Journal articles: 'Phylum cnidaria'

1

Van Iten, Heyo. "Affinities and class-level systematics of the phylum Cnidaria." Paleontological Society Special Publications 6 (1992): 297. http://dx.doi.org/10.1017/s2475262200008571.

Full text

Abstract:

Phylogenetic relationships among the cnidarian classes Anthozoa, Hydrozoa and Scyphozoa, and between Cnidaria and other metazoan phyla, continue to be subject to widely divergent interpretations. Also controversial are the affinities of numerous fossil groups, including Byronia Bischoff, Sphenothallus Hall and conulariids, that have been interpreted as extinct cnidarians. Currently favored interpretations of evolution within Cnidaria are generally consistent with one of two alternative hypotheses of phylogenetic relationships: scyphozoans and anthozoans are members of a monophylclic group that excludes hydrozoans; or scyphozoans and hydrozoans are members of a monophyletic group that excludes anthozoans. Putative anthozoan-scyphozoan synapomorphies include (1) gastric septa present; (2) cnidae present in both ectoderm and gastroderm; (3) sex cells gastrodermal; and (4) mesoglea contains amoeboid cells. Putative hydrozoan-scyphozoan synapomorphies include (1) medusa present; (2) tetraradial symmetry; (3) rhopaloid nematocysts; and (4) similarities in sperm structure.Evaluation of alternative hypotheses of relationships within Cnidaria is complicated by uncertainty surrounding relationships between this and other metazoan phyla. While some investigators have interpreted Cnidaria and Ctenophora as members of a monophyletic group that excludes other phyla, others have argued that ctenophorans are more closely related to platyhelminths than they are to cnidarians. Putative cnidarian-ctenophoran synapomorphies include (1) production of cells modified for prey capture; and (2) presence of a medusa. Putative ctenophoran-platyhelminth synapomorphies include (1) presence of gonoducts; (2) ciliated cells with several to many cilia; (3) determinate cleavage; and (4) muscle cells developed from mesoderm. Comparisons of these and other phyla indicate that the strongest hypotheses of synapomorphy are those between cnidarians and ctenophorans. Ctenophorans do not have a mesoderm, and they lack complex reproductive structures that can be homologized with platyhelminth gonoducts. Similarities between ctenophorans and platyhelminths in ciliation and cleavage type are either non-homologous or shared primitive. The most recent common ancestor of ctenophorans and cnidarians was probably a medusa-like animal with circular and meridional muscle fibers and a non-septate digestive cavity having four radial canals. This cavity probably lacked cells specialized for prey capture, but glutinant prey-capture structures may have been present on tentacles. Sperm produced by this common ancestor were most similar to sperm of extant ctenophorans, hydrozoans and scyphozoans. Anatomical features unique to ctenophorans or cnidarians, regarded by some investigators as evidence against a close relationship between these two groups, are autapomorphies. These interpretations imply that putative hydrozoan-scyphozoan synapomorphies are actually shared primitive, and that the presence of gastric septa and cnidae-bearing gastric filaments in scyphozoans and anthozoans is shared derived. This would mean that the most parsimonious hypothesis of phylogenetic relationships within Cnidaria is that anthozoans and scyphozoans are members of a monophyletic group that excludes hydrozoans.Debate over relationships among these extant taxa has heightened interest in the affinities of prominent groups of problematic fossil cnidarians. Byronia Bischoff, Sphenothallus Hall and conulariids, all characterized by an apatitic, multilamellar theca, show detailed anatomical similarities to hydrozoans and/or scyphozoans. Putative synapomorphies linking Byronia and coronatid scyphozoans include the presence of multiple whorls of thorn-like nodes projecting into the thecal cavity, with each whorl consisting of eight nodes arranged in two sets of four nodes each. Sphenothallus, characterized by a pair of tentacles and, in some species, multiple branching, is most similar to hydrozoan and scyphozoan polyps, many of which are colonial or exhibit a single pair of tentacles early in their development. Similarities in hard- and soft-part anatomy between scyphozoans and conulariids suggest that conulariids, like scyphozoans, possessed four gastric septa and produced medusae through polydisc strobilation. Although conulariids have been interpreted as ancestral to extant cnidarians, they are more likely either a sister group to Scyphozoa or members of this class.

