Sepiida. This order is made up of cuttlefish, which have an internal shell called the cuttlebone that is used to control buoyancy.
Nautilida. This order is made up of nautilis, which have a unique planispiral shell, and move via jet propulsion. They're morphologically veyr similar to their ancient relatives, and are often called living fossils.
Гигантская австралийская каракатица (Sepia apama) — вид головоногих моллюсков из рода настоящих каракатиц семейства каракатиц (Sepiidae). Достигая 50 см в длине мантии и свыше 10,5 кг в живом весе, считается крупнейшей каракатицей в мире.Их называют «рок-звездами океана», потому что при жизненном цикле всего лишь в 12-18 месяцев, они живут быстро и умирают молодыми.
Гигантская каракатица – эндемический вид, обитающий исключительно в прибрежных водах на юге, юго-западе и юго-востоке Австралии (от побережья штата Квинсленд до залива Акул в Западной Австралии). Встречается на глубине не более 100 метров, но чаще всего — на мелководье.
Непонятно по какой причине, но природа наделила этих живых существ 3-мя сердцами. Одно отвечает за снабжение кровью нервной системы, а остальные два — за работу жабр.Эти каракатицы прославились способностью моментально менять свой окрас, который чаще всего зависит от настроения животного или окружающей среды. Также он сильно меняется у самцов в брачный период. В брачный период или во время нападения на добычу их окраска приобретают металлический блеск и покрывается яркими светящимися точками.
Эти гиганты ведут дневной образ жизни. Большую часть времени проводят, укрывшись среди зарослей водорослей, каменистых рифов или зарывшись на морском дне. Большую часть энергии они тратят не на активность, а на рост. Очень любопытны и любят поиграть, чем часто пользуются дайверы.
The giant Australian cuttlefish (Sepia apama) is a species of cephalopod from the genus of true cuttlefish of the cuttlefish family (Sepiidae). Reaching 50 cm in mantle length and over 10.5 kg in live weight, they are considered the largest cuttlefish in the world. They are called the “rock stars of the ocean” because, with a life cycle of only 12-18 months, they live fast and die young .
The giant cuttlefish is an endemic species found exclusively in coastal waters in the south, south-west and south-east of Australia (from the coast of Queensland to Shark Bay in Western Australia). It is found at a depth of no more than 100 meters, but most often in shallow water.
It is unclear for what reason, but nature endowed these living creatures with 3 hearts. One is responsible for supplying blood to the nervous system, and the other two are responsible for the functioning of the gills. These cuttlefish are famous for their ability to instantly change their color, which most often depends on the mood of the animal or the environment. It also changes greatly in males during the mating season. During the mating season or during an attack on prey, their color acquires a metallic sheen and is covered with bright luminous dots.
These giants are diurnal. They spend most of their time hidden among kelp beds, rocky reefs, or buried on the seabed. They spend most of their energy not on activity, but on growth. They are very curious and love to play, which divers often take advantage of.
No, it's not a melting scoop of stracciatella ice cream. It's the Pyjama squid (Sepioloidea lineolata)!
Like their cousins the bobtails, they often bury in the sediment. They're in the order Sepiida, which includes bobtails, cuttlefish, bottletails, and these cuties.
Some articles on the internet will say stuff like "These animals are technically cuttlefish" and... listen... I don't know who said that, but whoever said it is wrong, and now sources all over the damn internet are repeating it, and like... I shouldn't let it bother me, ya know? But it does, unfortunately, make me feel like my eyeballs are going to fall out of my head.
Because words MEAN something, you know? And the word cuttlefish means an animal with a cuttlebone in it. The cuttlefish are a distinct bunch of critters. Their fins go around their whole bodies*, they have W shaped pupils, but most critically, they have a buoyancy device called a cuttlebone. That cuttlebone keeps them neutrally buoyant- so they neither float nor sink. They just chill. They're able to control the buoyancy with gas exchange between their blood and the little gas chambers in that cuttlebone. The other members of the Sepiida, the bottletails, pyjama squid, and bobtails, they don't have any of that. Sure, they're totally, 100%, most closely related among the cephalopods to cuttlefish, but... cuttlefish... are their own little group within that branch of the family tree.
*Ok to be fair, it's very easy to confuse cuttlefish and reef squid, but that's a whole other post.
Commission of Azad for @sepiidae! I have such a soft spot for mesmers... It was super challenging and fun to incorporate the different aesthetics and designs of Melandru, Aurene, and risen stuff!!
If you haven't done it already, I would like to submit the clever cuttlefish~
Animal of the day: Cuttlefish!
Cuttlefish are marine molluscs of the order Sepiida! They are cephalopods, like squid, octopuses, and nautiluses. They have a unique internal shell called the cuttlebone which is used to control their bouyancy.
Cuttlefish are masters of disguise and can camouflage incredibly well by changing their skin colour! They can display as many as 12 to 14 patterns, changing colours within a second.
Here is a juvenile cuttlefish camouflaging itself against some sand! Research into biological colour changing, such as that of the cuttlefish, has led to advancements in engineering, such as artificial chromatophores. These could eventually be used in clothing to provide better camouflage for humans!
"Metasepia pfefferi - commonly known as the flamboyant cuttlefish, is a species found in tropical Indo-Pacific waters off northern Australia, southern New Guinea, as well as numerous islands of the Philippines, Indonesia and Malaysia."