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Overview

Brief Summary

Introduction

Periphylla periphylla is found in every ocean of the world apart from the Arctic, at 1,000 to 7,000 metres deep.Light is toxic to this jellyfish and it only moves up to shallower depths at night.Like many jellyfish Periphylla periphylla has large stinging cells on its tentacles that it uses to attack prey.It is unusual because it can produce flashes of light by a chemical reaction called bioluminescence that helps protect it from predators.
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Comprehensive Description

Biology

. Wilson was the zoologist and junior surgeon on the 1901 -1904 Discovery Expedition to the Antarctic, under Commander Robert Falcon Scott (1868 -1912). The swimming bell, or umbrella, of Periphylla periphylla can reach up to 35cm in height and 25cm in diameter.The largest specimens are found in the Antarctic ocean. Elsewhere the jellyfish are often much smaller.Its colour ranges from pale pink and orange to dark red.Morphological features include:
  • 12 tentacles
  • 16 marginal lappets
  • 8 gonads
  • a large stomach


Lifecycle
Periphylla periphylla is one of the only jellyfish known not to go through an immobile (sessile) life-stage. It remains free-living and planktonic throughout the life-cycle. Fertilised eggs develop directly into the jellyfish form (medusa). There is some evidence for courtship behaviour in this species. It has a long life-span for a jellyfish, and can live for up to 30 years.
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Distribution

Gulf of St. Lawrence; Strait of Belle Isle and as far south as Virginia
  • North-West Atlantic Ocean species (NWARMS)
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semi-cosmopolitan
  • UNESCO-IOC Register of Marine Organisms
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Geographic Range

Periphylla periphylla can be found in numerous locations around the world including the South Shetland Islands, South Sandwich Islands, South Georgia Island, the Southern Ocean, Antarctica, the Antarctic Peninsula, and other marine habitats worldwide. The only large body of water they are not found in is the Arctic Ocean. While it has a wide distribution, P. periphylla is significantly more abundant in some Norwegian Fjords.

Biogeographic Regions: nearctic (Native ); palearctic (Native ); oriental (Native ); ethiopian (Native ); neotropical (Native ); australian (Native ); antarctica (Native ); indian ocean (Native ); atlantic ocean (Native ); pacific ocean (Native ); mediterranean sea (Native )

Other Geographic Terms: cosmopolitan

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Distribution
Periphylla periphylla may be the world’s most common and widely-occurring deep-sea scyphozoan - true jellyfish. It is found in every ocean apart from the Arctic, usually from 1000–7000 metres, but rising to shallower depths at higher latitudes. It occurs in much higher concentrations in Norwegian fjords, in particular Lurefjorden, western Norway.
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Physical Description

Morphology

Physical Description

Periphylla periphylla are deep-sea medusae with twelve stiff tentacles, which extend from a thick, bell shaped body. These animals have dark red and/or brown stomachs, and are bioluminescent. They can be up to 20 cm long, and their bodies, or central domes, have a diameter of up to 35 cm. The coronal groove, located on the lower portion of the bell, helps to contain prey, and also provides flexibility for movement. The coronal groove divides the aboral surface into the central dome and the peripheral zone, which contains radial thickenings called pedalia and marginal lappets that contain some sense organs. This zone also contains the tentacles, which are useful in moving prey to the mouth. The mouth is very simple and is located on the manubrium. Externally, males and females of this species are similar. No indication of geographical or seasonal variation was reported.

The pigment that gives P. periphylla their red-brown color is protoporphyrin (also known as porphyrin), which can lead to tissue damage as a result of photosynthesis. The pigment is not harmful to this species as they do not usually stay in shallow waters.

Periphylla periphylla contain relatively high levels of lactate dehydrogenase, an enzyme important to anaerobic metabolic functions. This is likely useful for movement in ocean layers with minimal amounts of oxygen.

The Q10 value of an organism is its temperature coefficient- the factor of change in respiration caused by an increase in temperature of 10 °C. The value for P. periphylla, calculated in the range of 5°C - 10°C, was found to be 2.6. This value indicates that temperature affects the biochemical reactions of the organism. A value of 1 would mean that the organism is insensitive to temperature.

The water content of P. periphylla is 95.7 - 96.6 percent of the total wet weight. The measured salinity of the surrounding water when this was measured was 33.1-33.3 percent.

