The triplewart seadevil (''Cryptopsaras couesii'') 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 sea devils, and the order

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, ...

. This species is the only member of its

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 ...

. Like other Ceratioids, this species is notable for its extreme

sexual dimorphism Sexual dimorphism is the condition where sexes of the same species exhibit different Morphology (biology), morphological characteristics, including characteristics not directly involved in reproduction. The condition occurs in most dioecy, di ...

Taxonomy

The triplewart seadevil was first formally described in 1883 by the American

biologist A biologist is a scientist who conducts research in biology. Biologists are interested in studying life on Earth, whether it is an individual Cell (biology), cell, a multicellular organism, or a Community (ecology), community of Biological inter ...

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 ...

with its type locality given as off

New York New York most commonly refers to: * New York (state), a state in the northeastern United States * New York City, the most populous city in the United States, located in the state of New York New York may also refer to: Places United Kingdom * ...

in the western North Atlantic at 39°18'30"N, 68°24'00"W,

Albatross Albatrosses, of the biological family Diomedeidae, are large seabirds related to the procellariids, storm petrels, and diving petrels in the order Procellariiformes (the tubenoses). They range widely in the Southern Ocean and the North Paci ...

station 2101, from a depth of . When Gill described this species he classified it in the 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 ...

''Cryptopsaras''. ''Cryptopsaras'' is one of two genera which 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 as belonging to 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.l

Etymology

The triplewart seadevil is the only species in the genus ''Cryptopsaras'', this name is a combination of ''kryptos'', which means "hidden" or "secret", with ''psarus'', meaning "fisherman", an allusion to the very small

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

being almost completely concealed within the tissue of the esca. 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 ...

honors the "eminent"

ornithologist Ornithology, from Ancient Greek ὄρνις (''órnis''), meaning "bird", and -logy from λόγος (''lógos''), meaning "study", is a branch of zoology dedicated to the study of birds. Several aspects of ornithology differ from related discip ...

Elliott Coues Elliott Ladd Coues (; September 9, 1842 – December 25, 1899) was an American army surgeon, historian, ornithologist, and author. He led surveys of the Arizona Territory, and later as secretary of the United States Geological and Geographi ...

Distribution

Triplewart seadevils are ceratioids commonly found worldwide in all major oceans. They are seen in depths ranging from 75 to 4000 m (250 to 13,100 ft), with the majority of specimens found in the mesopelagic and bathypelagic zones between 500 and 1250 m (1600 to 4100 ft). It is dispersed from the deep ocean to shallower water because its weak swimming power allows it to be carried over long distances by ocean currents.

Morphology

Female triplewart seadevils have a laterally compressed, elongated body with a large head and a mouth that is nearly vertical when closed. It has 2 to 3 rows of irregular depressible teeth, with significantly larger teeth on the lower jaw than the smaller upper jaw. The body is covered by deeply embedded hollow spines. Only the tips show and there are no conical bone plates. The 3 lateral caruncles have club-shaped glands that secrete a slime containing luminous granules. Adult females have jet-black pigmentation while juveniles are dark brown. The triplewart seadevil uses an

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

, a sort of spine on the snout, to lure prey. This apparatus is primarily composed of a terminating esca or lure supported by an extremely long

pterygiophore 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 biology, marine environments, so the fins are not all Homology (biol ...

bone encased in a dermal sheath. Winding muscles control the anterior and posterior movement of the bone, suggesting extension and retraction by rotation. Furthermore the illicium has a wide range of

anterior Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position pro ...

and posterior motion. The terminal esca contains

bioluminescent Bioluminescence is the emission of light during a chemiluminescence reaction by living organisms. Bioluminescence occurs in multifarious organisms ranging from marine vertebrates and invertebrates, as well as in some fungi, microorganisms inc ...

bacterial

symbionts Symbiosis (Ancient Greek : living with, companionship < : together; and ''bíōsis'': living) is any type of a close and long-term

; ranging from for females and for males. Typical of Ceratioids, the dwarfed males parasitize the larger females; their specialized jaw has an anterior pair of denticular teeth that are longer than their posterior pair. Males permanently attach themselves to the females, typically the

ventrum The abdomen (colloquially called the gut, belly, tummy, midriff, tucky, or stomach) is the front part of the torso between the thorax (chest) and pelvis in humans and in other vertebrates. The area occupied by the abdomen is called the abdominal ...

but can be almost anywhere on her body, with the specialized denticular apparatus meant for grasping their mate. Once attached, tissue fusion occurs, permanently binding the mouth and one side of the male to the surface of the female. After attachment, the male becomes dependent on the female for blood-circulated nutrients due to the fusion of the circulatory and digestive systems. This case of extreme sexual dimorphism is favored by

natural selection Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the Heredity, heritable traits characteristic of a population over generation ...

due to the random dispersal of individuals. If one of the relatively numerous males is fortunate enough to encounter a female, it attaches for the remainder of its life. This significantly increases the chance of reproduction for the individual and therefore increases its fitness.

Reproduction

Cryptopsaras couesii triplewart seadevil

Female triplewart seadevils are receptive to parasitic males at a young age. Once past

metamorphosis Metamorphosis is a biological process by which an animal physically develops including birth transformation or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and different ...

, sexual parasitism may occur at almost any size and is thought to occur at less than 12 months of age. Despite this, the percentage of reproducing individuals is small. Of 600 metamorphosed females studied, only 6.2% were parasitized. Spawning events occur more than once a year, and the Atlantic Ocean contains triplewart seadevil larvae for most of the year, with summer having the greatest occurrences. The seadevil's method of sexual parasitism leads to the female to be akin to a self-fertilizing

hermaphrodite A hermaphrodite () is a sexually reproducing organism that produces both male and female gametes. Animal species in which individuals are either male or female are gonochoric, which is the opposite of hermaphroditic. The individuals of many ...

. This is due to the nature of tissue fusion between mates and the continuous production of sperm by the male. Unlike all other ceratioids, males do not have large nostrils for tracking species-specific

pheromone A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavio ...

s emitted by the female. Instead, they have large eyes that degenerate upon attachment to the female. Parasitic males are consistently larger-bodied than free-living/pelagic males; the largest known pelagic males reach , while 8 parasitic males attached to a single female ranged in size from , likely an indicator of the order of their attachment (biggest males attaching earliest). Parasitic males were found to be more somatically developed than pelagics, and unlike previously thought, they do not "degenerate"; they retain the

rays Ray or RAY may refer to: Fish * Ray (fish), any cartilaginous fish of the superorder Batoidea * Ray (fish fin anatomy), the bony or horny spine on ray-finned fish Science and mathematics * Half-line (geometry) or ray, half of a line split at an ...

on all of their fins. When surgically removed from a female, parasitic males are still able to swim to some extent.

References

External links

* * {{Taxonbar, from=Q1851870 Ceratiidae Fish described in 1883 Taxa named by Theodore Gill