Alepocephaliformes

{{Short description|Order of ray-finned fishes}}

{{Automatic taxobox

| image = Alepocephalus tenebrosus.jpg

| image_caption = California slickhead, Alepocephalus tenebrosus

| taxon = Alepocephaliformes

| authority = Marshall, 1962{{cite journal |author=Thomas J. Near |author2=Christine E. Thacker |title=Phylogenetic Classification of Living and Fossil Ray-Finned Fishes (Actinopterygii) |journal=Bulletin of the Peabody Museum of Natural History |volume=65 |issue=1 |pages=3–302 |doi=10.3374/014.065.0101}}

| display_parents = 2

| subdivision_ranks = Families

| subdivision = See text

| type_species = Alepocephalus rostratus

}}

Alepocephaliformes is an order of marine deep-sea teleost fishes.[https://par.nsf.gov/servlets/purl/10323297 The Emerging Phylogenetic Perspective on the Evolution of Actinopterygian Fishes] It was previously classified as the suborder Alepocephaloidei of the order Argentiniformes.

As an adaptation to a life in the deep-sea, there is no swim bladder, and the ossification of the skeleton is reduced. The largest known member is Narcetes shonanmaruae, the largest deep-sea-endemic bony fish.{{cite journal | pmc=7835233 | date=2021 | last1=Fujiwara | first1=Y. | last2=Kawato | first2=M. | last3=Poulsen | first3=J. Y. | last4=Ida | first4=H. | last5=Chikaraishi | first5=Y. | last6=Ohkouchi | first6=N. | last7=Oguri | first7=K. | last8=Gotoh | first8=S. | last9=Ozawa | first9=G. | last10=Tanaka | first10=S. | last11=Miya | first11=M. | last12=Sado | first12=T. | last13=Kimoto | first13=K. | last14=Toyofuku | first14=T. | last15=Tsuchida | first15=S. | title=Discovery of a colossal slickhead (Alepocephaliformes: Alepocephalidae): An active-swimming top predator in the deep waters of Suruga Bay, Japan | journal=Scientific Reports | volume=11 | issue=1 | page=2490 | doi=10.1038/s41598-020-80203-6 | pmid=33495481 | bibcode=2021NatSR..11.2490F }}{{Cite journal |last1=Fujiwara |first1=Yoshihiro |last2=Tsuchida |first2=Shinji |last3=Kawato |first3=Masaru |last4=Masuda |first4=Kotohiro |last5=Sakaguchi |first5=Sakiko Orui |last6=Sado |first6=Tetsuya |last7=Miya |first7=Masaki |last8=Yoshida |first8=Takao |date=2022-07-01 |title=Detection of the Largest Deep-Sea-Endemic Teleost Fish at Depths of Over 2,000 m Through a Combination of eDNA Metabarcoding and Baited Camera Observations |journal=Frontiers in Marine Science |language=English |volume=9 |doi=10.3389/fmars.2022.945758 |doi-access=free |issn=2296-7745}}