Remora
Encyclopedia
The remora sometimes called a suckerfish or sharksucker, is an elongated, brown fish
in the order
Perciformes
and family Echeneidae. They grow to 30–90 centimetres long (1–3 ft), and their distinctive first dorsal fin
takes the form of a modified oval sucker-like organ with slat-like structures that open and close to create suction and take a firm hold against the skin of larger marine animals. By sliding backward, the remora can increase the suction, or it can release itself by swimming forward. Remoras sometimes attach to small boats. They swim well on their own, with a sinuous, or curved, motion.
Remoras are primarily tropical open-ocean dwellers, occasionally found in temperate
or coastal waters if they have attached to large fish that have wandered into these areas. In the mid-Atlantic
, spawning usually takes place in June and July; in the Mediterranean, in August and September. The sucking disc begins to show when the young fish are about 1 centimetre long. When the remora reaches about 3 centimetres, the disc is fully formed and the remora is then able to hitch a ride. The remora's lower jaw projects beyond the upper, and the animal lacks a swim bladder.
Some remoras associate primarily with specific host species. Remoras are commonly found attached to sharks, manta ray
s, whales, turtles and dugong
(hence the common names 'sharksucker' and 'whalesucker'). Smaller remoras also fasten onto fish like tuna and swordfish
, and some small remoras travel in the mouths or gills of large manta rays, ocean sunfish
, swordfish and sailfish
.
The relationship between remoras and their perfect hosts is most often taken to be one of commensalism
, specifically phoresy. The host they attach to for transport gains nothing from the relationship, but also loses little. The remora benefits by using the host as transport and protection and also feeds on materials dropped by the host. There is controversy whether a remora's diet is primarily leftover fragments, or the feces of the host. In some species (Echeneis naucrates and E. neucratoides) consumption of host feces is strongly indicated in gut dissections. For other species, such as those found in a host's mouth, scavenging of leftovers is more likely. For some remora and host pairings the relationship is closer to mutualism, with the remora cleaning bacteria and other parasites from the host.
, especially from eastern Africa near Zanzibar
and Mozambique
, and from northern Australia near Cape York
and Torres Strait
.
Similar reports come from Japan and from the Americas. Some of the first records of the "fishing fish" in the Western literature come from the accounts of the second voyage of Christopher Columbus
. However, Leo Wiener
considers the Columbus accounts to be apocryphal: what was taken for accounts of the Americas may have in fact been notes that Columbus derived from accounts of the East Indies, his desired destination.
, in which the remora is blamed for the defeat of Mark Antony
at the Battle of Actium
and (indirectly) for the death of Caligula
. A modern version of the story is given by Jorge Luis Borges
in Book of Imaginary Beings
(1957).
Because of the shape of the jaws, appearance of the sucker and coloration of the remora, it sometimes appears to be swimming upside down. This probably led to the older common name reversus, although this might also derive from the fact that the remora frequently attaches itself to the tops of manta rays or other fish, so that the remora is upside down while attached.
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
in the order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...
Perciformes
Perciformes
The Perciformes, also called the Percomorphi or Acanthopteri, is one of the largest orders of vertebrates, containing about 40% of all bony fish. Perciformes means perch-like. They belong to the class of ray-finned fish and comprise over 7,000 species found in almost all aquatic environments...
and family Echeneidae. They grow to 30–90 centimetres long (1–3 ft), and their distinctive first dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
takes the form of a modified oval sucker-like organ with slat-like structures that open and close to create suction and take a firm hold against the skin of larger marine animals. By sliding backward, the remora can increase the suction, or it can release itself by swimming forward. Remoras sometimes attach to small boats. They swim well on their own, with a sinuous, or curved, motion.
Remoras are primarily tropical open-ocean dwellers, occasionally found in temperate
Temperate
In geography, temperate or tepid latitudes of the globe lie between the tropics and the polar circles. The changes in these regions between summer and winter are generally relatively moderate, rather than extreme hot or cold...
or coastal waters if they have attached to large fish that have wandered into these areas. In the mid-Atlantic
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
, spawning usually takes place in June and July; in the Mediterranean, in August and September. The sucking disc begins to show when the young fish are about 1 centimetre long. When the remora reaches about 3 centimetres, the disc is fully formed and the remora is then able to hitch a ride. The remora's lower jaw projects beyond the upper, and the animal lacks a swim bladder.
Some remoras associate primarily with specific host species. Remoras are commonly found attached to sharks, manta ray
Manta ray
The manta ray is the largest species of the rays. The largest known specimen was more than across, with a weight of about . It ranges throughout waters of the world, typically around coral reefs...
s, whales, turtles and dugong
Dugong
The dugong is a large marine mammal which, together with the manatees, is one of four living species of the order Sirenia. It is the only living representative of the once-diverse family Dugongidae; its closest modern relative, Steller's sea cow , was hunted to extinction in the 18th century...
(hence the common names 'sharksucker' and 'whalesucker'). Smaller remoras also fasten onto fish like tuna and swordfish
Swordfish
Swordfish , also known as broadbill in some countries, are large, highly migratory, predatory fish characterized by a long, flat bill. They are a popular sport fish of the billfish category, though elusive. Swordfish are elongated, round-bodied, and lose all teeth and scales by adulthood...
