Monodactylidae is a family of perciform

bony fish Osteichthyes (), popularly referred to as the bony fish, is a diverse superclass of fish that have skeletons primarily composed of bone tissue. They can be contrasted with the Chondrichthyes, which have skeletons primarily composed of cartilag ...

commonly referred to as monos, moonyfishes or fingerfishes. All are strongly laterally compressed with disc-shaped bodies and tall anal and dorsal fins. Unusually for fish, scales occur on their dorsal fins and sometimes on the

anal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

s. The

pelvic fin Pelvic fins or ventral fins are paired fins located on the ventral surface of fish. The paired pelvic fins are homologous to the hindlimbs of tetrapods. Structure and function Structure In actinopterygians, the pelvic fin consists of two en ...

s are small, sometimes vestigial. They are of moderate size, typically around in length, and ''Monodactylus sebae'' can be taller than it is long, measuring up to 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 two

genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...

, ''Monodactylus'' and ''Schuettea''. They are distributed along the coastlines of Africa, India, and southern Asia, and as far west as Australia. Species of ''Monodactylus'' in particular commonly occur in estuaries. They are truly

euryhaline Euryhaline organisms are able to adapt to a wide range of salinities. An example of a euryhaline fish is the molly (''Poecilia sphenops'') which can live in fresh water, brackish water, or salt water. The green crab (''Carcinus maenas'') is an e ...

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 large shoals. Two extinct species, '' Psettopsis subarcuatus'' and '' Pasaichthys pleuronectiformis'', are known as fossils from the Lutetian lagerstatten of

Monte Bolca Monte Bolca is a lagerstätte near Verona, Italy that was one of the first fossil sites with high quality preservation known to Europeans, and is still an important source of fossils from the Eocene. Geology Monte Bolca was uplifted from the T ...

, Eocene, in Italy.

In aquaria

Aquarists commonly keep ''M. argenteus'' and ''M. sebae'' as pets in domestic aquaria, where they are known as monos or Malayan angels; they are also widely kept in public aquaria. They are hardy and easy to care for, but require brackish water and copious swimming space

External links

* {{Taxonbar, from=Q588431 Monodactylidae, Perciformes families Taxa named by David Starr Jordan Taxa named by Barton Warren Evermann Extant Eocene first appearances