Periphylla periphylla are one of the only five scyphozoan species that is bioluminescent. The bioluminescence, along with with its red-brown coloring and the direction of its tentacles, make it easy to distinguish. The blue or blue-green light emission occurs as a result of stimulation and is concentrated in specific parts of the organism, such as the marginal lappets and near the coronal groove. Members of these species exhibit bioluminescence as a response to a short pulse of alternating current with a series of flashes.

Range length: 20 (high) cm.

Other Physical Features: ectothermic ; heterothermic ; radial symmetry ; venomous

Sexual Dimorphism: sexes alike

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Ecology

Habitat

in deep water
  • UNESCO-IOC Register of Marine Organisms
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Abyssopelagic
  • Census of Marine Zooplankton, 2006. NOAA Ship Ronald H Brown, deployment RHB0603, Sargasso Sea. Peter Wiebe, PI. Identifications by L. Bercial, N. Copley, A. Cornils, L. Devi, H. Hansen, R. Hopcroft, M. Kuriyama, H. Matsuura, D. Lindsay, L. Madin, F. Pagè
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Bathypelagic
  • Census of Marine Zooplankton, 2006. NOAA Ship Ronald H Brown, deployment RHB0603, Sargasso Sea. Peter Wiebe, PI. Identifications by L. Bercial, N. Copley, A. Cornils, L. Devi, H. Hansen, R. Hopcroft, M. Kuriyama, H. Matsuura, D. Lindsay, L. Madin, F. Pagè
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upper epipelagic
  • North-West Atlantic Ocean species (NWARMS)
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These members of the Class Scyphozoa live anywhere from the surface to 1000 meters deep in the ocean. At night, or when feeding, they may get closer to the surface. This vertical migration occurs particularly at latitudes farther from the equator, as is the case of medusae under ice in Antarctica. Much research has focused on the abundance of P. periphylla in Norwegian fjords, where the distribution follows a vertical layering pattern. Distribution also seems to be strongly affected by the location of food, as well as physical conditions. For example, P. periphylla may not approach the surface if strong winds result in turbulence.

Periphylla periphylla tends to live in deeper waters in subtropical and tropical regions. Depths vary with latitude, as it can live in shallow areas north of 42°N. This species likely submerges when it is closer to the equator due to the temperature of the water in the surface layer. Periphylla periphylla can survive temperatures up to 19.8 °C, although most specimens are collected at temperatures between 4 °C and 11 °C. There may be a connection between temperature tolerance, temerature-dependent metabolic rates, and food supply. Vertical mixing can also affect the jellyfish's submerging at a certain latitude.

The vertical location of these jellyfish is also linked to light intensity. The pigment that gives P. periphylla red-brown color can have a lethal affect when exposed to light. Since light intensity is based on depth, individuals tend to migrate to depths with relatively low light exposure.

Range depth: 1000 to surface m.

Average depth: 500 m.

Habitat Regions: temperate ; tropical ; polar ; saltwater or marine

Aquatic Biomes: pelagic

  • Arai, M. 1997. A Functional Biology of Scyphozoa. Boundary Row, London: Chapman & Hall.
  • Bamstedt, U., S. Kaartvedt, M. Youngbluth. 2003. An evaluation of acoustic and video methods to estimate the abundance and vertical distribution of jellyfish. Journal of Plankton Research, 25 (11): 1307-1318. Accessed April 27, 2011 at http://plankt.oxfordjournals.org/cgi/reprint/25/11/1307.
  • Jarms, G., H. Tiemann, U. Bamstedt. 2002. Development and biology of Periphylla periphylla (Scyphozoa: Coronatae) in a Norwegian fjord. Marine Biology, 141 (4): 647-657.
  • Kaartvedt, S., T. Klevjer, T. Torgersen, T. Sornes, A. Rostad. 2007. Diel vertical migration of individual jellyfish (Periphylla periphylla). Limnology and oceanography, 52 (3): 975-983. Accessed April 27, 2011 at http://222.aslo.org/lo/toc/vol_52/issue_3/0975.pdf.
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Depth range based on 307 specimens in 1 taxon.
Water temperature and chemistry ranges based on 272 samples.