APA, Harvard, Vancouver, ISO, and other styles

2

DALY, MARYMEGAN, MERCER R. BRUGLER, PAULYN CARTWRIGHT, ALLEN G. COLLINS, MICHAEL N. DAWSON, DAPHNE G. FAUTIN, SCOTT C. FRANCE, et al. "The phylum Cnidaria: A review of phylogenetic patterns and diversity 300 years after Linnaeus*." Zootaxa 1668, no. 1 (December 21, 2007): 127–82. http://dx.doi.org/10.11646/zootaxa.1668.1.11.

Full text

Abstract:

Systema Naturae includes representatives of every major lineage of the animal phylum Cnidaria. However, Linnaeus did not classify the members of the phylum as is now done, and the diversity of the group is not well represented. We contrast the Linnaean perspective on cnidarian diversity with the modern, phylogenetic perspective. For each order, we detail diversity at the family level, providing phylogenetic context where possible.

APA, Harvard, Vancouver, ISO, and other styles

3

Stabili, Loredana, Maria Parisi, Daniela Parrinello, and Matteo Cammarata. "Cnidarian Interaction with Microbial Communities: From Aid to Animal’s Health to Rejection Responses." Marine Drugs 16, no. 9 (August 23, 2018): 296. http://dx.doi.org/10.3390/md16090296.

Full text

Abstract:

The phylum Cnidaria is an ancient branch in the tree of metazoans. Several species exert a remarkable longevity, suggesting the existence of a developed and consistent defense mechanism of the innate immunity capable to overcome the potential repeated exposure to microbial pathogenic agents. Increasing evidence indicates that the innate immune system in Cnidarians is not only involved in the disruption of harmful microorganisms, but also is crucial in structuring tissue-associated microbial communities that are essential components of the Cnidarian holobiont and useful to the animal’s health for several functions, including metabolism, immune defense, development, and behavior. Sometimes, the shifts in the normal microbiota may be used as “early” bio-indicators of both environmental changes and/or animal disease. Here the Cnidarians relationships with microbial communities and the potential biotechnological applications are summarized and discussed.

APA, Harvard, Vancouver, ISO, and other styles

4

Cartwright, Paulyn, and Annalise M. Nawrocki. "Character Evolution in Hydrozoa (phylum Cnidaria)." Integrative and Comparative Biology 50, no. 3 (July 9, 2010): 456–72. http://dx.doi.org/10.1093/icb/icq089.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Adachi, Kenta, Hiroshi Miyake, Takashi Kuramochi, Kanta Mizusawa, and Sei-ichi Okumura. "Genome size distribution in phylum Cnidaria." Fisheries Science 83, no. 1 (December 3, 2016): 107–12. http://dx.doi.org/10.1007/s12562-016-1050-4.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Fautin, Daphne Gail. "Reproduction of Cnidaria." Canadian Journal of Zoology 80, no. 10 (October 1, 2002): 1735–54. http://dx.doi.org/10.1139/z02-133.

Full text

Abstract:

Empirical and experimental data on cnidarian reproduction show it to be more variable than had been thought, and many patterns that had previously been deduced hold up poorly or not at all in light of additional data. The border between sexual and asexual reproduction appears to be faint. This may be due to analytical tools being insufficiently powerful to distinguish between the two, but it may be that a distinction between sexual and asexual reproduction is not very important biologically to cnidarians. Given the variety of modes by which it is now evident that asexual reproduction occurs, its ecological and evolutionary implications have probably been underestimated. Appropriate analytical frameworks and strategies must be developed for these morphologically simple animals, in which sexual reproduction may not be paramount, that during one lifetime may pass though two or more phases differing radically in morphology and ecology, that may hybridize, that are potentially extremely long-lived, and that may transmit through both sexual and asexual reproduction mutations arising in somatic tissue. In cnidarians, perhaps more than in any other phylum, reproductive attributes have been used to define taxa, but they do so at a variety of levels and not necessarily in the way they have conventionally been considered. At the species level, in Scleractinia, in which these features have been most studied, taxa defined on the basis of morphology, sexual reproduction, and molecular characters may not coincide; there are insufficient data to determine if this is true throughout the phylum. At the class level, transverse fission occurs in members of all three major taxa but is rare outside Scyphozoa, the group of which it is considered characteristic (pending more research, its absence in Cubozoa should be ascribed to poor knowledge). Understanding the role of transverse fission in the ecology and reproductive biology of hydrozoans and anthozoans could shed light on scyphozoan evolutionary history, and elucidating its morphogenesis in all groups is essential to determining if it is homologous across the classes. Only by comparing aspects of reproduction among cnidarians of various taxa will idiosyncratically adaptive strategies be distinguished from reproductive characters that reflect evolution and so are phylogenetically informative.

