A fossil unicorn crestfish (Teleostei, Lampridiformes, Lophotidae) from the Eocene of Iran

Abstract

Lophotidae, or crestfishes, is a family of rare deep-sea teleosts characterised by an enlarged horn-like crest on the forehead. They are poorly represented in the fossil record, by only three described taxa. One specimen attributed to Lophotidae has been described from the pelagic fauna of the middle-late Eocene Zagros Basin, Iran. Originally considered as a specimen of the fossil lophotid †Protolophotus, it is proposed hereby as a new genus and species †Babelichthys olneyi, gen. et sp. nov., differs from the other fossil lophotids by its relatively long and strongly projecting crest, suggesting a close relationship with the modern unicorn crestfish, Eumecichthys. This new taxon increases the diversity of the deep-sea teleost fauna to which it belongs, improving our understanding of the taxonomic composition of the early Cenozoic mesopelagic ecosystems.

Offshore marine actinopterygian assemblages from the Maastrichtian–Paleogene of the Pindos Unit in Eurytania, Greece

“…The global Paleocene fossil record is even poorer than that of the Maastrichtian, both in terms of number of known sites, but also in terms of recorded biodiversity and, in most cases, quality of preservation ( Patterson, 1964 ; Thomas et al, 1999 ; Cavin, 2002 ; Friedman & Johnson, 2005 ; Parris, Smith-Grandstaff & Gallagher, 2007 ; Schwarzhans & Milàn, 2017 ; Capobianco, Foreman & Friedman, 2019 ). The Danian neritic sites near Palenque, Mexico, constitute notable exceptions from this rule ( Alvarado-Ortega et al, 2015 ; Cantalice & Alvarado-Ortega, 2016 ; Cantalice, Alvarado-Ortega & Bellwood, 2020 ), yielding well-preserved and diverse shallow water actinopterygian assemblages comprising typical Paleogene (e.g., marine osteoglossomorphs) as well as derived faunal elements (including aulostomoids, pomacentrids and other percomorphs), which foreshadow the more modern-like, acanthomorph-dominated assemblages from the early Eocene of Turkmenistan and the Kabardino-Balkaria ( Bannikov & Parin, 1997 ; Bannikov & Carnevale, 2012 ; Bannikov et al, 2017 ), Bolca, the London Clay and other localities ( Arambourg, 1967 ; Daniltshenko, 1962 ; Eastman & Grande, 1991 ; Bannikov, 1993 ; Bonde, 1997 ; Afsari et al, 2014 ; Davesne, 2017 ; Beckett et al, 2018 ; Friedman & Carnevale, 2018 ).…”

Three-dimensional anatomy of the early EoceneWhitephippus(Teleostei: Lampriformes) documents parallel conquests of the pelagic environment by multiple teleost lineages

“…Bolca also yields two taxa historically described as lampriforms: the enigmatic ‘ Pegasus ’ (Carnevale et al, 2014; Carnevale & Bannikov, 2018) and † Bajaichthys (Bannikov, 2014; Sorbini & Bottura, 1988), the latter now regarded as a morphologically distinctive zeiform (Davesne et al, 2017). The Paleogene lampriform fossil record includes a variety of taeniosomes, all assigned to Lophotidae: † Eolophotes from the Lutetian of Georgia (Daniltshenko, 1980), † Protolophotus and † Babelichthys from the late Eocene of Iran (Arambourg, 1943; Davesne, 2017; Walters, 1957) and † Oligolophotes from the early Oligocene of Russia (Bannikov, 1999). These Russian deposits also yield the incertae sedis deep-bodied genera † Analectis and † Natgeosocus (Bannikov, 2014; Daniltshenko, 1980), with strata of comparable age in Germany yielding the veliferid † Oechsleria (Micklich & Bannikov, 2023).…”

Distribution of the Order Lampriformes in the Mediterranean Sea with Notes on Their Biology, Morphology, and Taxonomy

“…Different phylogenetic surveys conducted with morphological and molecular approaches have placed the Lampriformes order within the Acanthomorpha clade [ 81 , 82 ]. Lampriform fishes are primitive compared to the Percomorpha, but their precise placement among basal Acanthomorpha remains undetermined [ 51 ].…”

“…During archaeological research in the Mediterranean area, some skeletal evidence of about another ten extinct Acanthomorpha species have been found in fossil findings [ 14 , 84 , 85 ]. These fossil relics have been related to ancestral Lampriformes [ 14 , 81 , 85 , 86 ]. In 1999, Sorbini and Sorbini described a fossil of the oldest known lampriform fish, Nardovelifer altipinnis , found in the Cretaceous deposits of Nardò, Italy [ 62 ].…”