Butler's frogfish, Butler's anglerfish or the blackspot anglerfish (''Tathicarpus butleri''), is a rare species of marine

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

belonging to the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

Histiophryninae Histiophryninae, the star-fingered frogfishes, is a subfamily of marine ray-finned fishes belonging to the family Antennariidae, the frogfishes. The species in this family are found in the Indian and Western Pacific Oceans. Taxonomy Histiophryni ...

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 ...

Antennariidae, the frogfishes. The only member of its genus, this species is the most derived member of its family and represents a separate lineage from all other frogfishes, leading to some consideration of it being placed in its own family, the Tathicarpidae, this name being proposed by Pamela B. Hart ''et al'' in 2022. It is found off the southern coast of

New Guinea New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...

, and along the coasts of

Western Australia Western Australia (WA) is the westernmost state of Australia. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to the south, the Northern Territory to the north-east, and South Australia to the south-east. Western Aust ...

to 33° S

latitude In geography, latitude is a geographic coordinate system, geographic coordinate that specifies the north-south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from −90° at t ...

, the

Northern Territory The Northern Territory (abbreviated as NT; known formally as the Northern Territory of Australia and informally as the Territory) is an states and territories of Australia, Australian internal territory in the central and central-northern regi ...

, and

Queensland Queensland ( , commonly abbreviated as Qld) is a States and territories of Australia, state in northeastern Australia, and is the second-largest and third-most populous state in Australia. It is bordered by the Northern Territory, South Austr ...

to 22° S latitude. A

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from the Ancient Greek word (), meaning "the depths". ...

species, it inhabits inshore

tropical The tropics are the regions of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. This is because of Earth's ax ...

waters and

coral reef A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in group ...

s to a maximum depth of , though most are found shallower than .McGrouther, M. (October 2007)
Blackspot Anglerfish
''Australian Museum Fish Site''. Retrieved on March 10, 2009. Its

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

honours its discoverer Dr. A. Graham Butler. This species reaches a maximum length of . It has a stout, laterally compressed body with a large head longer than deep. Like other

anglerfish The anglerfish are ray-finned fish in the order Lophiiformes (). Both the order's common name, common and scientific name comes from the characteristic mode of predation, in which a modified dorsal Fish fin#Ray-fins, fin ray acts as a Aggressiv ...

es, the first dorsal fin ray is modified into a lure for attracting prey. The illicium ("fishing rod") of the Butler's frogfish is very long, measuring 24-47% the

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

, and lacks dermal spines. At the tip is a distinct esca ("fishing lure") that may measure 22% the standard length, consisting of a thin, broad appendage covered with hair-like filaments and bearing 1-2 dark spots at the base. The mouth is protrusible, with many slender, sharp

teeth A tooth (: teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, tear ...

on the

jaw The jaws are a pair of opposable articulated structures at the entrance of the mouth, typically used for grasping and manipulating food. The term ''jaws'' is also broadly applied to the whole of the structures constituting the vault of the mouth ...

vomer The vomer (; ) is one of the unpaired facial bones of the skull. It is located in the midsagittal line, and articulates with the sphenoid, the ethmoid, the left and right palatine bones, and the left and right maxillary bones. The vomer forms ...

, and

palatines Palatines () were the citizens and princes of the Palatinates, Holy Roman States that served as capitals for the Holy Roman Emperor. After the fall of the Holy Roman Empire in 1806, the nationality referred more specifically to residents of the ...

. The

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fus ...

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 are tall, containing 10-11 and 7

fin ray 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 b ...

s respectively; the

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 ...

is long and contains 9 rays. The Butler's frogfish has unusually long and "arm-like"

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 ...

lobes, which unlike other frogfish are largely detached from the sides of the body. Its genus name ''Tathicarpus'', meaning "extending wrist", refers to this trait. The fish uses these pectoral fins to clamber along the sea bottom. The number of pectoral fin rays is reduced (6-7 as opposed to 8 or more in other frogfish), and the Butler's frogfish can move each ray individually like "fingers" to steady itself or to hold on to objects. 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 contain 5 rays each and are placed beneath the body. The skin is densely covered with bifurcate spinules; there are also varying numbers of large, fringed filaments over the head and body. The coloration ranges from pale gray to greenish to brown, with darker markings. The fin membranes are thin and translucent.

References

{{Taxonbar, from=Q654990 Histiophryninae Fish described in 1907