A fish assemblage from an early Miocene horizon from Jabal Zaltan, Libya (original) (raw)

A Fish Assemblage from the Middle Eocene from Libya (Dur At-Talah) and the Earliest Record of Modern African Fish Genera

PLOS ONE, 2015

In the early nineteen sixties, Arambourg and Magnier found some freshwater fish (i.e., Polypterus sp., Siluriformes indet. and Lates sp.) mixed with marine members in an Eocene vertebrate assemblage at Gebel Coquin, in the southern Libyan Desert. This locality, aged ca 37-39Ma and now known under the name of Dur At-Talah, has been recently excavated. A new fish assemblage, mostly composed of teeth, was collected by the Mission Paléontologique Franco-Libyenne. In this paper, we describe freshwater fish members including a dipnoan (Protopterus sp.), and several actinopterygians: bichir (Polypterus sp.), aba fish (Gymnarchus sp.), several catfishes (Chrysichthys sp. and a mochokid indet.), several characiforms (including the tiger fish Hydrocynus sp., and one or two alestin-like fish), and perciforms (including the snake-head fish Parachanna sp. and at least one cichlid). Together with the fossiliferous outcrops at Birket Qarun in Egypt, the Libyan site at Dur At-Talah reduces a 10-Ma chronological gap in the fossil record of African freshwater fish. Their fish assemblages overlap in their composition and thus constitute a rather homogenous, original and significant amount of new elements regarding the Paleogene African ichthyofauna. This supports the establishment of the modern African freshwater fish fauna during this time period because these sites mostly contain the earliest members known in modern genera.

Discovery of an earliest Pliocene relic tropical fish fauna in a newly detected cliff section (Sabratah Basin, NW Libya)

Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen, 2012

A marine tropical fauna, which survived the Messinian salinity crisis in the Mediterranean Sea, was reported from several places in post-Messinian sediments in the northern Mediterranean area (e.g. Spain, Italy, Greece, and Cyprus). In North Africa knowledge about the marine post-Messinian is very limited. Here we present a unique diverse fish fauna, which was discovered along a steep cliff at the Mediterranean Sea between the cities of Tripoli and Al Khums. The fossil fish teeth and bones found together with other vertebrate remains are concentrated in a transgressive lag on top of an erosional unconformity, which is regarded to represent the Messinian event. The majority of fossils belong to teeth of selachians (24 species) and some large actinopterygians (at least 4 species). Less common are teeth and bones of reptiles and mammals. This fish fauna allows detailed evidences relating to stratigraphy, depositional environment as well as composition and evolution of the Late Neogene fish fauna. Furthermore, the composition of the fauna gives indication about the palaeoclimate of the early Pliocene and questions the complete extension of the marine fauna during the Mediterranean salinity crisis. In particular, the association of Carcharodon and Megaselachus is clearly indicative of early Pliocene age and proves for the first time the existence of early Pliocene (post-Messinian) deposits onshore western Libya. The presence of Hemipristis, Negaprion, Rhynchobatus and Aetobatus, known elsewhere in the late Miocene, but never clearly observed in Pliocene or younger deposits along the Mediterranean coasts, suggests that the fossiliferous bed is dated into the earliest Pliocene. The faunal assemblage is in favour of a high-energy nearshore depositional environment in a tropical to equatorial climate. The presence of numerous Indo-Pacific sharks and rays during the Zanclean indicates that numerous tropical selachians, inherited from the Palaeogene Tethyan Realm, may have survived in the Mediterranean a long time after the closure of communications with the Indian Ocean.

Geology and stratigraphy of the Neogene section along the Oued Beth between Dar bel Hamri and El Kansera (Rharb Basin, northwestern Morocco) and its otolith-based fish fauna: a faunal inventory for the Early Pliocene remigration into the Mediterranean

