The bathypelagic zone or bathyal zone (from Greek βαθύς (bathýs), deep) is the part of the open ocean that extends from a depth of 1,000 to 4,000 m (3,300 to 13,000 ft) below the ocean surface. It lies between the mesopelagic above and the abyssopelagic below. The bathypelagic is also known as the midnight zone because of the lack of sunlight; this feature does not allow for photosynthesis-driven primary production, preventing growth of phytoplankton or aquatic plants. Although larger by volume than the photic zone, human knowledge of the bathypelagic zone remains limited by ability to explore the deep ocean.
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👉 Bathypelagic in the context of Deep sea fish
Deep-sea fish are fish that live in the darkness below the sunlit surface waters, that is below the epipelagic or photic zone of the sea. The lanternfish is, by far, the most common deep-sea fish. Other deep-sea fishes include the flashlight fish, cookiecutter shark, bristlemouths, anglerfish, viperfish, and some species of eelpout.
Only about 2% of known marine species inhabit the pelagic environment. This means that they live in the water column as opposed to the benthic organisms that live in or on the sea floor. Deep-sea organisms generally inhabit bathypelagic (1–4 km; 0.62–2.49 mi deep) and abyssopelagic (4–6 km; 2.5–3.7 mi deep) zones. However, characteristics of deep-sea organisms, such as bioluminescence can be seen in the mesopelagic (200–1,000 m; 660–3,280 ft deep) zone as well. The mesopelagic zone is the disphotic zone, meaning light there is minimal but still measurable. The oxygen minimum layer exists somewhere between a depth of 700 and 1,000 metres (2,300 and 3,300 ft) depending on the place in the ocean. This area is also where nutrients are most abundant. The bathypelagic and abyssopelagic zones are aphotic, meaning that no light penetrates this area of the ocean. These zones make up about 75% of the inhabitable ocean space.
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Bathypelagic in the context of Mesopelagic
The mesopelagic zone (Greek μέσον, middle), also known as the middle pelagic or twilight zone, is the part of the pelagic zone that lies between the photic epipelagic and the aphotic bathypelagic zones. It is defined by light, and begins at the depth where only 1% of incident light reaches and ends where there is no light; the depths of this zone are between approximately 200 to 1,000 meters (660 to 3,280 ft) below the ocean surface.
The mesopelagic zone occupies about 60% of the planet's surface and about 20% of the ocean's volume, amounting to a large part of the total biosphere. It hosts a diverse biological community that includes bristlemouths, blobfish, bioluminescent jellyfish, giant squid, and myriad other unique organisms adapted to live in a low-light environment. It has long captivated the imagination of scientists, artists and writers; deep sea creatures are prominent in popular culture.
View the full Wikipedia page for MesopelagicBathypelagic in the context of Bathyteuthida
Bathyteuthida is an order of cephalopods, consisting of small, mesopelagic to bathypelagic squid that in some ways resemble myopsid squid, such as Loligo and in others the pelagic oegopsid squid. Its two families, the Bathyteuthidae and Chtenopterygidae, each containing a single genus, have previously been included with the oegopsids.
As with the oegopsids, the Bathyteuthida lack corneal membranes covering their eyes, something common to myopsid squid, and have paired oviducts, lacking in myopsids. As with the myopsids, bathyteuthids have tentacle pockets in the head and small suckers on the buccal supports, found only in this group, Loliginidae, and Sepiidae; neither is found in true oegopsids. The Bathyteuthida do share the open ocean pelagic habitat with the oegopsid squid, uniting them in that way with that diverse group.
View the full Wikipedia page for Bathyteuthida