''Figaro'' 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 ...

shark Sharks are a group of elasmobranch cartilaginous fish characterized by a ribless endoskeleton, dermal denticles, five to seven gill slits on each side, and pectoral fins that are not fused to the head. Modern sharks are classified within the ...

, and part of 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 ...

Pentanchidae Pentanchidae, the deepwater catsharks, is a family of sharks belonging to the order Carcharhiniformes Carcharhiniformes ( from Classical Greek ' (karcharos) 'sharp/jagged' and ' (rhinos) 'nose', plus Latin ''forme'' 'shape'), commonly known a ...

, the deepwater catsharks. Until 2008, ''Figaro'' was generally considered to be a

subgenus In biology, a subgenus ( subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the ge ...

of ''

Galeus ''Galeus'' is a genus of deepwater catshark, belonging to the family (biology), family Pentanchidae, commonly known as sawtail catsharks in reference to a distinctive saw-toothed crest of enlarged dermal denticles, found along the upper edges of ...

'', the sawtail catsharks. The two known species are found off

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

, inhabiting deep, offshore waters on or near the bottom. ''Figaro'' contains small, slender, firm-bodied sharks that bear distinctive crests of enlarged, spiny

dermal denticle A fish scale is a small rigid plate that grows out of the skin of a fish. The skin of most jawed fishes is covered with these protective scale (zoology), scales, which can also provide effective Underwater camouflage, camouflage through the us ...

s along the dorsal and ventral edges of their short

caudal fin 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 ...

s. The

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 ...

is relatively long, such as that the

anal Anal may refer to: Related to the anus *Related to the anus of animals: ** Anal fin, in fish anatomy ** Anal vein, in insect anatomy ** Anal scale, in reptile anatomy *Related to the human anus: ** Anal sex, a type of sexual activity involving ...

and caudal fins are some distance apart. In adult males, the inner margins of the

pelvic fin Pelvic fins or ventral fins are paired fins located on the ventral (belly) surface of fish, and are the lower of the only two sets of paired fins (the other being the laterally positioned pectoral fins). The pelvic fins are homologous to the hi ...

s are fused together to form a subtle "apron" over the

clasper In biology, a clasper is a male anatomical structure found in some groups of animals, used in mating. Male cartilaginous fish have claspers formed from the posterior portion of their pelvic fin which serve to channel semen into the female's ...

s. ''F. boardmani'' is a

predator Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common List of feeding behaviours, feeding behaviours that includes parasitism and micropredation ...

of fishes,

crustacean Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthrop ...

s, and

cephalopod A cephalopod is any member of the molluscan Taxonomic rank, class Cephalopoda (Greek language, Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral symm ...

s, and is

oviparous Oviparous animals are animals that reproduce by depositing fertilized zygotes outside the body (i.e., by laying or spawning) in metabolically independent incubation organs known as eggs, which nurture the embryo into moving offsprings kno ...

; less is known about the ''F. striatus''. Both are harmless and are of no economic importance.

Taxonomy

''Figaro'' was coined as a

of ''Pristiurus'' by Australian

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 ...

Gilbert Percy Whitley Gilbert Percy Whitley (9 June 1903 – 18 July 1975) was a British-born Australian ichthyologist and malacologist who was curator of fishes at the Australian Museum in Sydney for about 40 years. Early life and education Gilbert Percy Whitley ...

in a 1928 issue of the

scientific journal In academic publishing, a scientific journal is a periodical publication designed to further the progress of science by disseminating new research findings to the scientific community. These journals serve as a platform for researchers, schola ...

''Records of the Australian Museum'', to contain his newly described species ''P. boardmani''. In 1908,

Henry Weed Fowler Henry Weed Fowler (March 23, 1878 – June 21, 1965) was an American zoologist born in Holmesburg, Philadelphia, Holmesburg, Pennsylvania. He studied at Stanford University under David Starr Jordan. He joined the Academy of Natural Sciences in Ph ...

synonymized ''Pristiurus'' with the genus ''

''. Though Whitley elevated ''Figaro'' to the rank of full genus in 1939, most authors continued to regard ''Figaro'' as a subgenus of ''Galeus''. In 1983, Yuan-Ting Chu and colleagues referenced ''Figaro'' to contain ''Galeus boardmani'', ''Dichichthys melanobranchus'' (=''

Parmaturus melanobranchus The blackgill catshark or blackgill bristle shark (''Dichichthys melanobranchus'') is a deep water bristle shark known from very few specimens, found on or near the bottom on the continental slope, at off the coasts of China and Japan. Specimen ...