APA, Harvard, Vancouver, ISO, and other styles

7

Americus, Benjamin, Brett M. Austin, Tamar Lotan, Jerri L. Bartholomew, and Stephen D. Atkinson. "In vitro and in vivo assays reveal that cations affect nematocyst discharge in Myxobolus cerebralis (Cnidaria: Myxozoa)." Parasitology 147, no. 12 (July 14, 2020): 1352–58. http://dx.doi.org/10.1017/s0031182020001158.

Full text

Abstract:

AbstractMyxozoans are parasitic, microscopic cnidarians that have retained the phylum-characteristic stinging capsules called nematocysts. Free-living cnidarians, like jellyfish and corals, utilize nematocysts for feeding and defence, with discharge powered by osmotic energy. Myxozoans use nematocysts to anchor to their fish hosts in the first step of infection, however, the discharge mechanism is poorly understood. We used Myxobolus cerebralis, a pathogenic myxozoan parasite of salmonid fishes, and developed two assays to explore the nature of its nematocyst discharge. Using parasite actinospores, the infectious stage to fish, we stimulated discharge of the nematocysts with rainbow trout mucus in vitro, in solutions enriched with chloride salts of Na+, K+, Ca2+ and Gd3+, and quantified discharge using microscopy. We then used quantitative polymerase chain reaction to evaluate the in vivo effects of these treatments, plus Mg2+ and the common aquaculture disinfectant KMnO₄, on the ability of M. cerebralis actinospores to infect fish. We found that Mg2+ and Gd3+ reduced infection in vivo, whereas Na+ and K+ over-stimulated nematocyst discharge in vitro and reduced infection in vivo. These findings align with nematocyst discharge behaviour in free-living Cnidaria, and suggest phylum-wide commonalties, which could be exploited to develop novel approaches for controlling myxozoan diseases in aquaculture.

APA, Harvard, Vancouver, ISO, and other styles

8

Mokady, Ofer, and Leo W. Buss. "Transmission Genetics of Allorecognition in Hydractinia symbiolmgicarpus (Cnidaria: Hydrozoa)." Genetics 143, no. 2 (June 1, 1996): 823–27. http://dx.doi.org/10.1093/genetics/143.2.823.

Full text

Abstract:

Abstract Allorecognition is ubiquitous, or nearly so, amongst colonial invertebrates. Despite the prominent role that such phenomena have played both in evolutionary theory and in speculations on the origin of the vertebrate immune system, unambiguous data on the transmission genetics of fusibility (i.e., the ability of two individuals to fuse upon tissue contact) is lacking for any metazoan outside of the phylum Chordata. We have developed lines of the hydroid Hydractinia symbiolongzcarpus (Phylum Cnidaria) inbred for fusibility and here report results of breeding experiments establishing that fusibility segregates as expected for a single locus with codominantly expressed alleles, with one shared allele producing a fusible phenotype. Surveys of fusibility in field populations and additional breeding experiments indicate the presence of an extensive allele series.

APA, Harvard, Vancouver, ISO, and other styles

9

Kitchen, Sheila A., Camerron M. Crowder, Angela Z. Poole, Virginia M. Weis, and Eli Meyer. "De NovoAssembly and Characterization of Four Anthozoan (Phylum Cnidaria) Transcriptomes." G3: Genes|Genomes|Genetics 5, no. 11 (September 17, 2015): 2441–52. http://dx.doi.org/10.1534/g3.115.020164.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Atkinson, Stephen D., Jerri L. Bartholomew, and Tamar Lotan. "Myxozoans: Ancient metazoan parasites find a home in phylum Cnidaria." Zoology 129 (August 2018): 66–68. http://dx.doi.org/10.1016/j.zool.2018.06.005.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Inglis, WG. "Evolutionary Waves: Patterns in the Origins of Animal Phyla." Australian Journal of Zoology 33, no. 2 (1985): 153. http://dx.doi.org/10.1071/zo9850153.