, and some small remoras travel in the mouths or gills of large manta rays, ocean sunfish
Ocean sunfish
The ocean sunfish, Mola mola, or common mola, is the heaviest known bony fish in the world. It has an average adult weight of . The species is native to tropical and temperate waters around the globe. It resembles a fish head with a tail, and its main body is flattened laterally...
, swordfish and sailfish
Sailfish
'Sailfish' are two species of fish in the genus Istiophorus, living in warmer sections of all the oceans of the world. They are predominately blue to gray in color and have a characteristic erectile dorsal fin known as a sail, which often stretches the entire length of the back...
.
The relationship between remoras and their perfect hosts is most often taken to be one of commensalism
Commensalism
In ecology, commensalism is a class of relationship between two organisms where one organism benefits but the other is neutral...
, specifically phoresy. The host they attach to for transport gains nothing from the relationship, but also loses little. The remora benefits by using the host as transport and protection and also feeds on materials dropped by the host. There is controversy whether a remora's diet is primarily leftover fragments, or the feces of the host. In some species (Echeneis naucrates and E. neucratoides) consumption of host feces is strongly indicated in gut dissections. For other species, such as those found in a host's mouth, scavenging of leftovers is more likely. For some remora and host pairings the relationship is closer to mutualism, with the remora cleaning bacteria and other parasites from the host.
Species
There are eight species in four genera:- Genus EcheneisEcheneis (genus)Echeneis is a genus of remora, containing two extant species:* Live sharksucker, Echeneis naucrates Linnaeus, 1758.* Whitefin sharksucker, Echeneis neucratoides Zuiew, 1786.-References:* at Zipcodezoo.com...
- Live sharksucker, Echeneis naucrates LinnaeusCarolus LinnaeusCarl Linnaeus , also known after his ennoblement as , was a Swedish botanist, physician, and zoologist, who laid the foundations for the modern scheme of binomial nomenclature. He is known as the father of modern taxonomy, and is also considered one of the fathers of modern ecology...
, 1758. - Whitefin sharksucker, Echeneis neucratoides Zuiew, 1786.
- Live sharksucker, Echeneis naucrates Linnaeus
- Genus Phtheirichthys
- Slender suckerfishSlender suckerfishThe slender suckerfish or lousefish, Phtheirichthys lineatus, is a rare species of remora, family Echeneidae, and the only member of the genus Phtheirichthys. It is found around the world in tropical and subtropical seas....
, Phtheirichthys lineatus (Menzies, 1791).
- Slender suckerfish
- Genus RemoraRemora (genus)Remora is a genus of suckerfish. It contains the following species:* Remora australis – whalesucker* Remora brachyptera – spearfish remora* Remora osteochir – marlin sucker...
- WhalesuckerWhalesuckerThe whalesucker, Remora australis, is a species of remora in the family Echeneidae, so named because it attaches itself exclusively to cetaceans. It is found worldwide in tropical and warm waters; in the western Atlantic Ocean it occurs from Texas to Brazil, and in the eastern Pacific Ocean it...
, Remora australis (Bennett, 1840). - Spearfish remoraSpearfish remoraThe spearfish remora, Remora brachyptera, is a remora of the family Echeneidae, found around the world in tropical and subtropical seas. Its length is up to 50 cm.-References:...
, Remora brachyptera (Lowe, 1839). - Marlin suckerMarlin suckerThe marlin sucker, Remora osteochir, is a remora of the family Echeneidae, found all over the world in tropical and temperate seas. Its length is up to 40 cm.-References:...
, Remora osteochir (CuvierGeorges CuvierGeorges Chrétien Léopold Dagobert Cuvier or Jean Léopold Nicolas Frédéric Cuvier , known as Georges Cuvier, was a French naturalist and zoologist...
, 1829). - Common remoraCommon remoraThe common remora, Remora remora, is a pelagic marine fish belonging to family Echeneidae. Remora remora is different from other remoras in the family Echeneidae by the modification of its dorsal fin...
, Remora remora (LinnaeusCarolus LinnaeusCarl Linnaeus , also known after his ennoblement as , was a Swedish botanist, physician, and zoologist, who laid the foundations for the modern scheme of binomial nomenclature. He is known as the father of modern taxonomy, and is also considered one of the fathers of modern ecology...
, 1758).
- Whalesucker
- Genus Remorina
- White suckerfishWhite suckerfishThe white suckerfish or mantasucker, Remorina albescens, is a species of remora in the family Echeneidae, a group of elongate marine fish with adhesive discs for attaching to larger organisms...
, Remorina albescens (TemminckCoenraad Jacob TemminckCoenraad Jacob Temminck was a Dutch aristocrat and zoologist.Temminck was the first director of the National Natural History Museum at Leiden from 1820 until his death. His Manuel d'ornithologie, ou Tableau systematique des oiseaux qui se trouvent en Europe was the standard work on European birds...