''), and ''F. piceus'' (=''P. melanobranchus''). However, it is uncertain whether they intended to resurrect ''Figaro'' or were simply unaware of its synonymy with ''Galeus'', and their use of the ventral denticle crest to define the genus posed taxonomic problems. In 2008,

Commonwealth Scientific and Industrial Research Organisation The Commonwealth Scientific and Industrial Research Organisation (CSIRO) is an Australian Government agency that is responsible for scientific research and its commercial and industrial applications. CSIRO works with leading organisations arou ...

(CSIRO) researchers Daniel Gledhill, Peter Last, and William White resurrected ''Figaro'' with additional defining characters, to contain ''F. boardmani'' and the new species ''F. striatus''. The genus has since been generally accepted as distinct. One of the key characteristics of ''Figaro'', the ventral crest of denticles on the

, is also present in several species of the genus ''

Parmaturus ''Parmaturus'' is a genus of deepwater catsharks in the Family (biology), family Pentanchidae. Four species were described in 2007 and another in 2019 with more species likely to be described in the near future. Species The following are the cur ...

'', as well as the

Springer's sawtail catshark Springer's sawtail catshark (''Galeus springeri'') is a species of shark belonging to the family Pentanchidae, the deepwater catsharks. This shark is found in waters deep off the islands of the Antilles, from Cuba to the Leewards. A small, slim- ...

(''G. springeri'') and the

mouse catshark The mouse catshark (''Galeus murinus'') is a species of shark belonging to the family Pentanchidae, the deepwater catsharks. It is common in the northeastern Atlantic Ocean from Iceland to Western Sahara. There is much taxonomic confusion regardi ...

(''G. murinus''). ''Figaro'' also closely resembles the genus ''

Asymbolus ''Asymbolus'' is a genus of catsharks in the Family (biology), family Pentanchidae, the deepwater catsharks. Species The currently recognized species in this genus are: * ''Australian spotted catshark, Asymbolus analis'' (James Douglas Ogilby, ...

'' in several morphological characters, including the fusion of the

inner margins in adult males. More research is required to elucidate the relationships between ''Figaro'', ''Galeus'', ''Asymbolus'', and ''Parmaturus''.

Species

* '' Figaro boardmani'' ( Whitley, 1928) (Australian sawtail catshark) * '' Figaro striatus'' Gledhill,

Last A last is a mechanical form shaped like a human foot. It is used by shoemakers and cordwainers in the manufacture and repair of shoes. Lasts come in many styles and sizes, depending on the exact job they are designed for. Common variations ...

& W. T. White, 2008 (northern sawtail catshark)

Distribution and habitat

Both ''Figaro'' species are

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

n waters, ''F. boardmani'' in the south and ''F. striatus'' in the northeast. They are deepwater species found on or near the

sea floor The seabed (also known as the seafloor, sea floor, ocean floor, and ocean bottom) is the bottom of the ocean. All floors of the ocean are known as seabeds. The structure of the seabed of the global ocean is governed by plate tectonics. Most of ...

, inhabiting the outer

continental shelf A continental shelf is a portion of a continent that is submerged under an area of relatively shallow water, known as a shelf sea. Much of these shelves were exposed by drops in sea level during glacial periods. The shelf surrounding an islan ...

and upper

continental slope A continental margin is the outer edge of continental crust abutting oceanic crust under coastal waters. It is one of the three major zones of the ocean floor, the other two being deep-ocean basins and mid-ocean ridges. The continental margi ...