Environmental ranges
  Depth range (m): 0 - 5316
  Temperature range (°C): -1.698 - 21.554
  Nitrate (umol/L): 0.156 - 44.379
  Salinity (PPS): 32.845 - 36.605
  Oxygen (ml/l): 0.303 - 8.070
  Phosphate (umol/l): 0.030 - 3.485
  Silicate (umol/l): 0.798 - 219.848

Graphical representation

Depth range (m): 0 - 5316

Temperature range (°C): -1.698 - 21.554

Nitrate (umol/L): 0.156 - 44.379

Salinity (PPS): 32.845 - 36.605

Oxygen (ml/l): 0.303 - 8.070

Phosphate (umol/l): 0.030 - 3.485

Silicate (umol/l): 0.798 - 219.848
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

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Trophic Strategy

Food Habits

Periphylla periphylla use tentacles to grasp their prey, and with the help of marginal lappets, bend them inwards to transfer the prey into the mouth of the individual. Some research has indicated that the location of prey has an effect on the movement of these medusae.

One of the earliest studies that was conducted on the diets of different scyphozoans included P. periphylla. Fourteen specimens contained food, and 100% of the prey were copepods, the majority being calanoid copepods. These medusae also feed on krill (such as Meganyctiphanes norvegica), a type of zooplankton, as well as chaetognaths and ostracods. They may also eat small fish and other medusae.

Animal Foods: fish; aquatic crustaceans; cnidarians; other marine invertebrates; zooplankton

Primary Diet: carnivore (Eats non-insect arthropods, Eats other marine invertebrates); planktivore

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Associations

Ecosystem Roles

Pelagic amphipods, genus Hyperia, live on, or even in, P. periphylla. It has not yet been determined if they are parasitic.

Periphylla periphylla are predators of copepods, krill, chaetognaths, and ostracods. They are also the prey of organisms such as Alepocephalus bairdii and Macrourus berglax.

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Predation

In the Northern Atlantic ocean, two common predators of P. periphylla at depths of below 1000 meters are Alepocephalus bairdii and Macrourus berglax. A third predator is the pelagic shrimp Notostomus robustus. Along with nematocysts, the bioluminescence could be a form of defense, as it may repel potential predators by signaling danger or distastefulness.  Anemones, such as Isotealia antarctica, are also potential predators, as well as sea spiders, if they are able to make contact with an individual.

Known Predators:

Anti-predator Adaptations: aposematic

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Life History and Behavior

Behavior

Communication and Perception

Periphylla periphylla are bioluminescent at all stages of life, and this bioluminescence may be used as a warning to predators. Periphylla periphylla react to light - it can be lethal to those mature individuals. Members of this species lack an acoustically sensitive organ (such as the gas bladder of fish) and react very little to sound. They also react to tactile stimulation, producing bioluminescent light that spreads from the point of stimulation to the nerve nets of the individual.

Communication Channels: visual

Other Communication Modes: photic/bioluminescent

Perception Channels: infrared/heat ; tactile ; chemical

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Behaviour

Like other members of the group Cnidaria - including corals and sea anemones - this jellyfish has stinging cells on its tentacles to attack prey. One stinging cell - the eurytele - is larger in Periphylla periphylla than in any other jellyfish.This species is known as a vertical migrator. It rises and falls in the water on a daily basis. At night it rises to shallower depths. Exposure to light results in fast downward-swimming, as this has a phototoxic effect on its pigment porphyrin.

Nutrition
This jellyfish feeds on crustacea, small fish and other medusae. There is evidence that it behaves as an active predator. It replaces fish in the food chain of Lurefjorden, where light conditions do not favour visual predators.
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Life Cycle

Development

Studies on live specimens obtained from Lurefjorden in Norway showed the life cycle of P. periphylla involves direct development from egg to young medusae, lacking a planula, polyp stage, and an ephyra stage.

The life cycle contains a total of 14 developmental stages. Stage 1, which can last anywhere from 1 to 10 days, are the eggs, which are relatively large, and at first are sessile and on average, do not live as deep as fully grown individuals. In Stage 2 (5-14 days in duration), the egg has flattened slightly in the middle. In stage 3, the first signs of the coronal groove can be seen. In Stage 4 (6-16 days in duration), wavy structures may be observed, as well as radial lines pointing toward what will become the mouth. This is also the stage in which the first movements occur. By Stage 5, marginal lappets will have appeared, and the coronal groove is clearly visible. The main feature of Stage 6 is the newly developed tentacle buds. In this stage, one may also see larger marginal lappets, and the organism will have started to regain a spherical shape. Bell pulsations allow it to swim. The pigment porphyrin increases during development, although it first becomes visible in Stage 7, when the mouth also forms. In Stage 8, the tentacles are the same length as the marginal lappets, and the central disc begins to flatten. Individuals resembling young medusa, begin feeding and are fully motile in Stage 9. At this stage, marginal lappets will be at least 0.9 mm long. The duration of development from Stage 1 to 9 is estimated to last 2-3 months.

