Cephalopods- The Vampire Squid & Berry's Bobtail Squid BY EMILY GUO & JANICE FUNG

1. 1. Classification:

1.1. Vampire squids, also scientifically known as Vampyroteuthis infernalis, is classified as a Cephalopoda, and is in the Coleoidea subclass category. Some more of their classifications are as listed below:

1.2. Superorder – Octopodiformes

1.3. Order – Vampyromorphida

1.4. Suborder – Vampyromorphina

1.5. Family – Vampyroteuthidae

1.6. Genus – Vampyroteuthis

1.7. Species – V. Infernalis

2. 2. Habitat

2.1. Organisms such as the Vampire squid are among one of the marine animals that are much distributed globally. They can be found in tropical to temperate deep seas globally, within latitudes 40 degrees north and 40 degrees south of the equator, at depths of 600 to 1200 m. Since Vampire squids possess large gill surface area to absorb oxygen, they are able to go below 50% oxygen saturation, where the waters are as cold as 2-6 oC.

3. 3. General Body Structure: http://atlanticseafoodmarket.com/wp-content/uploads/2014/07/squid-diagram.gif

3.1. There are more than 300 different subspecies of squid in the whole world, however some of the features of squids, regardless of what subspecies they may belong to, have in common with each other. The three standard features of a squid’s body are the head, mantle and arms. The mantle acts as a wall sheath that covers all of the internal organs, and then branches out into flaps and tentacles. They protrude further beyond the organs. A structure called the pen, is a structure that holds muscles and organs together, and is found on the inside of the mantle. Every squid has undoubtedly, eight arms with two rows of suckers on the undersides and usually 2 long, feeding tentacles additionally.

3.2. Furthermore, they also contain three hearts within their system. Two of these exist to assist the gills in respiration, while the larger central heart pumps blood throughout their bodies, like us humans’ heart do. Squids all have sharp mouths shaped like beaks made out of chitin that they use to shred and kill their prey, and impossible to be digested even by a larger predator. Some species are able to grow up to forty feet long, but most squids are only able to grow not more than 24 inches in length.

4. 4/5. Adaptations & Survival Benefits:

4.1. In order to protect itself, the Vampire squid has tentacles that it can draw and then web itself backwards up over its own body into a pineapple-like posture. Despite having no ink sacs within them to blind predators closing in on them, when they web themselves backwards, the inner mantle, which is very dark, is exposed and therefore camouflages them in the lightless ocean around it. They also have organs known as photophores which produce bioluminescent sticky mucus that glow for up to 10 minutes and escape from predators. Most squids are not able to survive in the oxygen minimal layer of the ocean, where there is less than 5% oxygen saturation and almost lightless, but the Vampire squid can do so as they have a very slow metabolism so it does not need a lot of oxygen to survive. It simply drifts rather than swim most of the time, and it uses the least ox method during their feeding period, so energy is conserved.

4.2. Not to mention they also possess statoliths that keep it buoyant, and while they use their fins to move, they can propel forwards extremely fast using jet propulsion when they sense danger. They swim as fast as two body lengths per second, though this speed can only be maintained for a very short period.

5. Pictures 1 http://blogs.discovermagazine.com/notrocketscience/files/2012/09/Vampire_squid.jpg

5.1. Picture 2 http://cr2chicago.weebly.com/uploads/9/5/9/4/9594564/7456178_orig.jpeg

6. Video

7. 1. Classification:

7.1. Class: Cephalopoda

7.2. Subclass: Coleoidea

7.3. Superorder: Decapodiformes

7.4. Order: Sepiolida

7.5. Family: Sepiolidae

7.6. Genus: Euprymna

7.7. Species: E. berryi

8. 2. Habitat:

8.1. They are usually found in shallow waters in lagoons and coastal regions where they burry themselves in the sand and soft sediments, but leaving just their eyes visible. They live in tropical waters, in areas such as the Indo-Pacific region extending from Indonesia to the Philippines.

8.2. Image 1 http://www.diverosa.com/Gili/IGI-39%20Berry's%20bobtail%20squid,%20Euprymna%20berryi.jpg

9. 4. Adaptations:

9.1. Video:

9.2. Bobtail squids all have a symbiotic relationship with a bioluminescent bacteria called Vibrio fischeri. This bacteria allows the squid to ‘produce’ light. Bioluminescent organisms produce light through chemical reactions occurring in its body. In this case, the bobtail squid produces its light in its light organ located in their mantle. Sugar and amino acid solution is supplied to the bacteria from the squid which in return the bioluminescent bacteria is able to camouflage the squid’s shadow. From underneath, a predator wouldn’t be able to see the squid because the bacteria mimics the amount of light hitting its mantle. This makes the underside look like the rest of the ocean.

10. 5. Survival Benefits:

10.1. Because the size of the bobtail squid ranges from only 10-50 mm, they are small and vulnerable, but having bioluminescence helps them survive in many ways. Counter illumination: like stated in the squid’s adaptation, predators from underneath won’t be able to spot them because they cannot locate a prey’s silhouette. The bobtail squid expels almost 95% of the bacteria in the morning when it goes to sleep so that they won’t produce light when asleep and attract unwanted attention. The release of the bacteria also allows other baby squids to take in and use the bacteria.

11. References:

11.1. Bobtail squid. (2015). Retrieved 31 August, 2015 from: https://en.wikipedia.org/wiki/Bobtail_squid Euprymna berryi. (2015). Retrieved 31 August, 2015 from: https://en.wikipedia.org/wiki/Euprymna_berryi Berry’s Bobtail Squid. (n.d). Retrieved 31 August, 2015 from: http://www.whatsthatfish.com/fish/berrys-bobtail-squid/1967 Bioluminescence. (n.d). Retrieved 1 September, 2015 from: http://education.nationalgeographic.com.au/encyclopedia/bioluminescence/ Siouxsie Wiles. (25 March, 2013). The Hawaiian bobtail squid. Retrieved 1 September, 2015 from: https://www.youtube.com/watch?v=KCobcWsYOS8 Clark, L. (2013). Bioluminescent Bacteria. Retrieved 2 September, 2015 from: http://www.wired.co.uk/news/archive/2013-04/2/glowing-squid-bacteria-rhythms

11.2. Vampire Squid. (n.d). Retrieved 30 August, 2015 from: http://www.squid-world.com/vampire-squid/ Vampire Squid- Species Overview. (n.d). Retrieved 1 September, 2015 from: http://www.aquariumofpacific.org/onlinelearningcenter/species/vampire_squid Vampire squid. (2015). Retrieved 1 September, 2015 from: https://en.wikipedia.org/wiki/Vampire_squid Headquarters For Squid. (2015). Retrieved 1 September, 2015 from: http://atlanticseafoodmarket.com/2015/02/headquarters-squid-ct/ MBARI. (26 September, 2012). What the vampire squid really eats. Retrieved 2 September, 2015 from: https://www.youtube.com/watch?v=X8oWnbcLI40