Description

The larger ''Figaro'' species, ''F. boardmani'', reaches long, while the smaller ''F. striatus'' reaches long. Members of this genus closely resemble ''Galeus'', with firm, slender bodies and short heads. The eyes are horizontally oval and equipped with rudimentary

nictitating membrane The nictitating membrane (from Latin '' nictare'', to blink) is a transparent or translucent third eyelid present in some animals that can be drawn across the eye from the medial canthus to protect and moisten it while maintaining vision. Most ...

s (protective third eyelids); a narrow ridge is found beneath each eye and a tiny spiracle behind. The anterior rims of the nostrils are enlarged into triangular flaps. The mouth is wide, with relatively short furrows at the corners, and contains small multi-cusped teeth. There are five pairs of

gill slit Gill slits are individual openings to gills, i.e., multiple gill arches, which lack a single outer cover. Such gills are characteristic of cartilaginous fish such as sharks and rays, as well as deep-branching vertebrates such as lampreys. In c ...

s. The first and second

dorsal fin A dorsal fin is a fin on the back of most marine and freshwater vertebrates. Dorsal fins have evolved independently several times through convergent evolution adapting to marine environments, so the fins are not all homologous. They are found ...

s are similar in size and shape, and are placed mostly behind the

pelvic The pelvis (: pelves or pelvises) is the lower part of an anatomical trunk, between the abdomen and the thighs (sometimes also called pelvic region), together with its embedded skeleton (sometimes also called bony pelvis or pelvic skeleton). ...

and

anal fin 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 o ...

s respectively. The space between the dorsal fins is much longer than the length of either dorsal fin base. 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 ...

s are short and broad, while the pelvic and

s are low with rather long bases. The pectoral, pelvic, and anal fins are proportionally smaller than in ''Galeus''. Unlike ''Galeus'' species, adult males have a slight "apron" formed by the fusion of the pelvic fin inner margins; the apron partially covers the

claspers In biology, a clasper is a male anatomical structure found in some groups of animals, used in mating. Male cartilaginous fish have claspers formed from the posterior portion of their pelvic fin which serve to channel semen into the female's c ...

, which taper towards the tip. The

is long, with the anal and

s well-separated. The caudal fin is short, with a small lower lobe and a ventral notch near the tip of the upper lobe. The body and fins are densely covered by tiny, overlapping

s. In addition, there are enlarged denticles that form prominent saw-like crests on both the dorsal and the ventral edges of the caudal fin. The dorsal coloration consists of dark saddles along the back and tail, which are wider in ''F. boardmani'' and thinner in ''F. striatus''. The two species also differ in various morphometric characters, such as in the relative size of the eye.

Biology and ecology

The natural histories of ''Figaro'' species are poorly known. ''F. boardmani'' feeds mostly on fishes,

s, and

s, and has an

mode of reproduction.

Human interactions

Neither ''Figaro'' species is commercially important or significantly threatened by fishing activity, though ''F. boardmani'' forms a regular component of

bottom trawl Bottom trawling is trawling (towing a trawl, which is a fishing net) along the seafloor. It is also referred to as "dragging". The scientific community divides bottom trawling into benthic trawling and Demersal zone, demersal trawling. Benthic tra ...

bycatch Bycatch (or by-catch), in the fishing industry, is a fish or other marine species that is caught unintentionally while fishing for specific species or sizes of wildlife. Bycatch is either the wrong species, the wrong sex, or is undersized or juve ...

commercial fisheries Commercial fishing is the activity of catching fish and other seafood for commercial profit, mostly from wild fisheries. It provides a large quantity of food to many countries around the world, but those who practice it as an industry must often p ...

within its range. The

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the stat ...

(IUCN) has listed ''F. boardmani'' as

Least Concern A least-concern species is a species that has been evaluated and categorized by the International Union for Conservation of Nature (IUCN) as not being a focus of wildlife conservation because the specific species is still plentiful in the wil ...

and ''F. striatus'' as

Data Deficient A data deficient (DD) species is one which has been categorized by the International Union for Conservation of Nature (IUCN) as offering insufficient information for a proper assessment of conservation status to be made. This does not necessaril ...

. Like other catsharks, ''Figaro'' species pose no danger to humans.

References

{{Taxonbar, from=Q574398 Shark genera Taxa named by Gilbert Percy Whitley Fish described in 1828