The spearfish remora (''Remora brachyptera'') is a species of

remora The remora (), sometimes called suckerfish, is any of a family (Echeneidae) of ray-finned fish in the order Carangiformes. Depending on species, they grow to long. Their distinctive first dorsal fins take the form of a modified oval, sucker-li ...

with a worldwide distribution in tropical and subtropical seas. Remoras attach themselves to other fish with a sucker on the head and this fish is almost exclusively found living on

billfish The term billfish refers to a group of saltwater predatory fish characterised by prominent pointed bills (rostra), and by their large size; some are longer than . Extant billfish include sailfish and marlin, which make up the family Istiophor ...

es or

swordfish Swordfish (''Xiphias gladius''), also known as broadbills in some countries, are large, highly migratory predatory fish characterized by a long, flat, pointed bill. They are a popular sport fish of the billfish category, though elusive. Swordfis ...

es, and sometimes on

shark Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimo ...

Description

This species can reach in

total length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish ...

, though most do not exceed . It is an elongated cylindrical fish, usually whitish or pale blue in life, but tan or dusky-brown when dead. The rather flattened head has an oblong disc or sucker with 14 to 17 transverse plates with which it clings to its

host A host is a person responsible for guests at an event or for providing hospitality during it. Host may also refer to: Places * Host, Pennsylvania, a village in Berks County People *Jim Host (born 1937), American businessman * Michel Host ...

. The dorsal and anal fins are long and set far back on the body. The dorsal fin has between 27 and 34 soft rays, the pectoral fin has 23 to 27 rays and the anal fin 25 to 34 rays. The caudal fin has a straight edge. The sucker reaches no further than the pectoral fins, and the outer two-thirds of the pectoral rays are flexible. There are up to 21

gill raker Gill rakers in fish are bony or cartilaginous processes that project from the branchial arch (gill arch) and are involved with suspension feeding tiny prey. They are not to be confused with the gill filaments that compose the fleshy part of the ...

s in the first

branchial arch Branchial arches, or gill arches, are a series of bony "loops" present in fish, which support the gills. As gills are the primitive condition of vertebrates, all vertebrate embryos develop pharyngeal arches, though the eventual fate of these arc ...

Biology

The spearfish remora attaches itself with its disc to a host fish, with juveniles often attaching in the gill chambers. Host fish include the

sailfish The sailfish is one or two species of marine fish in the genus ''Istiophorus'', which belong to the family Istiophoridae (marlins). They are predominantly blue to gray in colour and have a characteristically large dorsal fin known as the sa ...

, the

white marlin The white marlin (''Kajikia albida''), also known as Atlantic white marlin, marlin, skilligalee, is a species of billfish that lives in the epipelagic zone of the tropical and subtropical Atlantic Ocean. They are found between the latitudes of 45� ...

, the

black marlin The black marlin (''Istiompax indica'') is a species of marlin found in tropical and subtropical areas of the Indian and Pacific Oceans. With a maximum published length of and weight of , it is one of the largest marlins and also one of the la ...

, the

striped marlin The striped marlin (''Kajikia audax'') is a species of marlin found in tropical to temperate Indo-Pacific oceans not far from the surface. It is a desirable commercial and game fish. The striped marlin is a predator that hunts during the day in t ...

and the

; all these fish swim faster than does the remora, and it is not clear how the remora attaches to the host in the first place. The remora can move about the body surface of its host and is capable of short bursts of independent swimming. The diet includes parasitic copepods removed from the body of the host, but these do not seem to form such a large percentage of the diet of the spearfish remora as it does for the

common remora The common remora (''Remora remora'') is a pelagic marine fish belonging to family Echeneidae. The dorsal fin, which has 22 to 26 soft rays, acts as a suction cup, creating a vacuum to allow it to attach to larger marine animals, such as whales ...

(''Remora remora''). Although more than one remora can attach to a single host, it is not clear how remoras come together to breed.

References

External links

Photograph
{{DEFAULTSORT:remora, spearfish

spearfish remora The spearfish remora (''Remora brachyptera'') is a species of remora with a worldwide distribution in tropical and subtropical seas. Remoras attach themselves to other fish with a sucker on the head and this fish is almost exclusively found livi ...

Taxa named by Richard Thomas Lowe