Pigmentation develops in the tips of the twelve tentacles by Stage 10. The pigmentation continues to spread in Stage 11, and by Stage 12, the tentacles are completely pigmented. In Stage 13, the marginal lappets and the coronal furrow are pigmented, and the pigment continues to move towards the bell.

The final stage, Stage 14, is when the medusa is completely pigmented. In this stage gonads appear and sexual dimorphism can be observed, however, the process of sex determination is unknown. At the end of this stage, the individual is a fully mature medusa.

Members of this species are bioluminescent, exhibiting a blue fluorescence, during all stages of life.

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Life Expectancy

Lifespan/Longevity

Little is known about the lifespan of P. periphylla. However, individuals of this species may have relatively long lives compared to similar species, perhaps as much as several decades. Mortality might be slightly lower in Norwegian Fjords, where this species is abundant.  The life span of these jellyfish is also affected by light exposure, which may cause its pigments to have a lethal affect on the individual.

Due to the large geographic range of P. periphylla, factors such as local predation and food availability should be taken into account while determining regional lifespans. For example, in clear water, predators might be more likely to find medusae, so the average lifespan may be lower.

Periphylla periphylla are difficult to maintain and raise for long periods of time, which may explain why no data have been recorded regarding the longevity of these medusae in captivity.

Average lifespan

Status: wild:
30 years.

  • Jarms, G., U. Bamstedt, H. Tiemann, M. Martinussen, J. Fossa. 1999. The holopelagic life cycle of the deep-sea medusa Periphylla periphylla (Scyphozoa, Coronatae). Sarsia, 84: 55-65.
  • Sornes, T., A. Hosia, U. Bamstedt, D. Aksnes. 2008. Swimming and feeding in Periphylla periphylla (Scyphozoa, Coronatae). Marine Biology, 153: 653-659.
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Reproduction

While very little is known about the details of reproduction of P. periphylla, mating most likely occurs near the surface. One observation is that only mature individuals are found near the surface, whereas smaller, immature individuals tended to stay a little lower, even at night. Examination of these mature specimens revealed gonads with mature sperm or eggs (respective to the determined sex). Little is also known about the social structure of P. periphylla.

The life-cycle of P. periphylla does not depend on season, so at any one time, an individual may be at a different stage. Reproduction occurs year round.

Observers have also noted that patches of these medusae seem to be denser in water that have dust and foam, which might indicate that individuals take advantage of water movements in order to aggregate.

While there is little more conclusive knowledge about the mating behaviors of P. periphylla, observed behaviors are similar to those of Tripedalia cystophora and Carybdea sivickisi, whose individuals exhibit internal fertilization, achieved by the male holding the female until sperm is transferred. However, since it is now known that these individuals continuously spawn, it is possible that they exhibit external fertilization. In order to conclusively determine what occurs, further observations are required.

Mating System: polygynandrous (promiscuous)

Periphylla periphylla breeds year-round. Individuals of this species are either male or female, and they reproduce sexually. Very little is known about fertilization in this species, including whether external or internal fertilization occurs. The frequency of breeding has not been determined.

Individuals of this species undergo direct development, growing gradually in size throughout their 14 stages of development, from egg to sexual maturity. While the time from stage 1 to 9 is believed to be 2-3 months, the length of time until sexual maturation is still unknown.

Female members of this species continuously produce a few, relatively large, eggs over a long period of time. Upon maturation they spawn (release gametes) continuously.

One unique feature of P. periphylla that separates it from other species of the Order Coronatae is that the medusae have complete and fully developed follicles.

Breeding interval: The breeding interval of Periphylla periphylla is currently undetermined.

Breeding season: Periphylla periphylla breed year-round.

Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual

Observations of parental involvement of mature P. periphylla have not been made. Other scyphozoan species, however, do not display this behavior.

