Krøyer's deep sea angler fish (''Ceratias holboelli''), also known as the deep-sea angler, longray seadevil or northern seadevil, is a 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

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 ...

Ceratiidae Ceratiidae, the warty seadevils or caruncled seadevils, are a family of marine ray-finned fishes belonging to the suborder Ceratioidei, the deep-sea anglerfishes, in the anglerfish order Lophiiformes. The warty sea devils are sexually dimorph ...

, the warty seadevils. It is found throughout the oceans of the world, from tropical to polar seas. It is the largest species in its family.

Taxonomy

Krøyer's deep sea angler fish was first formally described in 1845 by the Danish

zoologist Zoology ( , ) is the scientific study of animals. Its studies include the structure, embryology, classification, habits, and distribution of all animals, both living and extinct, and how they interact with their ecosystems. Zoology is one ...

Henrik Nikolai Krøyer Henrik Nikolai Krøyer (22 March 1799 – 14 November 1870) was a Danish zoologist. Born in Copenhagen, he was a brother of the composer Hans Ernst Krøyer. He started studying medicine at the University of Copenhagen in 1817, which he later c ...

with its type locality given as Southern

Greenland Greenland is an autonomous territory in the Danish Realm, Kingdom of Denmark. It is by far the largest geographically of three constituent parts of the kingdom; the other two are metropolitan Denmark and the Faroe Islands. Citizens of Greenlan ...

. When he described ''Ceratias holboelli'' Krøyer also proposed a new

monospecific genus 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 "unispe ...

for his new species, meaning that this species is the

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 ...

of the genus ''

Ceratias ''Ceratias'' is a genus of marine ray-finned fish sometimes referred to as the doublewart- or giant seadevils, belonging to the family Ceratiidae, the warty sea devils. The fishes in this genus are found throughout the world's oceans. Taxonomy ...

'' by

monotypy 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 "unispe ...

. In 1861

Theodore Gill Theodore Nicholas Gill (March 21, 1837 – September 25, 1914) was an American ichthyologist, mammalogist, malacologist, and librarian. Career Born and educated in New York City under private tutors, Gill early showed interest in natural hist ...

proposed the monotypic

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 ...

Ceratiinae of the family Lophiidae. The 5th edition of

Fishes of the World ''Fishes of the World'' is a standard reference for the systematics of fishes. It was first written in 1976 by the American ichthyologist Joseph S. Nelson (1937–2011). Now in its fifth edition (2016), the work is a comprehensive overview of t ...

classifies the family Ceratiidae in the

suborder Order () is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized ...

Ceratioidei Ceratioidei, the deep-sea anglerfishes or pelagic anglerfishes, is a suborder of marine ray-finned fishes, one of five suborders in the order Lophiiformes, the anglerfishes. These fishes are found in tropical and temperate seas throughout the wor ...

of the

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 ...

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

Lophiiformes The anglerfish are ray-finned fish in the order Lophiiformes (). Both the order's common and scientific name comes from the characteristic mode of predation, in which a modified dorsal fin ray acts as a lure for prey (akin to a human angler, ...

Etymology

Krøyer's deep sea angler fish belongs to the genus ''Ceratias'', which means "horn bearer", an allusion to the esca sticking up from the snout. 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 ...

honours the Danish naval officer,

entomologist Entomology (from Ancient Greek ἔντομον (''éntomon''), meaning "insect", and -logy from λόγος (''lógos''), meaning "study") is the branch of zoology that focuses on insects. Those who study entomology are known as entomologists. In ...

and

botanist Botany, also called plant science, is the branch of natural science and biology studying plants, especially Plant anatomy, their anatomy, Plant taxonomy, taxonomy, and Plant ecology, ecology. A botanist or plant scientist is a scientist who s ...

Carl Peter Holbøll Captain Lieutenant Carl Peter Holbøll (1795 – 1856) was a Royal Danish Navy officer, colonial administrator and explorer. Holbøll served as Royal Inspector of Colonies and Whaling in North Greenland (1825–1828), and later as Inspector of S ...

