''Balistoides'' 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 marine

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 ...

belonging to the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Balistidae, the triggerfishes. The

triggerfish Triggerfish are about 40 species of often brightly colored marine ray-finned fishes belonging to the family Balistidae. Often marked by lines and spots, they inhabit tropical and subtropical oceans throughout the world, with the greatest speci ...

es in this genus are found in the

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

region.

Taxonomy

''Balistoides'' was first proposed as a genus in 1935 by the English

ichthyologist Ichthyology is the branch of zoology devoted to the study of fish, including bony fish (Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). According to FishBase, 35,800 species of fish had been described as of March 2 ...

Alec Fraser-Brunner Alec Frederick Fraser-Brunner (6 April 1906 – 17 Sept 1986) was a British ichthyologist. His career included work with the Colonial Office, the Food and Agriculture Organization, and as the curator of the Van Kleef Aquarium in Singapore and the ...

with ''Balistes viridescens'' designated as its

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

. ''B. viridescens'' had originally been described in 1801 by the German naturalists

Marcus Elieser Bloch Marcus Elieser Bloch (1723–1799) was a German physician and naturalist who is best known for his contribution to ichthyology through his multi-volume catalog of plates illustrating the fishes of the world. Brought up in a Hebrew-speaking Jewish ...

and

Johann Gottlob Schneider Johann Gottlob Theaenus Schneider (18 January 1750 – 12 January 1822) was a German classicist and naturalist. Biography Schneider was born at Collm in Saxony. In 1774, on the recommendation of Christian Gottlob Heine, he became secretary to ...

with its type locality not given. Nevertheless, its type locality is Mauritius, as the description was based on

Bernard Germain de Lacépède Bernard-Germain-Étienne de La Ville-sur-Illon, comte de Lacépède or La Cépède (; 26 December 17566 October 1825) was a French natural history, naturalist and an active freemason. He is known for his contribution to the Comte de Buffon's g ...

's ''Baliste verdatre''. A 2016 study found that ''Balistoides'' was not

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

with ''B. conspiciillum'' being

sister A sister is a woman or a girl who shares parents or a parent with another individual; a female sibling. The male counterpart is a brother. Although the term typically refers to a familial relationship, it is sometimes used endearingly to ref ...

to '' Balistapus'' , with ''

Melichthys ''Melichthys'' is a small genus in the triggerfish family ( Balistidae). Member species are found in the Indian Ocean, Pacific Ocean and even the Red Sea The Red Sea is a sea inlet of the Indian Ocean, lying between Africa and Asia. Its c ...

'' being its next closest relative, while ''B. viridescens'' was recovered as sister to '' Pseudobalistes''. However, the 2016 study stated that the results concerning the "close association" of ''Balistapus undulatus'' and ''Balistoides conspicillum'' were only "moderately supported", and it has not resulted in the classification of the triggerfishes being changed.

Etymology

''Balistoides'' sufffixes ''-oides'' onto ''Balistes'' and means "having the form of ''Balistes''".

Species

''Balistoides'' contains 2 currently recognised species:

Characteristics

''Balistoides'' triggerfishes have a laterally compressed

caudal peduncle Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only ...

. The scales above the base of the

pectoral fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish aquatic locomotion, swim. Apart from the tail or caudal fin, fish fins have no direct connection with the vertebral column ...

and the gill slit are very enlarged and form a flexible tympanum. There is an obvious groove on the snout in front of the eye. The teeth in the jaw are white and do not prominently project. Almost all of the cheek is covered with scales except for a very small fold at the corner of the mouth. The dorsal and ventral profiles of the head are concave, straight or slightly convex. The body is not plain black or very dark blue but is marked with different-coloured blotches and lines. ''B. viridescens'' has a maximum

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

of , while the maximum published total length of ''B. conspicillum'' is .

Distribution and habitat

''Balistoides'' triggerfishes are found in the Indian and Western Pacific Oceans from the eastern coast of Africa east as far as the

Tuamotus The Tuamotu Archipelago or the Tuamotu Islands (, officially ) are a French Polynesian chain of just under 80 islands and atolls in the southern Pacific Ocean. They constitute the largest chain of atolls in the world, extending (from northwest to ...

and

Line Islands The Line Islands, Teraina Islands or Equatorial Islands () are a chain of 11 atolls (with partly or fully enclosed lagoons, except Vostok and Jarvis) and coral islands (with a surrounding reef) in the central Pacific Ocean, south of the Hawa ...

, south to northern Australia and north to southern Japan. The two species in this genus are associated with coral reefs, at depths down to .

References

{{Taxonbar, from=Q2727049 Balistidae Marine fish genera Taxa named by Alec Fraser-Brunner