Parental Investment: no parental involvement

  • Arai, M. 1997. A Functional Biology of Scyphozoa. Boundary Row, London: Chapman & Hall.
  • Jarms, G., H. Tiemann, U. Bamstedt. 2002. Development and biology of Periphylla periphylla (Scyphozoa: Coronatae) in a Norwegian fjord. Marine Biology, 141 (4): 647-657.
  • Tiemann, H., G. Jarms. 2010. Organ-like gonads, complex oocyte formation, and long-term spawning in Periphylla periphylla (Cnidaria, Scyphozoa, Coronatae). Marine Biology, 157 (3): 527-535.
  • Tiemann, H., I. Sotje, B. Johnston, P. Flood, U. Bamstedt. 2009. Documentation of potential courtship-behaviour in Periphylla periphylla (Cnidaria: Scyphozoa). Journal of the Marine Biological Association of the United Kingdom, 89 (1): 63-66. Accessed April 27, 2011 at http://journals.cambridge.org/action/displayFulltext?type=1&fid=4249976&jid=MBI&volumeId=89&issueId=01&aid=4249968#.
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Molecular Biology and Genetics

Molecular Biology

Genomic DNA is available from 1 specimen with morphological vouchers housed at University of the Philippines-Diliman, Marine Science Institute
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Conservation

Conservation Status

Periphylla periphylla is not a species that is not considered to be threatened, and it does not appear in any animal conservation databases. Much of the research done on this species has been sparked by the abundance of these medusae in Norwegian fjords.

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

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Relevance to Humans and Ecosystems

Benefits

Economic Importance for Humans: Negative

The large abundance of P. periphylla in Norwegian fjords has impacted the local fishing industry, as they clog the nets used by fishermen. There have been no adverse effects of this species on humans reported in any other regions.

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Economic Importance for Humans: Positive

Due to their role as both predator and prey to other species, P. periphylla is part of several food webs, and it is possible that its presence is necessary to maintain the populations of its prey, and to the survival of its predators. This could, consequently, affect fishing industries. However, there are no well documented benefits that P. periphylla provide to humans.

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Wikipedia

Helmet jellyfish

The helmet jellyfish (Periphylla periphylla) is a luminescent, red-colored jellyfish of the deep sea, belonging to the order Coronatae of the phylum Cnidaria.

Reproductive cycle[edit]

P. periphylla represents an exception, very rarely found in the phylum Cnidaria: the medusae go through no polyp stage, thus presenting a "holopelagic" life cycle. The medusae strew fertilized eggs in open water and these develop directly into medusae, whose development rests entirely upon the egg's high yolk supply. The ephyra stage common among other jellyfish is not to be observed in P. periphylla.

Life style[edit]

The jellyfish is found in depths up to 7,000 m and is adapted to its dark environment. A weight of up to a ton per cubic centimeter presses upon the animals, which live in deep sea.

At night the helmet jellyfish leaves the depths and swims up toward its food, plankton. With full stomach it turns from the surface back to the depths. Other deep-sea inhabitants feed upon its faeces.[citation needed]

Description[edit]

Helmet jellyfish reach a body size of up to 30cm. They consist 90% of water, the rest being tissue and gelatinous mass, which give the animals their form. They light themselves from within by means of bioluminescence, the red flashes serving as a signal amongst themselves. Between their marginal lobes sit small sense bulbs, by which the helmet jelly can distinguish between light and dark; they have been observed to avoid light.

Distribution[edit]

The helmet jelly is found in every ocean of the world, as well as in the Norwegian fjords and in the Mediterranean Sea.

Current ecological problems[edit]

In many fjords of Norway the helmet jelly has proliferated since the 1970s. It has become a competitor of fish for food and is thereby also a threat for the fishing industry. These jellyfish should have been deprived of their own food basis by displacement by almost all other sea creatures, yet the medusae swarms still live.

The cause is being studied at this time by marine biologist Ulf Båmstedt. Also not far from Bergen, in the Lurefjord, helmet jellies have proliferated. The object is to find a possible explanation for the new mass development. The ecology and population dynamics will be investigated by Norwegian and American work groups. The ontogeny, in particular the development of pigmentation, luminescence, food absorption and sense capacity, will be researched in a Hamburg work group.

Bibliography[edit]

  • Jarms, G.; Tiemann, J.; Båmstedt, U (2002), "Development and Biology of Periphylla periphylla (Peron & Lesueur, 1809) (Scyphozoa, Coronatae) in a Norwegian Fjord", Marine Biology 141 (4): 647–657, doi:10.1007/s00227-002-0858-x 
  • Sornes, T.A.; Hosia, A.; Båmstedt, Ulf; Aksnes, D.L. (2008), "Swimming and feeding in Periphylla periphylla (Scyphozoa, Coronatae)", Marine Biology 153 (4): 653–659, doi:10.1007/s00227-007-0839-1 
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