The Japanese spider crab (Macrocheira kaempferi) is a species of marine crab that lives in the waters around Japan. It has the largest leg span of any arthropod. They go through three main larval stages along with a prezoeal stage in order to grow to their great size.[2] The genus Macrocheira contains multiple species. Two fossil species of this genus have been found, Macrocheira ginzanensis and Macrocheira yabei, both from the Miocene of Japan.[3][4] The diverse taxonomic history is an important part of what these creatures are and how they evolved to be what they are today. They are sought by Crab fisheries, and are considered a delicacy in Japan. Conservation efforts are being put forth to protect these creatures and their population from the dangers of overfishing.[5] The Japanese spider crab is similar in appearance to the much smaller European spider crab (Maja squinado) and is not to be confused with it.

The deep-sea dragonfish (Stomiidae), also called the barbeled dragonfish, uses it's fang-like teeth to grab prey in its deep-sea environment. Like other deep-sea organisms, dragonfish have bioluminescent photophores and other adaptations that allow them to make do at extreme depths. See a photo of a dragonfish jaw up-close, and see more photos of spectacular deep-sea animals.

The vampire squid is a small cephalopod found throughout temperate and tropical oceans in extreme deep sea conditions. The vampire squid uses its bioluminescent organs and its unique oxygen metabolism to thrive in the parts of the ocean with the lowest concentrations of oxygen.

The deep sea anglerfish, also known as the humpback anglerfish, is a medium sized (7 inches/18 cm) anglerfish that lives in the bathypelagic zone of the open ocean. Living at depths of at least 6600 feet (2000 m), this species lives its life in the complete absence of sunlight. Anglerfishes, in general, are named for the modified dorsal fin spine that they use to lure prey.

Linophryne algibarbata is a leftvent sea devil in the genus Linophryne that lives in waters between 400–2,200 metres in the North Atlantic Ocean.

Blackfin Goosefish Head and front of body flattened, broad, body narrowing behind; ridge from top of eye to snout rough, with knobs, spines or ridges; bone behind eye with 2-3 spines; mouth broad, with many long, sharp teeth; gill opening large, opens entirely below and behind pectoral base; dorsal fin consists of III isolated spines on head (1st spine acts as a fishing pole, with a lure), several short spines not joined by membrane above pectoral fin; length of 3rd head spine greater than minimum distance between the 2 ridges that run along snout, length of 1st behind-head spine =/> that same minimum distance; soft dorsal fin (9-10 rays) behind, on rear of body; anal fin 8-9; pectoral fin 22-26. Dark brown above; lower surface with dark reticulations in adult; underturned inner edge of pectoral with a distinct black band, underside of base of fin gradually getting darker; no black membrane connecting rear dorsal spines. Reaches 60 cm.

Bathynomus giganteus is a species of aquatic crustacean, of the order Isopoda. It is a member of the giant isopods (Bathynomus), and it is related—albeit distantly—to shrimps and crabs. It was the first Bathynomus species ever documented, and was described in 1879 by French zoologist Alphonse Milne Edwards after the isopod was found in fishermen's nets off the coast of the Dry Tortugas in the Gulf of Mexico.

The ghostly seadevil or soft leftvent angler, Haplophryne mollis, is a species of anglerfish in the family Linophrynidae and is the only species in the genus Haplophryne. It is found in the bathypelagic and mesopelagic zones of tropical and subtropical parts of the world's oceans at depths down to about 2,250 m.

The hairy frogfish is a type of fish that’s covered in spines. These spines, which resemble strands of hair, allow the marine animal to camouflage itself against coral and seaweed. Found mostly in warm waters around the world, the hairy frogfish can also change its color to blend in with its surroundings. These animals may be excellent at hiding in plain sight. However they do something that really makes them stand out from a lot of other sea creatures. The fish—which usually grow about four inches long—don’t swim. Instead they walk on their wide fins along the seafloor as they look for snacks to eat.

The megamouth shark is a species of deepwater shark. It is rarely seen by humans and is the smallest of the three extant filter-feeding sharks alongside the whale shark and basking shark. Since its discovery in 1976, fewer than 100 specimens have been observed or caught.

The Pacific viperfish, Chauliodus macouni, is a predatory fish that lives in the bathyal zone or bathypelgic, ranging from 1000m-4000m and having an average temperature of 4 degrees Celsius. However, the pacific viperfish has been found in the mesopelagic region, above the bathypelagic.

The pelican eel (Eurypharynx pelecanoides) is a deep-sea eel rarely seen by humans, though it is occasionally caught in fishing nets. It is the only known member of the genus Eurypharynx and the family Eurypharyngidae. It belongs to the "saccopharyngiforms", members of which were historically placed in their own order, but are now considered true eels in the order Anguilliformes. The pelican eel has been described by many synonyms, yet nobody has been able to demonstrate that more than one species of pelican eel exists. It is also referred to as the gulper eel (which can also refer to members of the related genus Saccopharynx), pelican gulper, and umbrella-mouth gulper.

The goblin shark (Mitsukurina owstoni) is a rare species of deep-sea shark. Sometimes called a "living fossil", it is the only extant representative of the family Mitsukurinidae, a lineage some 125 million years old. This pink-skinned animal has a distinctive profile with an elongated, flat snout, and highly protrusible jaws containing prominent nail-like teeth. It is usually between 3 and 4 m (10 and 13 ft) long when mature, though it can grow considerably larger such as one captured in 2000 that is thought to have measured 6 m (20 ft).