Description

Krøyer's deep sea angler fish is unique within its family in having a single appendage at the tip of its escal bulb. The length of the

illicium ''Illicium'' is a genus of flowering plants treated as part of the family Schisandraceae,

is equivalent to 14.5% to 37.8% of 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 ...

of the fish. The

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 ...

has between 1 and 3 teeth on either side and these are nearly always present in adults with a length of less than but usually absent in larger specimens. The lower part of the bulb of the esca is dark and tapers into the illicium; the upper part is oval with a single appendage. This appendage emerges just in front of the escal pore and is typically a single filament, but may have additional filaments. This species has a maximum published

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 , the largest of the Ceratiidae.

Distribution and habitat

Krøyer's deep sea angler fish has a circumglobal distribution, it is found in the

mesopelagic The mesopelagic zone (Greek language, Greek μέσον, middle), also known as the middle pelagic or twilight zone, is the part of the pelagic zone that lies between the photic epipelagic and the aphotic bathypelagic zones. It is defined by light ...

and

bathypelagic zone The bathypelagic zone or bathyal zone (from Greek βαθύς (bathýs), deep) is the part of the open ocean that extends from a depth of below the ocean surface. It lies between the mesopelagic above and the abyssopelagic below. The bathypela ...

s. It has been found off Brazil in the Western Atlantic. It has also been recorded from southern Tasmania, New Zealand, New South Wales and the

Coral Corals are colonial marine invertebrates within the subphylum Anthozoa of the phylum Cnidaria. They typically form compact Colony (biology), colonies of many identical individual polyp (zoology), polyps. Coral species include the important Coral ...

and

Celebes Sulawesi ( ), also known as Celebes ( ), is an island in Indonesia. One of the four Greater Sunda Islands, and the world's 11th-largest island, it is situated east of Borneo, west of the Maluku Islands, and south of Mindanao and the Sulu Archi ...

seas, the

Bismarck Archipelago The Bismarck Archipelago (, ) is a group of islands off the northeastern coast of New Guinea in the western Pacific Ocean and is part of the Islands Region of Papua New Guinea. Its area is about . History The first inhabitants of the archipela ...

, Solomon Islands, off Taiwan, Japan, in the

Bering Sea The Bering Sea ( , ; rus, Бе́рингово мо́ре, r=Béringovo móre, p=ˈbʲerʲɪnɡəvə ˈmorʲe) is a marginal sea of the Northern Pacific Ocean. It forms, along with the Bering Strait, the divide between the two largest landmasse ...

, the

Aleutian Islands The Aleutian Islands ( ; ; , "land of the Aleuts"; possibly from the Chukchi language, Chukchi ''aliat'', or "island")—also called the Aleut Islands, Aleutic Islands, or, before Alaska Purchase, 1867, the Catherine Archipelago—are a chain ...

, off Oregon and California, the Hawaiian Islands, and east as far as the Peru-Chile Trench in the Pacific. In the Indian Ocean, it has been collected from

Durban Durban ( ; , from meaning "bay, lagoon") is the third-most populous city in South Africa, after Johannesburg and Cape Town, and the largest city in the Provinces of South Africa, province of KwaZulu-Natal. Situated on the east coast of South ...

in South Africa and the

Arabian Sea The Arabian Sea () is a region of sea in the northern Indian Ocean, bounded on the west by the Arabian Peninsula, Gulf of Aden and Guardafui Channel, on the northwest by Gulf of Oman and Iran, on the north by Pakistan, on the east by India, and ...

. This species appear to be absent from the Southern Ocean. In the northeastern Atlantic it is known to occur from Iceland at about 68° N, south to around 8° S in the central Atlantic. This species has been found at depths between but it is most commonly collected between >

Biology

Krøyer's deep sea angler fish shows extreme sexual dimorphism. The metamorphosed females have a maximum

of , while that of males is . The females use the illicium and escal bulb to lure prey. The males possess highly developed sensory organs that they use to find females; once a female is found, the male attaches itself to the female's body as a sexual parasite, eventually becoming incorporated into the female's tissues and blood vessels. The females are

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 ...

and the larvae are

planktonic Plankton are the diverse collection of organisms that drift in water (or air) but are unable to actively propel themselves against currents (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they pro ...

. The spawn is laid in gelatinous rafts and these float to the upper water column and are found from the surface to .

Taxonomy

Etymology

Description

Distribution and habitat

Biology

References

Further reading