Swiss Journal of Palaeontology, 2023

The coquina on the banks of the Oued Beth in the Rharb Basin in northwestern Morocco has long been known to be exceptionally rich in fossils. The stratigraphic position ranging from the Late Miocene to the Pliocene has been controversial, however. In the course of my master's degree field work in 1975/76, I mapped the right bank of the Oued Beth from Dar bel Hamri to El Kansera. Following multiple recent studies in the general region, I here review my results and present an updated comprehensive stratigraphic and geologic frame for the first time. The coquina near Dar bel Hamri is interpreted to be of Early Pliocene age, possibly containing some reworking of Late Miocene fossils. The coquina and other locations along the Oued Beth have yielded a rich otolith assemblage, which is described in this article. It represents the first fossil otolith-based fish fauna described from Northwest Africa and contains 96 species, 16 of which are new. The new species in the order of their description are Diaphus maghrebensis n. sp., Ophidion tuseti n. sp., Centroberyx vonderhochti n. sp., Myripristis ouarredi n. sp., Deltentosteus planus n. sp., Caranx rharbensis n. sp., Trachurus insectus n. sp., Parapristipoma bethensis n. sp., Pomadasys zemmourensis n. sp., Cepola lombartei n. sp., Trachinus maroccanus n. sp., Trachinus wernlii n. sp., Uranoscopus hoedemakersi n. sp., Uranoscopus vanhinsberghi n. sp., Spondyliosoma tingitana n. sp., and Opsodentex mordax n. sp. In addition, a new species is described from the Tortonian and Zanclean of Italy: Rhynchoconger carnevalei n. sp. Some additional otoliths are described from another Northwest Moroccan location of Early Pliocene age near Asilah, 50 km south of the Strait of Gibraltar. The Early Pliocene fish fauna from Dar bel Hamri in the Rharb Basin is also of interest, because it constitutes the nearest Atlantic fauna of the time of the reconnection of the Mediterranean with the Atlantic and may have acted as a hosting area for the remigration of fishes into the Mediterranean. Indeed, the correlation is high between the Northwest Moroccan and the well-known time-equivalent Mediterranean fish fauna, but the Moroccan fauna also contains a good proportion of putative endemic taxa and taxa with tropical West African affinities that apparently did not migrate into the Editorial handling: Lionel Cavin

First description of a Pliocene ichthyofauna from Central Africa (site KL2, Kolle area, Eastern Djurab, Chad): What do we learn

Journal of African Earth Sciences, 2009

This is the first extensive study of a freshwater fish fauna from a Pliocene site in Central Africa, based on fossils collected at the KL2 site in the fossiliferous area of Kolle (Lower Pliocene, Chad). A relatively high fish diversity is revealed, confirming the presence of 19 taxa: Tetraodontidae (Tetraodon sp.). The aquatic environment corresponding to the fossil fish assemblage might be a floodplain crossed by well-oxygenated open waters. Compared with a contemporaneous East African region, the mid-Pliocene Chadian fish diversity reveals a certain endemicity, while connections between the Niger and the Chadian basin are suspected because of the presence of a freshwater ariid fish in Kolle. j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / j a f r e a r s c i attribute the fish remains from KL2. Following Fara et al. (2005), we have attempted to evaluate the influence of taphonomic imprint on the fossil ichthyofauna before discussion on the palaeoenvironment of the site and on the putative paleobiogeographic relationships of this Pliocene Chadian ichthyofauna.

Biogeographic implications of fossil fishes from the Awash River, Ethiopia

Journal of Vertebrate Paleontology, 2017

The late Miocene and Pliocene Middle Awash fish fauna is one of the earliest known Neogene fish faunas in eastern Africa and is the earliest known from the Horn of Africa. The fauna was recovered as part of the Middle Awash research project, which was designed to investigate the Mio-Plio-Pleistocene deposits along the shores of the Awash River, Ethiopia. Remains of eight fish taxa were recovered: Clarotes, Cichlidae, and Parachanna, which are native to the African continent where they have a long fossil record, and cf. Labeo, Barbus, Labeobarbus, Bagrus, and Clarias, whose origins were in Asia. These genera and families are all extant; however, certain fossil elements of cf. Labeo and Bagrus differ morphologically from modern species. When and how the Asian-derived taxa moved into Africa is enigmatic. The Middle Awash fossil deposits are located within the Horn of Africa, long suggested as a possible crossing point between Africa and the Arabian Peninsula in the late Miocene. Data presented in this paper suggest that in the late Miocene, the Horn of Africa region was accessible from the southern Arabian Peninsula via the Bab el-Mandeb Strait land bridge, which was (only) viable in the late Miocene. This land bridge has been implicated in the migration of other freshwater and terrestrial animals between Africa and Arabia. The subsequent movement of Barbus sp., Labeobarbus sp., Bagrus sp., and Clarias sp. into eastern Africa had a large impact on the diversity and abundance of later populations of African freshwater fish.

