Sharksuckers and Whale Shark

Description:

They grow to 7–75 cm long. Their distinctive first dorsal fins take 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.

Habitat:

Cosmopolitan in warm waters. Sharksuckers are known to attach itself temporarily by its modified dorsal fin used as a sucking disc to various hosts.

Notes:

It is probably a mutualistic arrangement as the remora can move around on the host, removing ectoparasites and loose flakes of skin, while benefiting from the protection provided by the host and the constant flow of water across its gills.