Nandidae, the leaffish, are a

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

of small freshwater fishes which some authorities classify in the order

Anabantiformes The Anabantiformes , collectively known as Labyrinth fish. are an Order (biology), order of air-breathing freshwater Actinopterygii, ray-finned fish with two suborders, five Family (biology), families (Snakehead (fish), Channidae, Aenigmachanna ...

, but which the 5th edition of '' Fishes of the World'' classifies the family and the related Badidae and Pristolepididae outside that order as "sister-taxa". Fishes of the World classified these families and the Anabantiformes alongside Synbranchiformes,

Carangiformes Carangiformes is an order of the ray-finned fishes. The order is part of a clade which is a sister clade to the Ovalentaria, the other orders in the clade being Synbranchiformes, Anabantiformes, Istiophoriformes and Pleuronectiformes. The Caran ...

Istiophoriformes Istiophoriformes are an order of bony fish which is not fully recognized by some taxonomists, with some including the two extant families Xiphiidae and Istiophoridae, and others including the family Sphyraenidae. Families The following famil ...

and

Pleuronectiformes A flatfish is a member of the ray-finned demersal fish order Pleuronectiformes, also called the Heterosomata, sometimes classified as a suborder of Perciformes. In many species, both eyes lie on one side of the head, one or the other migrating ...

in a monophyletic clade which is a sister taxon to the

Ovalentaria Ovalentaria is a clade of ray-finned fishes within the Percomorpha, referred to as a subseries. It is made up of a group of fish families which are referred to in ''Fishes of the World's'' fifth edition as'' incertae sedis'', as well as the orde ...

but to which the authors do not assign a rank or a name. According to FishBase, the family includes three genera: '' Nandus'' of South and

Southeast Asia Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical south-eastern region of Asia, consisting of the regions that are situated south of mainlan ...

with several species, and the

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...

'' Afronandus'' and '' Polycentropsis'' of tropical

West West or Occident is one of the four cardinal directions or points of the compass. It is the opposite direction from east and is the direction in which the Sun sets on the Earth. Etymology The word "west" is a Germanic word passed into some ...

and

Middle Africa Central Africa is a subregion of the African continent comprising various countries according to different definitions. Angola, Burundi, the Central African Republic, Chad, the Democratic Republic of the Congo, the Republic of the Congo, Eq ...

. Most recent authorities place the two African genera in the South American leaffish family,

Polycentridae Leaffishes are small fishes of the family Polycentridae. According to FishBase, it only includes the genera '' Monocirrhus'' and '' Polycentrus'' from fresh and brackish water in tropical South America. Although included in the Asian leaffish fa ...

, which is only distantly related to ''Nandus'' (the "true" Nandidae).Collins, R.A., R. Britz, and L. Ruber (2015). Phylogenetic systematics of leaffishes (Teleostei: Polycentridae, Nandidae). J Zoolog Syst Evol Res 53(4). Another Asian family, Pristolepididae, share the common name leaffish and appear to be more closely related. These fish usually have a coloration that appears to have evolved to resemble dead leaves, and very large protractile mouths. Those features, along with their peculiar movements (seemingly intended to resemble a leaf innocently moving through the water) help them to catch fairly large prey compared to their body size, including small fish, aquatic insects, and other invertebrates. They tend to stay in one place and wait for prey; they are "lie-in-wait" predators. Their odd, leaf-like appearance and unusual behavior make them interesting to aquarium hobbyists.

Genera

There are three genera in the family: * '' Afronandus'' Meinken, 1955 * '' Nandus''

Valenciennes Valenciennes (, also , , ; nl, label=also Dutch, Valencijn; pcd, Valincyinnes or ; la, Valentianae) is a commune in the Nord department, Hauts-de-France, France. It lies on the Scheldt () river. Although the city and region experienced a ...

, 1831 * '' Polycentropsis'' Boulenger, 1901

References

{{Rayfinned-fish-stub

Genera

See also

References