Full text

Abstract:

Concordant patterns of embryology, morphology and functional anatomy delimit grades of animal phyla, each of which contains a 'Major Phylum': PARACOELOMATA (nom.nov.) = acoelomates + pseudocoelomates, flexible hydrostatic skeleton, Nematoda; DEUTEROSTOMIA (including lophophorates) = enterocoelic coelom, rigid internal skeleton, Chordata; and PROTOSTOMIA with two subgrades, MONOMERIC P. = unsegmented, single coelom, molluscan blastular cross, partial rigid exoskeleton, Molluscs; and POLYMERIC P. = segmented, multiple coelom, annelid cross, rigid exoskeleton, Uniramia. Such groups are usually treated as arbitrary stages in mono- and limited-branch phylogenies, but recent studies show them to be real and significant because the only phylogenetic links are from each Paracoelomata and Protostomia Phylum to Turbellaria; and each Deuterostomia Phylum to Cnidaria-Ctenophora and/or enteropneust Hemichordata. Similar grades have often been explained by hypothetical common ancestors, which are unnecessary if the phyla arose during 'evolutionary waves'. These attribute the origin of each grade to the likelihood that its constituent phyla arose independently, about the same time, from the same ciliary powered ancestral stock which was preadapted to enabling a potential body cavity to be actualized while evolving a cylindrical, wholly muscle-powered, body with a hydrostatic skeleton. Because such a skeleton is functionally dependent upon other structural modifications, particularly of the body wall, it could appear only when these were also available. If the latter could be supplied in a number of ways, all opportunities would be exploited and a body cavity would appear several times. The morphology suggests that this did happen, so that a pseudocoelom and coelom evolved independently in each phylum where they occur. Because of evidence that Protostomia and Deuterostomia were never linked during evolution, the origin of the coeloms in the former are explained by the Gonocoelic Theory and in the latter by the Enterocoelic. This, with the recognition of the monomeric protostomes as a distinct group, establishes that segmentation arose at the same time as the coeloms, so that their origins are one problem and not two as usually thought. Finally, protistan data suggest that Turbellaria, and so Paracoelomata and Protostomia, arose from 'close mitosis' flagellates, as did Fungi; while Cnidaria, and so Deuterostomia, arose from 'open mitosis' flagellates. as did Plantae. Thus, the classic Animalia division into Protostomia and Deuterostomia may represent a Protista division such that the animal groups are closer to fungi and plants respectively than they are to each other.

APA, Harvard, Vancouver, ISO, and other styles

12

Ruiz-Ramos, Dannise V., and Iliana B. Baums. "Microsatellite abundance across the Anthozoa and Hydrozoa in the phylum Cnidaria." BMC Genomics 15, no. 1 (2014): 939. http://dx.doi.org/10.1186/1471-2164-15-939.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Haddock, Steven H. D., Nadia Mastroianni, and Lynne M. Christianson. "A photoactivatable green-fluorescent protein from the phylum Ctenophora." Proceedings of the Royal Society B: Biological Sciences 277, no. 1685 (December 16, 2009): 1155–60. http://dx.doi.org/10.1098/rspb.2009.1774.

Full text

Abstract:

Genes for the family of green-fluorescent proteins (GFPs) have been found in more than 100 species of animals, with some species containing six or more copies producing a variety of colours. Thus far, however, these species have all been within three phyla: Cnidaria, Arthropoda and Chordata. We have discovered GFP-type fluorescent proteins in the phylum Ctenophora, the comb jellies. The ctenophore proteins share the x YG chromophore motif of all other characterized GFP-type proteins. These proteins exhibit the uncommon property of reversible photoactivation, in which fluorescent emission becomes brighter upon exposure to light, then gradually decays to a non-fluorescent state. In addition to providing potentially useful optical probes with novel properties, finding a fluorescent protein in one of the earliest diverging metazoans adds further support to the possibility that these genes are likely to occur throughout animals.

APA, Harvard, Vancouver, ISO, and other styles

14

Sendino, María C., and Patricio Domínguez. "Análisis documental de la distribución geográfica y estratigráfica de los conuláridos (Cnidaria) de Gondwana." Spanish Journal of Palaeontology 21, no. 2 (February 26, 2021): 175. http://dx.doi.org/10.7203/sjp.21.2.20489.

