Babelichthys

{{Short description|Extinct genus of crestfish}}

{{Speciesbox

| fossil_range = Late Eocene, {{fossil range|38|34|?Priabonian}}

| image = Babelichthys olneyi.png

| image_caption = Part and counterpart slabs.

Scale bar = 20 mm

| taxon = Babelichthys olneyi

| authority = Davesne, 2017

| parent_authority = Davesne, 2017

}}

Babelichthys is an extinct genus of crestfish from the ?Late Eocene-aged{{Cite journal |last=Bannikov |first=A. F. |last2=Erebakan |first2=I. G. |date=2023-10-01 |title=On the Evolution of Some Groups of Marine Bony Fishes in the Cenozoic of the Tethys and Paratethys |url=https://link.springer.com/article/10.1134/S0031030123050015 |journal=Paleontological Journal |language=en |volume=57 |issue=5 |pages=475–490 |doi=10.1134/S0031030123050015 |issn=1555-6174}} Pabdeh Formation of Western Iran. It contains a single species, Babelichthys olneyi.{{Cite journal |last=Davesne |first=Donald |date=2017-06-28 |title=A fossil unicorn crestfish (Teleostei, Lampridiformes, Lophotidae) from the Eocene of Iran |journal=PeerJ |language=en |volume=5 |pages=e3381 |doi=10.7717/peerj.3381 |doi-access=free |issn=2167-8359 |pmc=5493034 |pmid=28674642}} The type specimen was initially figured by Camille Arambourg as a second, poorly-preserved specimen of the co-occurring crestfish Protolophotus, but in 2017 it was identified as its own distinct taxon.{{Cite book |last1=Muséum national d'histoire naturelle (France) |url=https://www.biodiversitylibrary.org/item/281269 |title=Notes et mémoires sur le Moyen-Orient |last2=naturelle (France) |first2=Muséum national d'histoire |date=1966 |publisher=Muséum national d'histoire naturelle |volume=t.8 (1966) |location=Paris}}

The single known specimen consists of a head and the front-most region of the dorsal fin, preserving the extremely elongated and enlarged first dorsal-fin ray. It has been inferred that Babelichthys had a highly elongated "crest" at the front of its dorsal fin that projected horizontally forwards like a horn, akin to that of the extant unicorn crestfish (Eumecichthys fiski) but even larger and more elongated.

It and the unicorn crestfish are each other's closest known relatives. However, some studies find Lophotidae to be paraphyletic, and place Babelichthys as an indeterminate taeniosome.{{Cite journal |last=Brownstein |first=Chase Doran |last2=Near |first2=Thomas J |date=2024-06-01 |title=Evolutionary origins of the lampriform pelagic radiation |url=https://academic.oup.com/zoolinnean/article/201/2/422/7319343 |journal=Zoological Journal of the Linnean Society |volume=201 |issue=2 |pages=422–430 |doi=10.1093/zoolinnean/zlad142 |issn=0024-4082}}

{{Multiple image

| image1 = †Babelichthys olneyi, gen. et sp. nov. holotype MNHN.F.EIP11d (cropped 2).png

| image2 = †Babelichthys olneyi, gen. et sp. nov. holotype MNHN.F.EIP11d (cropped).png

| footer = Scale bar = 10 mm

| total_width = 600

| align = center

}}