The ocean sunfish, Mola mola, or common mola, is the heaviest known bony fish in the world. It has an average adult weight of 1,000 kg (2,200 lb). 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. Sunfish can be as tall as they are long when their dorsal and ventral fins are extended. Sunfish live on a diet that consists mainly of jellyfish, but because this diet is nutritionally poor, they consume large amounts in order to develop and maintain their great bulk. Females of the species can produce more eggs than any other known vertebrate.[1] Sunfish fry resemble miniature pufferfish, with large pectoral fins, a tail fin and body spines uncharacteristic of adult sunfish.
Adult sunfish are vulnerable to few natural predators, but sea lions, orcas and sharks will consume them. Among humans, sunfish are considered a delicacy in some parts of the world, including Japan, the Korean peninsula and Taiwan, but sale of their flesh is banned in the European Union.[2] Sunfish are frequently, though accidentally, caught in gillnets, and are also vulnerable to harm or death from encounters with floating trash, such as plastic bags.
A member of the order Tetraodontiformes, which also includes pufferfish, porcupinefish and filefish, the sunfish shares many traits common to members of this order. It was originally classified as Tetraodon mola under the pufferfish genus, but it has since been given its own genus, Mola, with two species under it. The ocean sunfish, Mola mola, is the type species of the genus.
Fins
In the course of its evolution, the caudal fin (tail) of the sunfish disappeared, to be replaced by a lumpy pseudo-tail, the clavus. This structure is formed by the convergence of the dorsal and anal fins.[13][14] The smooth-denticled clavus retains twelve fin rays,[15] and terminates in a number of rounded ossicles.[16] Without a true tail to provide thrust for forward motion and equipped with only small pectoral fins, Mola mola relies on its long, thin dorsal and anal fins for propulsion, driving itself forward by moving these fins from side to side.[11]
Ocean sunfish often swim near the surface, and their protruding dorsal fins are sometimes mistaken for those of sharks.[17] However, it is possible to distinguish a shark from a sunfish, by observing the trajectory made by the dorsal fin on the surface, while the fish itself moves underwater and remains unseen. Sharks, like most fish, swim by waving the tail sideways while keeping the dorsal fin moving in a straight line. The sunfish, on the other hand, swings its dorsal fin and anal fin in its characteristic sculling motion. Thus, the sideways movement of the dorsal fin on the surface can be used to identify the sunfish.[http://en.wikipedia.org/wiki/Mola_mola]
Krill
Krill is a shrimp-like marine invertebrate animal. These small crustaceans are important organisms of the zooplankton, particularly[1] as food for baleen whales, manta rays, whale sharks, crabeater seals, other seals, and a few seabird species that feed almost exclusively on them. Another name is euphausiids, after their taxonomic order Euphausiacea. The name krill comes from the Norwegian word krill meaning "young fry of fish," which is also often attributed to other species of fish.
Krill occur in all oceans of the world. They are considered an important trophic connection - near the bottom of the food chain - because they feed on phytoplankton and to a lesser extent zooplankton, converting these into a form suitable for many larger animals for whom krill makes up the largest part of their diet. In the Southern Ocean, one species, the Antarctic krill, Euphausia superba, makes up an estimated biomass of over 500 million tonnes, roughly twice that of humans. Of this, over half is eaten by whales, seals, penguins, squid and fish each year, and is replaced by growth and reproduction. Most krill species display large daily vertical migrations, thus providing food for predators near the surface at night and in deeper waters during the day.
Krill tastes salty and somewhat stronger than shrimp. For mass-consumption and commercially prepared products they must be peeled, because their exoskeleton contains fluorides, which are toxic in high concentrations.[41] Excessive intake of okiami may cause diarrhea.
[http://en.wikipedia.org/wiki/Krill]
Puffer fish are the second most poisonous vertebrate in the world, the first being a Golden Poison Frog. The skin and certain internal organs of many tetraodontidae are highly toxic to humans, but nevertheless the meat of some species is considered a delicacy in both Japan (as fugu) and Korea (as bok). If one is caught while fishing, it is recommended that thick gloves be worn to avoid poisoning and getting bitten when removing the hook.
Tetraodontidae is a family of primarily marine and estuarine fish. The family includes many familiar species which are variously called puffers, balloonfish, blowfish, bubblefish, globefish, swellfish, toadfish, toadies, honey toads, and sea squab.[1] They are morphologically similar to the closely related porcupinefish, which have large conspicuous spines (unlike the small, almost sandpaper-like spines of Tetraodontidae). The scientific name, Tetraodontidae, refers to the four large teeth, fused into an upper and lower plate, which are used for crushing the shells of crustaceans and mollusks, and red worms, their natural prey.Butterflyfish
The butterflyfish are a group of conspicuous tropical marine fish of the family Chaetodontidae; the bannerfish and coralfish are also included in this group. Found mostly on the reefs of the Atlantic, Indian and Pacific Oceans, there are approximately 120 species in 10 genera.
Butterflyfish look like smaller versions of angelfish (Pomacanthidae) but unlike these lack preopercle spines at the gill covers. Some members of the genus Heniochus resemble the Moorish Idol (Zanclus cornutus) of the monotypic Zanclidae. Among the paraphyletic "Perciformes", the former are probably not too distantly related to butterflyfish, whereas the Zanclidae seem far less close.
Raccoon butterflyfish
 Copperband butterflyfish, Chelmon rostratus |  The enigmatic Johnrandallia nigrirostris |  Sunburst butterflyfish, Chaetodon kleinii (sometimes placed in Lepidochaetodon) |  Bluelashed butterflyfish, Chaetodon bennetti (sometimes placed in Megaprotodon) |
Marine angelfish are perciform fish of the family Pomacanthidae. They are found on shallow reefs in the tropical Atlantic, Indian, and mostly western Pacific oceans. The family contains seven genera and approximately 86 species. They should not be confused with the freshwater angelfish, tropical cichlids of the Amazon River basin.
With their vibrant colours and deep, laterally compressed bodies, marine angelfishes are some of the more conspicuous residents of the reef. They most closely resemble the butterflyfishes, a related family of similarly showy reef fish. Marine angelfish are distinguished from butterflyfish by the presence of strong preopercle spines (part of the gill covers) in the former. This feature also explains the family name Pomacanthidae; from the Greek poma meaning "cover" and akantha meaning "thorn".
Many species of marine angelfishes have streamer-like extensions of the soft dorsal and anal fins. The fish have small mouths, relatively large pectoral fins and rounded to lunate tail fins. The largest species, the gray angelfish, Pomacanthus arcuatus, may reach a length of 60 cm; at the other extreme, members of the genus Centropyge do not exceed 15 cm. A length of 20 to 30 cm is average for the rest of the family. The smaller species are popular amongst aquarists, whereas the largest species are occasionally sought as a food fish; however, there have been reports of ciguatera poisoning as a result of eating marine angelfish.
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