Full text

Abstract:

En este trabajo se sintetiza el registro estratigráfico de los conuláridos (Familia Conulariidae Walcott, 1886, Orden Conulariida Miller & Gurley, 1896, Phylum Cnidaria Hatschek, 1888) de Gondwana para mostrar la importancia estratigráfica de estos organismos fósiles. Se ha elaborado una base de datos documental que permite identificar los períodos y épocas en los que los conuláridos se diversifican más y en los que son más abundantes.

APA, Harvard, Vancouver, ISO, and other styles

15

Webers, Gerald F., and Ellis L. Yochelson. "A revision of Palaeacmaea (Upper Cambrian) (?Cnidaria)." Journal of Paleontology 73, no. 4 (July 1999): 598–607. http://dx.doi.org/10.1017/s002233600003242x.

Full text

Abstract:

Palaeacmaea typica, the type species of the genus, and P. irvingi, the only other Late Cambrian taxon considered congeneric are redescribed herein. Their morphology suggests that they are neither Monoplacophora, where they are currently assigned, nor are they Mollusca. Specimens of P. irvingi demonstrate considerable variation in shape, interpreted as distortion of a flexible integument, of essentially no thickness. A neotype is designated for P. irvingi; it is interpreted as a medusiform fossil, possibly a cnidarian. Only the holotype of P. typica is known, but it shows comparable features. The genus and the family Palaeacmaeide are placed in Phylum Incertae Sedis. Four Ordovician species previously assigned to Palaeacmaea, show none of the characteristics noted, and they are tentatively reassigned to other genera.

APA, Harvard, Vancouver, ISO, and other styles

16

Turk, Tom, and William R. Kem. "The phylum Cnidaria and investigations of its toxins and venoms until 1990." Toxicon 54, no. 8 (December 2009): 1031–37. http://dx.doi.org/10.1016/j.toxicon.2009.06.031.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Bridge, D., C. W. Cunningham, B. Schierwater, R. DeSalle, and L. W. Buss. "Class-level relationships in the phylum Cnidaria: evidence from mitochondrial genome structure." Proceedings of the National Academy of Sciences 89, no. 18 (September 15, 1992): 8750–53. http://dx.doi.org/10.1073/pnas.89.18.8750.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Evans, Nathaniel M., Alberto Lindner, Ekaterina V. Raikova, Allen G. Collins, and Paulyn Cartwright. "Phylogenetic placement of the enigmatic parasite, Polypodium hydriforme, within the Phylum Cnidaria." BMC Evolutionary Biology 8, no. 1 (2008): 139. http://dx.doi.org/10.1186/1471-2148-8-139.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Carreón-Palau, Laura, Nurgül Şen Özdemir, Christopher C. Parrish, and Camilla Parzanini. "Sterol Composition of Sponges, Cnidarians, Arthropods, Mollusks, and Echinoderms from the Deep Northwest Atlantic: A Comparison with Shallow Coastal Gulf of Mexico." Marine Drugs 18, no. 12 (November 27, 2020): 598. http://dx.doi.org/10.3390/md18120598.

Full text

Abstract:

Triterpenoid biosynthesis is generally anaerobic in bacteria and aerobic in Eukarya. The major class of triterpenoids in bacteria, the hopanoids, is different to that in Eukarya, the lanostanoids, and their 4,4,14-demethylated derivatives, sterols. In the deep sea, the prokaryotic contribution to primary productivity has been suggested to be higher because local environmental conditions prevent classic photosynthetic processes from occurring. Sterols have been used as trophic biomarkers because primary producers have different compositions, and they are incorporated in primary consumer tissues. In the present study, we inferred food supply to deep sea, sponges, cnidarians, mollusks, crustaceans, and echinoderms from euphotic zone production which is driven by phytoplankton eukaryotic autotrophy. Sterol composition was obtained by gas chromatography and mass spectrometry. Moreover, we compared the sterol composition of three phyla (i.e., Porifera, Cnidaria, and Echinodermata) collected between a deep and cold-water region and a shallow tropical area. We hypothesized that the sterol composition of shallow tropical benthic organisms would better reflect their photoautotrophic sources independently of the taxonomy. Shallow tropical sponges and cnidarians from environments showed plant and zooxanthellae sterols in their tissues, while their deep-sea counterparts showed phytoplankton and zooplankton sterols. In contrast, echinoids, a class of echinoderms, the most complex phylum along with hemichordates and chordates (deuterostomes), did not show significant differences in their sterol profile, suggesting that cholesterol synthesis is present in deuterostomes other than chordates.

