| Monodactylidae Temporal range: Eocene to Recent | |
|---|---|
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| Silver moony,Monodactylus argenteus | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Acanthuriformes |
| Family: | Monodactylidae D. S. Jordan &Evermann, 1898 |
| Genera | |
Monodactylidae is a family ofperciformbony fish commonly referred to asmonos,moonyfishes orfingerfishes. All are strongly laterally compressed with disc-shaped bodies and tall anal anddorsal fins. Unusually for fish,scales occur on their dorsal fins and sometimes on theanal fins. Thepelvic fins are small, sometimesvestigial. They are of moderate size, typically around 25 centimetres (9.8 in) in length, andMonodactylus sebae can be taller than it is long, measuring up to 30 centimetres (12 in) from the tip of the dorsal fin down to the tip of the anal fin. These long, scaly fins have given them the name "fingerfishes". Most are silvery with yellow and black markings; the juveniles are especially attractive, and most species are popular as aquarium fish.
The family contains six extant species in twogenera,Monodactylus andSchuettea. They are distributed along the coastlines of Africa, India, and southern Asia, and as far west as Australia. Species ofMonodactylus in particular commonly occur in estuaries. They are trulyeuryhaline and can live in fresh water for extended periods. Moonyfishes are predators and feed primarily on smaller fish and invertebrates. They are found primarily in shallow water and form largeshoals.
Two extinct species,Psettopsis subarcuatus andPasaichthys pleuronectiformis, are known as fossils from theLutetianlagerstatten ofMonte Bolca,Eocene, inItaly.
Aquarists commonly keepM. argenteus andM. sebae as pets in domesticaquaria, where they are known asmonos orMalayan angels; they are also widely kept inpublic aquaria. They are hardy and easy to care for, but requirebrackish water and copious swimming space.[1].