Description and paleobiogeographical implications of new Semlikiichthys (Teleostei, Perciformes) fish material from the Late Miocene deposits of Sahabi, Libya

Geobios, 2012

Fossils recently found in the Late Miocene of Sahabi, Libya, are attributed to the extinct species Semlikiichthys rhachirhinchus. This study enriches our knowledge of the anatomy of this species. The hyomandibula and, putatively, the operculum are for the first time attributed to Semlikiichthys. The fragile laminar supraoccipital crest in the dorsicranium is preserved complete. The material from Sahabi described here extends the Late Miocene distribution of the species to the north and west to include Libya. The paleobiogeographic distribution of Semlikiichthys in Africa, and the freshwater faunal connections between different hydrographical basins in north central Africa, are discussed. ß

The fishes of Bukwa, Uganda, a lower Miocene (Burdigalian) locality of East Africa

Journal of Vertebrate Paleontology, 2017

Renewed research at the early Miocene fossil site of Bukwa in northeastern Uganda has resulted in new fossil finds, including fish, with representatives of two families, Cichlidae and Alestidae. Although the two families were previously briefly reported from Bukwa, we here give a more detailed account of the fishes based on newly collected material. The cichlid material, mainly composed of vertebrae, can be tentatively assigned to one or more species of Pseudocrenilabrinae. The alestid material, comprising a diversity of teeth, likely represents several different species of Alestes, Brycinus, and/or Bryconaethiops. Although the ichthyofaunal diversity of Bukwa is low, the fishes are important for indicating the paleoenvironment and hydrographic connections of Bukwa. The early Miocene was a critical time for African faunas, because it was during this time that the Afro-Arabian and Eurasian plates came into contact with one another, ending the long isolation of Africa, which, along with rifting in East Africa, created new terrestrial and hydrological connections allowing faunal interchanges. Bukwa is one of only a few African early Miocene localities known that sample fish and, based on these fish, the site probably represents an area of interconnected lakes and large rivers, including floodplains.

New late tertiary fish fossils from the Sinda region, eastern Zaire

1992

抄録: An assemblage of about 200 fish remains, recently collected from late Miocene early Pliocene deposits of the Sinda area, is described. Although the collection is small, several taxa not previously reported from these localities are included. Gymnarchus, Hydrocynus and Bagrus are new for the Sinda-Mogari ichthyofauna, whereas the previously doubtful presence of Clariidae is now confirmed by several finds, including one identifiable as Clarias.

A NEW SEMLIKIICHTHYS FISH (TELEOSTEI, PERCIFORMES) FROM THE UPPER MIOCENE OF CHAD: FOSSIL RECORD AND PALAEOBIOGEOGRAPHICAL IMPLICATIONS

Palaeontology, 2008

Abstract: Semlikiichthys is a fossil genus of perciform fish from the Neogene continental deposits of Africa. Until now, it was known in Mio-Pliocene sites of the Great Lake Region and of the River Nile by a single species, S. rhachirhinchus. Here, we describe new Semlikiichthys material recovered from Central Africa (Upper Miocene of Toros-Menalla, western Djurab, Chad), and compare it to S. rhachirhinchus, which is the only known species of the genus, and also with Lates niloticus, which is the fish in African Neogene deposits that most closely resembles it. We attribute the Chadian material to Semlikiichthys darsao sp. nov., based on ten osteological characters of the neurocranium, the maxilla, the dentary and the first vertebra. Our comparative anatomical study also enables us to provide a revised diagnosis for the genus and to reconsider the taxonomic attribution of the fossils assigned to it. Furthermore, the fossil record of Semlikiichthys supports a connection between sub-basins of the Nilo-Sudanese region during the Miocene, and a disruption between the Great Lake and the Nile Basin on the one hand and the Chadian Basin on the other before 7 Ma.