APA, Harvard, Vancouver, ISO, and other styles

20

Evans, Nathaniel M., Alberto Lindner, Ekaterina V. Raikova, Allen G. Collins, and Paulyn Cartwright. "Correction: Phylogenetic placement of the enigmatic parasite, Polypodium hydriforme, within the Phylum Cnidaria." BMC Evolutionary Biology 9, no. 1 (2009): 165. http://dx.doi.org/10.1186/1471-2148-9-165.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Siddall, Mark E., Donald S. Martin, Diane Bridge, Sherwin S. Desser, and David K. Cone. "The Demise of a Phylum of Protists: Phylogeny of Myxozoa and Other Parasitic Cnidaria." Journal of Parasitology 81, no. 6 (December 1995): 961. http://dx.doi.org/10.2307/3284049.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Berntson, Ewann A., Scott C. France, and Lauren S. Mullineaux. "Phylogenetic Relationships within the Class Anthozoa (Phylum Cnidaria) Based on Nuclear 18S rDNA Sequences." Molecular Phylogenetics and Evolution 13, no. 2 (November 1999): 417–33. http://dx.doi.org/10.1006/mpev.1999.0649.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

J., Won, Rho B., and Song J. "A phylogenetic study of the Anthozoa (phylum Cnidaria) based on morphological and molecular characters." Coral Reefs 20, no. 1 (August 1, 2001): 39–50. http://dx.doi.org/10.1007/s003380000132.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Schlesinger, Ami, Eliahu Zlotkin, Esti Kramarsky-Winter, and Y. Loya. "Cnidarian internal stinging mechanism." Proceedings of the Royal Society B: Biological Sciences 276, no. 1659 (December 9, 2008): 1063–67. http://dx.doi.org/10.1098/rspb.2008.1586.

Full text

Abstract:

Stinging mechanisms generally deliver venomous compounds to external targets. However, nematocysts, the microscopic stinging organelles that are common to all members of the phylum Cnidaria, occur and act in both external and internal tissue structures. This is the first report of such an internal piercing mechanism. This mechanism identifies prey items within the body cavity of the sea anemone and actively injects them with cytolytic venom compounds. Internal tissues isolated from sea anemones caused the degradation of live Artemia salina nauplii in vitro . When examined, the nauplii were found to be pierced by discharged nematocysts. This phenomenon is suggested to aid digestive phagocytic processes in a predator otherwise lacking the means to masticate its prey.

APA, Harvard, Vancouver, ISO, and other styles

25

Van Iten, Heyo, Juliana de Moraes Leme, Marcello Guimarães Simões, Antonio Carlos Marques, and Allen G. Collins. "Reassessment of the phylogenetic position of conulariids (?Ediacaran‐Triassic) within the subphylum medusozoa (phylum cnidaria)." Journal of Systematic Palaeontology 4, no. 2 (January 2006): 109–18. http://dx.doi.org/10.1017/s1477201905001793.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Sanders, Steven M., Mariya Shcheglovitova, and Paulyn Cartwright. "Differential gene expression between functionally specialized polyps of the colonial hydrozoan Hydractinia symbiolongicarpus (Phylum Cnidaria)." BMC Genomics 15, no. 1 (2014): 406. http://dx.doi.org/10.1186/1471-2164-15-406.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Eppard, Robin A., Gregory J. Highison, and Robert W. Mead. "Scanning electron microscopy of epithelial surfaces of the sea anemoneAcontiophorum niveum (Phylum Cnidaria): Class anthozoa." Journal of Morphology 200, no. 1 (April 1989): 63–69. http://dx.doi.org/10.1002/jmor.1052000108.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Miglietta, Maria Pia, Davide Maggioni, and Yui Matsumoto. "Phylogenetics and species delimitation of two hydrozoa (phylum Cnidaria): Turritopsis (McCrady, 1857) and Pennaria (Goldfuss, 1820)." Marine Biodiversity 49, no. 3 (April 27, 2018): 1085–100. http://dx.doi.org/10.1007/s12526-018-0891-8.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Clavel, Damien, Guillaume Gotthard, David von Stetten, Daniele De Sanctis, Hélène Pasquier, Gerard G. Lambert, Nathan C. Shaner, and Antoine Royant. "Structural analysis of the bright monomeric yellow-green fluorescent protein mNeonGreen obtained by directed evolution." Acta Crystallographica Section D Structural Biology 72, no. 12 (November 30, 2016): 1298–307. http://dx.doi.org/10.1107/s2059798316018623.

