''Nemadactylus'' is a genus of marine ray-finned fish, traditionally regarded as belonging to the family

Cheilodactylidae Cheilodactylidae , commonly called morwongs but also known as butterfish, fingerfins, jackassfish, sea carp, snappers, and moki, is a family of marine ray-finned fish. They are found in subtropical oceans in the Southern Hemisphere. The common ...

, the members of which are commonly known as morwongs. They are found in the South Atlantic, Indian and South Pacific Oceans.

Systematics

''Nemadactylus'' was first formally described as a genus in 1839 by the

Scottish Scottish usually refers to something of, from, or related to Scotland, including: *Scottish Gaelic, a Celtic Goidelic language of the Indo-European language family native to Scotland *Scottish English *Scottish national identity, the Scottish ide ...

naval surgeon,

arctic explorer Arctic exploration is the physical exploration of the Arctic region of the Earth. It refers to the historical period during which mankind has explored the region north of the Arctic Circle. Historical records suggest that humankind have explored ...

and naturalist Sir John Richardson when he described ''Nemadactylus concinnus'' which he designated the type species of the new genus by monotypy. ''Nemadactylus concinnus'' is now considered to be a

synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are all ...

of Johann Reinhold Forster's '' Chichla macroptera''. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

is a compound of ''nema'' meaning "thread" and ''dactylus'' which means "finger", a referenve to the long rays of the pectoral fins of the type species. The genus has traditionally been assigned to Cheilodactylidae, but a number of papers published in the late 1990s and early 2000s placed ''Nemadactylus'' as sister to ''

Latris Latris may refer to: * ''Latris'', a Greek word meaning "slave Slavery and enslavement are both the state and the condition of being a slave—someone forbidden to quit one's service for an enslaver, and who is treated by the enslaver a ...

'', suggesting its reassignment to the

Latridae Latridae commonly called trumpeters, is a family of marine ray-finned fish. They are found in temperate seas in the Southern Hemisphere. The classification of the species within the Latridae and the related Cheilodactylidae is unclear.They a ...

. Further genetic and morphological analyses strongly support the placement of ''Nemadactylus'' in the family

, alongside almost all of the other species formerly classified in the Cheilodactylidae. Only two Southern African species, ''

Cheilodactylus fasciatus The redfingers (''Cheilodactylus fasciatus'') is a species of marine ray-finned fish, belonging to the family Cheilodactylidae, commonly referred to as morwongs. It is found only off the coasts of Namibia and South Africa, in rock pools and from ...

'' and '' C. pixi'' would remain in the revised Cheilodactylidae. The 5th edition of

Fishes of the World ''Fishes of the World'' by the American ichthyologist Joseph S. Nelson (1937–2011) is a standard reference for fish systematics. Now in its fifth edition (2016), the work is a comprehensive overview of the diversity and classification of the ...

, however, retains ''Nemadactylus'' within the family Cheiloactylidae.

Species

There are currently seven recognized species in this genus: * ''

Nemadactylus bergi ''Nemadactylus'' is a genus of marine ray-finned fish, traditionally regarded as belonging to the family Cheilodactylidae, the members of which are commonly known as morwongs. They are found in the South Atlantic, Indian and South Pacific Oceans. ...

'' ( Norman, 1937) (Castaneta) * ''

Nemadactylus douglasii The porae (''Nemadactylus douglasii''), the grey morwong, blue morwong, butterfish, Douglas' morwong, Eastern blue morwong, great perch, queen snapper, rubberlip morwong or silver morwong, is a species of marine ray-finned fish, traditionally reg ...

'' ( Hector, 1875) (Porae) * ''

Nemadactylus gayi ''Nemadactylus'' is a genus of marine ray-finned fish, traditionally regarded as belonging to the family Cheilodactylidae, the members of which are commonly known as morwongs. They are found in the South Atlantic, Indian and South Pacific Oceans. ...

'' ( Kner, 1865) * ''

Nemadactylus macropterus ''Nemadactylus macropterus'', the tarakihi, jackass morwong or deep sea perch, is a species of marine ray-finned fish, traditionally regarded as belonging to the family Cheilodactylidae, the members of which are commonly known as morwongs. It is ...

'' ( J. R. Forster, 1801) (Tarakihi) * ''

Nemadactylus monodactylus St. Paul's fingerfin (''Nemadactylus monodactylus''), is a species of marine ray-finned fish, traditionally regarded as belonging to the family Cheilodactylidae, the members of which are commonly known as morwongs. It is native to the southwester ...

'' ( Carmichael, 1819) (St. Paul's fingerfin) * ''

Nemadactylus valenciennesi ''Nemadactylus valenciennesi'' (common names include blue morwong, queen snapper, the queen fish, sea carp or southern blue morwong), is a species of marine ray-finned fish, traditionally regarded as belonging to the family Cheilodactylidae, t ...

'' ( Whitley, 1937) (Sea carp) * '' Nemadactylus vemae'' ( M. J. Penrith, 1967) An eighth undescribed species informally, named the "king tarakihi", is known from the Tasman Sea off New South Wales and New Zealand as well as at Lord Howe Island,

Norfolk Island Norfolk Island (, ; Norfuk: ''Norf'k Ailen'') is an external territory of Australia located in the Pacific Ocean between New Zealand and New Caledonia, directly east of Australia's Evans Head and about from Lord Howe Island. Together with ...

and the Kermadec Islands, this has been given the placeholder name ''Nemadactylus sp'', as it has not been formally described so no binomial has been applied. This undescribed species differs in morphology from ''N. macropterus''. Studies in New Zealand have confirmed that the "king tarahiki" is genetically separate from ''N. macropterus'' and a phylogenetic study found that the undescribed ''N. sp'' is a sister taxon to the eastern Pacific ''N. gayi''.

Characteristics

''Nemadactylus'' morwongs are separated from related taxa by having an ova; compressed body with a shallow dorsal profile to the head. There is a continuous dorsal fin with no incision separating the spiny part from the soft rayed part. The dorsal fin has 16-18 spines and 24-31 soft rays, the spines are not elongated. 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 ...

has 3 spines and 11-19 soft rays while the pectoral fin has 16-16 rays, one of which is highly elongated, reaching beyond the origin of the anal fin. They vary in total length from in ''N. bergi'' to in ''N. valenciennesi''.

Distribution, habitat and biology

''Nemadactylus'' morwongs are found in the temperate regions of the southern hemisphere off southern Africa, the southern Indian Ocean, Australia, New Zealand and southern South America. They are predators of benthic invertebrates.

Fisheries

''Nemadactylus'' morwongs, partricularly the larger species, are of some interest to fisheries. For example the tarakihi (''N. macropterus'') is sought after by both commercial and recreation fisheries in New Zealand.

References

{{Taxonbar, from=Q2135383 Latridae Cheilodactylidae Taxa named by John Richardson (naturalist)