The frilled shark (Chlamydoselachus anguineus) and the southern African frilled shark (Chlamydoselachus africana) are the two extant species of shark in the family Chlamydoselachidae. The frilled shark is considered a living fossil, because of its primitive, anguilliform (eel-like) physical traits, such as a dark-brown color, amphistyly (the articulation of the jaws to the cranium), and a 2.0 m (6.6 ft)–long body, which has dorsal, pelvic, and anal fins located towards the tail. The common name, frilled shark, derives from the fringed appearance of the six pairs of gill slits at the shark's throat. The two species of frilled shark are distributed throughout regions of the Atlantic and the Pacific oceans, usually in the waters of the outer continental shelf and of the upper continental slope, where the sharks usually live near the ocean floor, near biologically productive areas of the ecosystem. To live on a diet of cephalopods, smaller sharks, and bony fish, the frilled shark practices diel vertical migration to feed at night at the surface of the ocean. When hunting food, the frilled shark moves like an eel, bending and lunging to capture and swallow whole prey with its long and flexible jaws, which are equipped with 300 recurved, needle-like teeth.

Lophiomus setigerus, the Blackmouth angler, is a species of goosefish found in the Indian and western Pacific Oceans where it occurs at depths of from 30 to 800 metres (98 to 2,625 ft). This species grows to a length of 40 centimetres (16 in) TL. This species is commercially harvested for human consumption. Most notably, in South Korea where it is known as agwi (아귀), it is the key ingredient of agujjim (아구찜). This was originally invented in the town of Masan: historically, agwi fish were discarded by the fishermen, as they were considered unsellable due to their ugly appearance. But around the mid-20th century, the food stall cooks at the Masan market took up the challenge to turn the waste into a tasty dish. As it turned out, preparing L. setigerus in jjim style (steamed in a spicy and hot marinade) brought its agreeable flavor and peculiar texture out well, besides delivering a healthy dose of protein. Agwi is now a nationally popular dish, with many scores of specialist restaurants found across the country. As a side note, L. setigerus is traditionally combined in agwi with the ascidian tunicate Styela clava (mideodeok, 미더덕). Like this fish, use of tunicates as food is rather unusual.

The deep sea fish, Malacosteus niger, is commonly known as the Black Dragon Fish. Some additional common names for this species include: Northern Stoplight Loosejaw, Lightless Loosejaw, Black Loosejaw, and Black Hinged-Head. It belongs to the order of fishes called the dragonfishes, or scientifically known as the Stomiidae. It is among the top predators of the open mesopelagic zone.

The red-lipped batfish or Galapagos batfish is a fish of unusual morphology found around the Galapagos Islands and off Peru at depths of 3 to 76 m. Red-lipped batfish are closely related to rosy-lipped batfish, which are found near Cocos Island off the Pacific coast of Costa Rica.

The smooth handfish is a possibly extinct species of handfish in the genus Sympterichthys. It was endemic to waters off the coast of Tasmania, mainly the D’Entrecasteaux Channel. It was declared extinct by the IUCN Red List in 2020, marking the first entirely marine fish classified as such.

The deepsea lizardfish, Bathysaurus ferox, is an aulopiform of the family Bathysauridae, found in tropical and subtropical seas across the world. The deepsea lizardfish should not be confused with the true or "typical" lizardfishes of the related family Synodontidae. Deepsea lizardfishes were first described in 1878 by British zoologist Albert Günther, who created the generic name from ancient Greek word elements “báthos” and “saûros” meaning “lizard of the depths”. Previously recognized in the synodontidae, in 1996, Robert Karl Johnson et al. showed its relationships outside synodontidae, in its own family in the suborder Giganturoidei. At the beginning of the century, Bathysaurus ferox larvae were thought to be a distinct species called Macristium chavesi. Johnson gave evidence of the synonymy of the two species.

Lophius piscatorius, commonly known as the angler, European angler or common monkfish, is a monkfish in the family Lophiidae. It is found in coastal waters of the northeast Atlantic, from the Barents Sea to the Strait of Gibraltar, the Mediterranean and the Black Sea. Within some of its range, including the Irish Sea, this species comprises a significant commercial fishery.

Riftia pachyptila, commonly known as the giant tube worm, is a marine invertebrate in the phylum Annelida (formerly grouped in phylum Pogonophora and Vestimentifera) related to tube worms commonly found in the intertidal and pelagic zones. R. pachyptila lives on the floor of the Pacific Ocean near hydrothermal vents, and can tolerate extremely high hydrogen sulfide levels. These worms can reach a length of 3 m (9 ft 10 in), and their tubular bodies have a diameter of 4 cm (1.6 in). Ambient temperature in their natural environment ranges from 2 to 30°C.

The coffinfish (Chaunax endeavouri) is a species of sea toad of the family Chaunacidae, which consists of 17 species. It is found in salty temperate waters of southwestern Pacific, off east coast of Australia. The coffinfish was first discovered around February 1997 in Sicily, Italy by the skipper of the Libra, which was a trawler who was harbored in Mazara at the time. It can be also found in depths of 164–984.3 ft (50.0–300.0 m). Deep sea crab fishermen off the east coast of Florida pull them up from depth ranging from 5,000-8,000 feet about 54–68 miles off the coast.

Thaumatichthys axeli is a bottom-dwelling deep-sea anglerfish of the family Thaumatichthyidae. Thaumatichthys axeli lives at a depth of around 3,600 meters (in the abyssal zone), deeper than any other member of the genus Thaumatichthys. As with other members of the family, they possess a distinctive forked light organ inside their mouth, which they use to lure prey. Large, curved teeth "fringe the upper jaw like a comb". Specimens have been founding measuring up to about 50 cm.