Full text

Abstract:

Until recently, genes coding for homologues of the autofluorescent protein GFP had only been identified in marine organisms from the phyla Cnidaria and Arthropoda. New fluorescent-protein genes have now been found in the phylum Chordata, coding for particularly bright oligomeric fluorescent proteins such as the tetrameric yellow fluorescent proteinlanYFP fromBranchiostoma lanceolatum. A successful monomerization attempt led to the development of the bright yellow-green fluorescent protein mNeonGreen. The structures oflanYFP and mNeonGreen have been determined and compared in order to rationalize the directed evolution process leading from a bright, tetrameric to a still bright, monomeric fluorescent protein. An unusual discolouration of crystals of mNeonGreen was observed after X-ray data collection, which was investigated using a combination of X-ray crystallography and UV–visible absorption and Raman spectroscopies, revealing the effects of specific radiation damage in the chromophore cavity. It is shown that X-rays rapidly lead to the protonation of the phenolate O atom of the chromophore and to the loss of its planarity at the methylene bridge.

APA, Harvard, Vancouver, ISO, and other styles

30

Alzugaray, María Eugenia, María Victoria Gavazzi, and Jorge Rafael Ronderos. "Calcium signalling in early divergence of Metazoa: mechanisms involved in the control of muscle-like cell contraction in Hydra plagiodesmica." Canadian Journal of Zoology 97, no. 9 (September 2019): 812–24. http://dx.doi.org/10.1139/cjz-2018-0295.

Full text

Abstract:

Our laboratory has previously examined the effect of neuropeptides on the activity of the hypostome of the hydra Hydra plagiodesmica Dioni, 1968 (Cnidaria: Hydrozoa). These results showed that the hypostome, a structure extruded during feeding, responds to myoregulatory peptides and that this mechanism might be regulated by changes in the cytosolic levels of calcium (Ca2+). We analyse now the ways in which Ca2+ modulates hypostome activity during feeding. The use of calcium chelators confirms that Ca2+ is relevant in inducing hypostome extrusion. The assay of compounds that modulate the activity of Ca2+ channels in the endoplasmic reticulum suggests that, beyond the extracellular influx of calcium, intracellular sources of the ion are involved and might include both ryanodine receptors (RyR) and the inositol 1,4,5-trisphosphate receptor (IP3R). Bioinformatic searches based on sequences of RyR and IP3R of humans (Homo sapiens Linnaeus, 1758) show that IP3Rs are present in all groups analysed, including Fungi and Choanoflagellata. Although H. plagiodesmica responds to caffeine and ryanodine, which are known to modulate RyRs, this family of receptors seems not to be predicted in Cnidaria, suggesting that this phylum either lacks these kinds of channels or that they possess a different structure compared with those possessed by other Metazoa.

APA, Harvard, Vancouver, ISO, and other styles

31

Beagley, C. Timothy, Ronald Okimoto, and David R. Wolstenholme. "The Mitochondrial Genome of the Sea Anemone Metridium senile (Cnidaria): Introns, a Paucity of tRNA Genes, and a Near-Standard Genetic Code." Genetics 148, no. 3 (March 1, 1998): 1091–108. http://dx.doi.org/10.1093/genetics/148.3.1091.

