unique features of the skull and mandible suggest a capacity for more efficient oral mechanical processing than the typical protocetid condition, thereby allowing for a strong raptorial feeding style. Phylogenetic analysis nests Phiomicetus within the paraphyletic Protocetidae, as the most basal protocetid known from Africa. Recovery of Phiomicetus from the same bed that yielded the remingtonocetid Rayanistes afer provides the first clear evidence for the co-occurrence of the basal cetacean families Remingtonocetidae and Protocetidae in Africa. The discovery of Phiomicetus further augments our understanding of the biogeography and feeding ecology of early whales.

The Paleocene-Eocene thermal maximum (PETM) was a short interval (120–220 k.y.) of elevated global temperatures, but it is important for understanding biotic responses to climatic warming. Consequences of the PETM for marine fishes remain unclear, despite evidence that they might have been particularly vulnerable to increasing temperatures. Part of this uncertainty reflects a lack of data on marine fishes across a range of latitudes at the time. We report a new paleotropical (~12°N paleolatitude) fish fauna from the Dababiya Quarry Member of Egypt dating to the PETM. This assemblage—Ras Gharib A—is a snapshot of a time when tropical sea-surface temperatures approached limits lethal for many modern fishes. Despite extreme conditions, the Ras Gharib A fauna is compositionally similar to well-known, midlatitude Lagerstätten from the PETM or later in the Eocene. The Ras Gharib A fauna shows that diverse fish communities thrived in the paleotropics during the PETM, that these assemblages shared elements with coeval assemblages at higher latitudes, and that some taxa had broad latitudinal ranges substantially exceeding those found during cooler intervals.