31/12/2021
Good evening my dear friends .. I wish you all a happy new year ..
The remoras sometimes called suckerfish are a family ( Echeneidae ) of ray-finned fish in the order Perciformes . 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 . The disk is made up of stout , flexible membranes that can be raised and lowered to generate suction . By sliding backward , the remora can increase the suction , or it can release itself by swimming forward . Remoras sometimes attach to small boats , and have been observed attaching to divers as well . They swim well on their own , with a sinuous , or curved , motion . Remora front dorsal fins have evolved to enable them to adhere by suction to smooth surfaces and they spend their lives clinging to a host animal such as a whale , turtle , shark or ray . 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 . Although it was initially believed that remoras fed off particulate matter from the host's meals , this has been shown to be false , in reality , their diets are composed primarily of host f***s . Remoras are tropical open-ocean dwellers , but are occasionally found in temperate or coastal waters if they have attached to large fish that have wandered into these areas . In the mid-Atlantic Ocean , spawning usually takes place in June and July , in the Mediterranean Sea , it occurs in August and September . The sucking disc begins to show when the young fish are about 1 cm long . When the remora reaches about 3 cm , the disc is fully formed and the remora can then attach to other animals . The remora's lower jaw projects beyond the upper , and the animal lacks a swim bladder . The relationship between a remora and its host is most often taken to be one of commensalism , specifically phoresy .. Light house dive site ..