& SchlegelHermann SchlegelHermann Schlegel was a German ornithologist and herpetologist.-Early life and education:Schlegel was born at Altenburg, the son of a brassfounder. His father collected butterflies, which stimulated Schlegel's interest in natural history...
, 1850).
- White suckerfish
Use for fishing
Some cultures use remoras to catch turtles. A cord or rope is fastened to the remora's tail, and when a turtle is sighted the fish is released from the boat; it usually heads directly for the turtle and fastens itself to the turtle's shell, and then both remora and turtle are hauled in. Smaller turtles can be pulled completely into the boat by this method, while larger ones are hauled within harpooning range. This practice has been reported throughout the Indian OceanIndian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
, especially from eastern Africa near Zanzibar
Zanzibar
Zanzibar ,Persian: زنگبار, from suffix bār: "coast" and Zangi: "bruin" ; is a semi-autonomous part of Tanzania, in East Africa. It comprises the Zanzibar Archipelago in the Indian Ocean, off the coast of the mainland, and consists of numerous small islands and two large ones: Unguja , and Pemba...
and Mozambique
Mozambique
Mozambique, officially the Republic of Mozambique , is a country in southeastern Africa bordered by the Indian Ocean to the east, Tanzania to the north, Malawi and Zambia to the northwest, Zimbabwe to the west and Swaziland and South Africa to the southwest...
, and from northern Australia near Cape York
Cape York Peninsula
Cape York Peninsula is a large remote peninsula located in Far North Queensland at the tip of the state of Queensland, Australia, the largest unspoilt wilderness in northern Australia and one of the last remaining wilderness areas on Earth...
and Torres Strait
Torres Strait
The Torres Strait is a body of water which lies between Australia and the Melanesian island of New Guinea. It is approximately wide at its narrowest extent. To the south is Cape York Peninsula, the northernmost continental extremity of the Australian state of Queensland...
.
Similar reports come from Japan and from the Americas. Some of the first records of the "fishing fish" in the Western literature come from the accounts of the second voyage of Christopher Columbus
Christopher Columbus
Christopher Columbus was an explorer, colonizer, and navigator, born in the Republic of Genoa, in northwestern Italy. Under the auspices of the Catholic Monarchs of Spain, he completed four voyages across the Atlantic Ocean that led to general European awareness of the American continents in the...
. However, Leo Wiener
Leo Wiener
Leo Wiener was an Americanhistorian, linguist, author and translator of Polish-Jewish origin. Wiener was born in Russia and spent the early part of his childhood there, before coming to the United States alone, with the purpose of creating a vegetarian commune in Belize...
considers the Columbus accounts to be apocryphal: what was taken for accounts of the Americas may have in fact been notes that Columbus derived from accounts of the East Indies, his desired destination.
Mythology
In ancient times, the remora was believed to stop a ship from sailing. In Latin, remora means "delay," while the genus name Echeneis comes from Greek echein ("to hold") and naus ("a ship"). There is a notable account by Pliny the YoungerPliny the Younger
Gaius Plinius Caecilius Secundus, born Gaius Caecilius or Gaius Caecilius Cilo , better known as Pliny the Younger, was a lawyer, author, and magistrate of Ancient Rome. Pliny's uncle, Pliny the Elder, helped raise and educate him...
, in which the remora is blamed for the defeat of Mark Antony
Mark Antony
Marcus Antonius , known in English as Mark Antony, was a Roman politician and general. As a military commander and administrator, he was an important supporter and loyal friend of his mother's cousin Julius Caesar...
at the Battle of Actium
Battle of Actium
The Battle of Actium was the decisive confrontation of the Final War of the Roman Republic. It was fought between the forces of Octavian and the combined forces of Mark Antony and Cleopatra VII. The battle took place on 2 September 31 BC, on the Ionian Sea near the city of Actium, at the Roman...
and (indirectly) for the death of Caligula
Caligula
Caligula , also known as Gaius, was Roman Emperor from 37 AD to 41 AD. Caligula was a member of the house of rulers conventionally known as the Julio-Claudian dynasty. Caligula's father Germanicus, the nephew and adopted son of Emperor Tiberius, was a very successful general and one of Rome's most...
. A modern version of the story is given by Jorge Luis Borges
Jorge Luis Borges
Jorge Francisco Isidoro Luis Borges Acevedo , known as Jorge Luis Borges , was an Argentine writer, essayist, poet and translator born in Buenos Aires. In 1914 his family moved to Switzerland where he attended school, receiving his baccalauréat from the Collège de Genève in 1918. The family...
in Book of Imaginary Beings
Book of Imaginary Beings
Jorge Luis Borges wrote and edited the Book of Imaginary Beings in 1957 as the original Spanish Manual de zoología fantástica, or Handbook of Fantastic Zoology, expanding it in 1967 and 1969 to the final El libro de los seres imaginarios...
(1957).
Because of the shape of the jaws, appearance of the sucker and coloration of the remora, it sometimes appears to be swimming upside down. This probably led to the older common name reversus, although this might also derive from the fact that the remora frequently attaches itself to the tops of manta rays or other fish, so that the remora is upside down while attached.