It is abundant in both atlantic and pacific coastal waters. The name obelia means needle and is of greek origin. Obelia geniculata linnaeus, 1758 knotted thread hydroid, knotted thread hydroid. Fmib 38483 seaplume obelia growing upon seaweed fucus from life. Hydroid species of obelia 275 table 5 measurements of the hydroid stage of ohelia geniculata in xm sw england republic of south africa 1973. The medusa, or jellyfish, swim freely and reproduce sexually, releasing eggs and sperm. Elevated mound of tissue that expands or contracts to regulate size of mouth opening. The primary function of the medusa is sexual reproduction. Six species in the area, of which the medusae can not be separated sufficiently. Predatory feeding of the hydromedusae obelia geniculata and phialla quadrata predatory feeding of the hydromedusae obelia geniculata and phialla quadrata fulton, r wear, r. Obelia geniculata lineages form three different clades, unambiguously monophyletic in most of the phylogenies fig.
The many species of this genus are widely distributed throughout all the oceans and are typical of cnidarians, both in their morphology and their life cycle. A total of 440 base pairs bp of 16s rdna and 575 bp of coi were sequenced for all taxa genbank accession numbers ay530328ay530429. Obelia geniculata is readily distinguishable from other members of this genus by the structure of its stem. A number of potential pathogens of commercial aquaculture were identified. Populations of the colonial hydroid obelia geniculata in the white sea reproduce asexually by frustule formation. Spontaneous electrical potentials from obelia geniculata hydranths were recorded using finetipped suction electrodes. It forms a series of internodes that are zigzag in their arrangement, and it is jointed at each bend. Phylum cnidaria hydrozoa, obelia, polyp questions and. Electrical, mechanical or chemical kc1 stimuli produce similar luminescent flashing in obelia geniculata. Download fulltext pdf obelia cnidaria, hydrozoa, campanulariidae. The polyp asexually produces medusae, or jellyfish. Obelia, genus of invertebrate marine animals of the class hydrozoa phylum cnidaria. Phylogenetic relationships of proboscoida broch, 1910.
For the love of physics walter lewin may 16, 2011 duration. The number of medusae rarely exceeds 36 per m 3, and the average number varies every year from 0. If you didnt find an alternative name that you like better than obelia, try our name generator. Luminescent flashes in response to individual stimuli occur in bursts. Obelia is a genus of hydrozoans, a class of mainly marine and some freshwater animal species that have both polyp and medusa stages in their life cycle. Media in category obelia geniculata the following 14 files are in this category, out of 14 total. Video of sanctuary invertebrates this includes a variety of crustaceans, mollusks, jellies, echinoderms, and worms. The resulting fertilized eggs develop into larvae, which become new polyps. The genus, widely distributed in all the oceans, is represented by many species. Phylum cnidaria hydrozoa, obelia, polyp class hydrozoa anatomy of obelia polyp stage. Thus, a nonlocomotory species becomes locomotory and an overcrowding of individuals within a limited area is avoided and. A naturalists rambles on the devonshire coast page 87 5980749.
We estimate that there are at least 400 persons in the world having this name which is around 0. The obelia dichotoma medusa is a small hydromedusa with the bell diameter greater than its height. In this article we will discuss about the structure and locomotion of obelia. There are many questions associated with the understanding of the origin and regulation of bioluminescence. Reproduction of the colonial hydroid obelia geniculata l.
It allows you to go beyond the similarities of a name, which can provide a lot of inspiration. Cnidarian species flower garden banks national marine. The name obelia is ranked on the 93,033rd position of the most used names. Agassiz, 1862 obelia fusiformis agassiz obelia geniculata f. Obelia geniculata, neoturris pileata and the lions mane jellyfish cyanea capillata.
To these may be added the hydroid obelia geniculata. Trace amounts of calcium ion trigger the intramolecular oxidation of the chromophore, coelenterazine into coelenteramide and co2 with the concomitant emission of light. The colours have been added for clarity in distinguishing the parts. At first sight the periodicity is masked by the irregular breeding of colonies which are waveworn or much. Common and scientific names of aquatic invertebrates from the united states and canada. Obelia geniculata linnaeus, 1758 obelia geniculata. Obelia is dioecious as each medusa has reproductive organs of only one sex. Obelia medusa umbrella flat, with velum minute or lacking authorities differ. Obelia dichotoma obelia geniculata obelia longissima obelia bidentata. The number of medusae rarely exceeds 36 per m3, and the average number varies every year from 0.
