''Nandus'', the Asian leaffishes, is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of small freshwater

ray-finned fishes Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class (biology), class of Osteichthyes, bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built ...

native to southern and southeastern Asia. It is the only member of the family Nandidae, which is classified in the order

Anabantiformes The Anabantiformes , is an Order (biology), order of bony fish (Teleostei) proposed in 2009. They are collectively known as labyrinth fish, are an Order (biology), order of air-breathing freshwater Actinopterygii, ray-finned fish with three sub ...

and closely related to the

Badidae The Badidae, or the chameleonfishes, are a small family (containing about 30 species) of freshwater ray-finned fish in the order Anabantiformes. Their relationship to other members of the order was previously uncertain, with the 5th edition of '' ...

and Pristolepididae. ''

Fishes of the World ''Fishes of the World'' is a standard reference for the systematics of fishes. It was first written in 1976 by the American ichthyologist Joseph S. Nelson (1937–2011). Now in its fifth edition (2016), the work is a comprehensive overview of t ...

'' considered this family and its relatives to be of uncertain taxonomic placement, but more recent taxonomic studies have reaffirmed its anabantiform affinities. Until recently, this family also contained ''

Afronandus The fourspine leaffish (''Afronandus sheljuzhkoi''), is a species of in the Nandidae native to rivers and streams in Ivory Coast and Ghana. Although placed in the family Nandidae by FishBase, most recent authorities place ''Afronandus'' in Poly ...

'' and ''

Polycentropsis the African leaffish (''Polycentropsis abbreviata'') is a species of African leaffish native to fresh waters of western Africa. Although placed in the family Nandidae by FishBase and by the 5th Edition of ''Fishes of the World'' many recent aut ...

'' of tropical

West West 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 Romance langu ...

and

Middle Africa Central Africa ( French: ''Afrique centrale''; Spanish: ''África central''; Portuguese: ''África Central'') is a subregion of the African continent comprising various countries according to different definitions. Middle Africa is an anal ...

. However, genetic studies suggest that these the two African genera actually belong to the South American leaffish family,

Polycentridae Leaffishes are small fishes of the family Polycentridae. They consist of four genera found in fresh and brackish water in South America and Africa. The African species were formerly placed in the family Nandidae (otherwise found only in Asia), b ...

, 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 are 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.

Species

The currently recognized species in this genus are: * '' Nandus andrewi'' H. H. Ng & Jaafar, 2008 * '' Nandus meni''

Hossain Hussein, Hossein, Hussain, Hossain, Huseyn, Husayn, Husein, Hussin, Hoessein, Houcine, Hocine or Husain (; ), coming from the triconsonantal root Ḥ-S-N (), is an Arabic name which is the diminutive of Hassan, meaning "good", "handsome" or " ...

& Sarker, 2013 * '' Nandus mercatus'' H. H. Ng, 2008 * '' Nandus nandus'' ( F. Hamilton, 1822) (Gangetic leaffish) * ''

Nandus nebulosus ''Nandus'', the Asian leaffishes, is a genus of small freshwater Actinopterygii, ray-finned fishes native to southern and southeastern Asia. It is the only member of the family Nandidae, which is classified in the order Anabantiformes and closely ...

'' (

J. E. Gray John Edward Gray (12 February 1800 – 7 March 1875) was a British zoologist. He was the elder brother of zoologist George Robert Gray and son of the pharmacologist and botanist Samuel Frederick Gray (1766–1828). The same is used for a zoo ...

, 1835) (Bornean leaffish) * '' Nandus oxyrhynchus'' H. H. Ng, Vidthayanon & P. K. L. Ng, 1996 * '' Nandus prolixus'' Chakrabarty, Oldfield & H. H. Ng, 2006

References

Nandidae {{Rayfinned-fish-stub Taxa named by Achille Valenciennes