The striped boarfish (''Evistias acutirostris''), also known as whiskered boarfish, Japanese boarfish, sailfin armourhead or whiskered armorhead, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of marine

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fishes, is a class of bony fish. They comprise over 50% of living vertebrate species. The ray-finned fishes are so called because their fins are webs of skin supported by bony or hor ...

, an

armourhead Pentacerotidae or armourheads are a small Family (biology), family of fishes in the order Perciformes. They are native to the Indian Ocean, western and central Pacific, and southwestern Atlantic. They are generally found at rocky reefs below nor ...

om the

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

Pentacerotidae Pentacerotidae or armourheads are a small family of fishes in the order Perciformes. They are native to the Indian Ocean, western and central Pacific, and southwestern Atlantic. They are generally found at rocky reefs below normal scuba diving d ...

, which is native to the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...

from the

Hawaiian Islands The Hawaiian Islands ( haw, Nā Mokupuni o Hawai‘i) are an archipelago of eight major islands, several atolls, and numerous smaller islets in the North Pacific Ocean, extending some from the island of Hawaii in the south to northernmost Kur ...

westward to the coast of

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an area ...

and

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

. This is a

reef A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes— deposition of sand, wave erosion planing down rock out ...

-dwelling fish found at depths between . It can reach a

total length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish ...

of . It is currently the only known member of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

''Evistias''.

Description

The striped boarfish has a very deep body which is steep behind the head and rounded underneath the soft part of the dorsal fin. It has an elongated snout which is sturdy in adults and has dense whisker like structures referred to a ''villi'' on the lips and chin, the ones on chin being very long and sometimes branched. The

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through conv ...

is tall and sail-like, contains 4 or 5 stout spines and 26-28 soft rays and has a convex margin towards the rear. The spines get longer from the front to the back but the front soft rays are longer still than the rear spines. 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 3-4 spines and 11-14 soft rays. There are five wide dark stripes on the body, and the dorsal, anal and

caudal 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 are yellow. This species attains a maximum

of .

Distribution

The striped boarfish is found in the Pacific Ocean and has been recorded from

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...

, Japan, New Zealand, the

Kermadec Islands The Kermadec Islands ( mi, Rangitāhua) are a subtropical island arc in the South Pacific Ocean northeast of New Zealand's North Island, and a similar distance southwest of Tonga. The islands are part of New Zealand. They are in total are ...

Lord Howe Island Lord Howe Island (; formerly Lord Howe's Island) is an irregularly crescent-shaped volcanic remnant in the Tasman Sea between Australia and New Zealand, part of the Australian state of New South Wales. It lies directly east of mainland P ...

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 eastern cost of Australia. It has also been recorded at

Easter Island Easter Island ( rap, Rapa Nui; es, Isla de Pascua) is an island and special territory of Chile in the southeastern Pacific Ocean, at the southeasternmost point of the Polynesian Triangle in Oceania. The island is most famous for its nearl ...

Habitat and biology

The striped boarfish is found in coral and rocky reefs, frequently occurring in pairs. It prefers deeper reefs, and is often found near deep rocky drop-offs or over areas of sand substrate at depths of . This is a carnivorous species which has been recorded feeding on

brittlestar Brittlestar is the stage name of Stewart Reynolds, a Stratford, Ontario based comedian, writer, communications consultant, and online television show host. His campaign for KFC Canada was the world's most watched branded video on Facebook in th ...

s off Hawaii. They feed at night.

Taxonomy

The striped boarfish is the only species in the

monospecific 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 "unispec ...

genus ''Evistias'' and was first formally described as ''Histiopterus acutirostris'' in 1844 by Coenraad Jacob Temminck and Hermann Schlegel with the type locality given as Ōmura near

Nagasaki is the capital and the largest city of Nagasaki Prefecture on the island of Kyushu in Japan. It became the sole port used for trade with the Portuguese and Dutch during the 16th through 19th centuries. The Hidden Christian Sites in the ...

Kyūshū is the third-largest island of Japan's five main islands and the most southerly of the four largest islands ( i.e. excluding Okinawa). In the past, it has been known as , and . The historical regional name referred to Kyushu and its surround ...

. David Starr Jordan placed it in the monotypic genus ''Evistias'' in 1907.

References

{{Taxonbar, from=Q5235337 Pentacerotidae Fish of Hawaii