The primary behavioural responses of the hydranths were observed and correlated with specific electrical potentials. This species is a excellent eater, and attacks its prey with a vengeance. Obelia is cosmopolitan in distribution, forming a whitish or lightbrown plantlike fur in the sea. More than 16 unbranched tentacles, all about the same size, are distributed evenly along the margin of the bell. The animal begins life as a polypa tentacled, stalklike form resembling a small sea anemone attached to the ocean bottom or some other solid surface. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Marlin the marine life information network a hydroid. Predatory feeding of the hydromedusae obelia geniculata. A total of 51 obelia geniculata hydroids were collected and sequenced from new zealand, japan, and four locations in the north atlantic massachusetts, new brunswick, iceland, and france. You also agree to give credit to carolina biological supply company by adding a.
The larva can swim from place to place with the help of cilia and, being aided by water current, it can travel a long distance. The small branched hydroid colony is found attached to rocks, stones, shells of animals or on large seaweeds and appears like a delicate whitish or light brownish furlike growth. Nearly flat with a central stomach and 4 saclike gonads at the end of the radial canals. Obelin from the bioluminescent marine hydroid obelia. Successive flashes within each burst show a constant shape. Mitochondrial evolution and phylogeography in the hydrozoan. Obelia is a genus of hydrozoans, a class of mainly marine and some freshwater animal species. The gonads testis or ovaries are four in number and lie on the subumbrella, below the radial canals, in the form of knobs. Obelia geniculata has a rather conical hydrothecae as opposed to bellshaped that is only slightly longer than wide, and has plain margins rather than cusped fig. Obelia belongs to the phylum cnidaria, which includes corals, sea anemones, jellyfish, and the freshwater hydra.
The obelia life cycle begins as polyp colonies containing hydranth and gonangium. I fed my new born spiderlings fruit flies, than when they reached 12 1. It means that it is relatively mediumlength, compared to the other names. The cdna is a 774 bp fragment containing two overlapping open reading frames, one of which contained 585 bp encoding a 195 amino acid polypeptide which obviously has the primary structure of the apoprotein of a calciumregulated photoprotein. World register of marine species obelia geniculata. Wear department of zoology victoria university of wellington private bag wellington new zealand institute of marine sciences university of north carolina 3407. Phylogenetic relationships of proboscoida broch, 1910 cnidaria. In hydroid colonies, the tentacled feeding zooids or hydranths are usually white, pink or violet white in obelia and in obelia the chitinous outer covering or perisarc often gives the colonies a yellowish colour. Obelia dichotoma is generally a colonial hydroid although occasionally is unbranched and solitary. What marine recruits go through in boot camp earning the title making marines on parris island duration.
Hydranth withdrawal also occurs upon electrical or mechanical stimulation. These 16 names were selected by our users that were looking for other names like obelia. Obeliamedusa umbrella flat, with velum minute or lacking authorities differ. They show intraclade distances ranging from 0 to 3. Pdf reproduction of the colonial hydroid obelia geniculata l. Obelia is a permanently fixed colony but the planula larvae it produces are free swimming. Campanulariidae all specimens except the polyp founder colonies matched by dna barcoding. There is no difference between the male and female medusae. Behavioural physiology of the colonial hydroid obelia.
Obelin precursor obelia geniculata knotted thread hydroid. Hydrozoa belongs to the phylum cnidaria, which are aquatic mainly marine organisms that are relatively simple in structure obelia is also called sea fur. The colonial form varies from being large, erect and loosely fanshaped or elongate up to 35 cm in height, to being short and either bushy or unbranched up to 5 cm in height. The gonangium reproduce asexually, releasing medusa. The size of medusae is smaller than reported from other regions. A key question underlying this thesis was why coelenterazine evolved as the most common marine luciferin. The regulation and origin of bioluminescence in the. I also give her one pinkiemouse or a house gecko twice a year for variety. Obelia longissima exhibits a typical leptolid life cycle consisting of a sessile colonial, vegetative hydroid stage, a freeliving sexual medusoid stage, and a planula larval stage. By downloading this image, you agree to abide by flickrs restrictions.
A microphagous, filterfeeding medusa article pdf available in marine ecology 28s1. Obelia the sea fur obelia is a marine colonial trimorphic hydrozoan having polyp, medusa and blastostyle stages in its life history. Obelia is a name thats been used by parents who are considering baby names for girls. Click on a link below to jump directly to a specific cnidarian. Towards the base of the hydrocaulus in the axils of the polyps, are reproductive polyps called blastostyles. Another problem addressed was the coelenterazine source of the bioluminescent hydroid obelia, which is unknown.