Hiodontiformes
Hiodon tergisus
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Cohort:	Osteoglossomorpha
Order:	Hiodontiformes Taverne, 1979
Type species
Hiodon tergisus (Lesueur, 1818)
Families[1][2]
Hiodontidae (mooneyes)

Hiodontiformes /haɪəˈdɒntɪfɔːrmiːz/ is an order of ray-finned fish consisting of the two living species of the mooneye family, Hiodontidae, and three extinct genera.

These are traditionally classified within the order Osteoglossiformes, a placement some authorities still follow. Fossil study of the extinct genus Yanbiania suggests that the hiodontids separated from other osteoglossomorphs early and thus may deserve a separate order.^{[citation needed]}

Taxonomy

• Order Hiodontiformes McAllister 1968 sensu Taverne 1979
  • Genus †Chetungichthys Chang & Chou 1977
    • †Chetungichthys brevicephalus Chang & Chou 1977
    • †Chetungichthys dalinghensis Su 1991
  • Genus †Yanbiania Li 1987
    • †Yanbiania wangqingica Li 1987
  • Genus †Plesiolycoptera Zhang & Zhou 1976
    • †Plesiolycoptera daqingensis Zhang & Zhou 1976
    • †Plesiolycoptera parvus ((Sytchevskaya, 1986) (syn Eohiodon (Gobihiodon) parvus Sytchevskaya, 1986)
  • Family Hiodontidae (mooneyes) Valenciennes 1846 sensu stricto
    • Genus Hiodon Lesueur 1818 [(syn: Amphiodon Rafinesque 1819 non Huber 1909; Hiodon (Amphiodon) (Rafinesque 1819); Hiodon (Clodalus) Rafinesque 1820; Clodalus (Rafinesque 1820); Hiodon (Elattonistius) Gill & Jordan ex Jordan 1877; Elattonistius (Gill & Jordan ex Jordan 1877); Glossodon Rafinesque 1818 non Heckel 1843; Eohiodon Cavender 1966)
      • Hiodon alosoides (goldeye) (Rafinesque 1819)
      • †Hiodon consteniorum Li & Wilson 1994
      • †Hiodon falcatus (Grande, 1979) (syn Eohiodon falcatus (Grande, 1979))
      • †Hiodon rosei (Hussakof 1916) (syn Eohiodon rosei (Hussakof 1916); Leucisus rosei Hussakof, 1916)
      • Hiodon tergisus (mooneye) Lesueur 1818
      • †Hiodon woodruffi Wilson, 1978
      • †Hiodon shuyangensis Shen 1989 (nom dubium, possibly an immature Phareodus)