Full text

Abstract:

Abstract The circular, 17,443 nucleotide-pair mitochondrial (mt) DNA molecule of the sea anemone, Metridium senile (class Anthozoa, phylum Cnidaria) is presented. This molecule contains genes for 13 energy pathway proteins and two ribosomal (r) RNAs but, relative to other metazoan mtDNAs, has two unique features: only two transfer RNAs (tRNAf-Met and tRNATrp) are encoded, and the cytochrome c oxidase subunit I (COI) and NADH dehydrogenase subunit 5 (ND5) genes each include a group I intron. The COI intron encodes a putative homing endonuclease, and the ND5 intron contains the molecule's ND1 and ND3 genes. Most of the unusual characteristics of other metazoan mtDNAs are not found in M. senile mtDNA: unorthodox translation initiation codons and partial translation termination codons are absent, the use of TGA to specify tryptophan is the only genetic code modification, and both encoded tRNAs have primary and secondary structures closely resembling those of standard tRNAs. Also, with regard to size and secondary structure potential, the mt-s-rRNA and mt-l-rRNA have the least deviation from Escherichia coli 16S and 23S rRNAs of all known metazoan mt-rRNAs. These observations indicate that most of the genetic variations previously reported in metazoan mtDNAs developed after Cnidaria diverged from the common ancestral line of all other Metazoa.

APA, Harvard, Vancouver, ISO, and other styles

32

Ashwood, Lauren M., Raymond S. Norton, Eivind A. B. Undheim, David A. Hurwood, and Peter J. Prentis. "Characterising Functional Venom Profiles of Anthozoans and Medusozoans within Their Ecological Context." Marine Drugs 18, no. 4 (April 9, 2020): 202. http://dx.doi.org/10.3390/md18040202.

Full text

Abstract:

This review examines the current state of knowledge regarding toxins from anthozoans (sea anemones, coral, zoanthids, corallimorphs, sea pens and tube anemones). We provide an overview of venom from phylum Cnidaria and review the diversity of venom composition between the two major clades (Medusozoa and Anthozoa). We highlight that the functional and ecological context of venom has implications for the temporal and spatial expression of protein and peptide toxins within class Anthozoa. Understanding the nuances in the regulation of venom arsenals has been made possible by recent advances in analytical technologies that allow characterisation of the spatial distributions of toxins. Furthermore, anthozoans are unique in that ecological roles can be assigned using tissue expression data, thereby circumventing some of the challenges related to pharmacological screening.

APA, Harvard, Vancouver, ISO, and other styles

33

Beazley, Lindsay I., and Ellen L. Kenchington. "Reproductive biology of the deep-water coral Acanella arbuscula (Phylum Cnidaria: Class Anthozoa: Order Alcyonacea), northwest Atlantic." Deep Sea Research Part I: Oceanographic Research Papers 68 (October 2012): 92–104. http://dx.doi.org/10.1016/j.dsr.2012.05.013.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Dorado, Edgar, and Cristina Cedeño. "Copepods, hydromedusae and siphonophores: Diversity and distribution in the Gerlache Strait, Antarctic Peninsula." Boletín de Investigaciones Marinas y Costeras 50, SuplEsp (May 26, 2021): 169–86. http://dx.doi.org/10.25268/bimc.invemar.2021.50.suplesp.942.

Full text

Abstract:

Project Biodiversity and oceanographic conditions of the strait of Gerlache “Biogerlache-Antarctica”, aims to carry out the characterization of the Antarctic fauna of the strait, generating new contributions to the biological inventories of Antarctica. Present work focuses on the biodiversity of the zooplanktonic community, specifically on copepods, hydromedusae and siphonophorae collected during the III Antarctic Expedition of Colombia “Admiral Padilla” (2016-2017). Sampling was carried out in seven oceanographic stations located along the Gerlache strait, with vertical trawls between the maximum depth of the station and the surface. 4100 organisms belonging to 38 species of the phylum Arthropoda (Orders Calanoid and Cyclopoid) and 10 species of the phylum Cnidaria (Subclasses Hydroidolina and Trachylina) were identified. Copepods families with the greatest richness of genera are Aetideidae and Metridinidae, with Metridia gerlachei, Chiridius polaris and Gaetanus tenuispinosus being frequent species in more than 50 % of the stations. Identified species are common to the Antarctic Peninsula (Bellingshausen Sea, Scotia Sea and the Weddell Sea), also the range of four copepods are extended for the epipelagic and mesopelagic waters of the Gerlache Strait. Other frequent species are the hydromedusae Arctapodema sp. and Solmundella bitentaculata and the siphonophores Dimophyes arctica and Diphyes antarctica, the latter being collected in both polygastric and eudoxic forms (the dominant form in all stations).

APA, Harvard, Vancouver, ISO, and other styles

35

DE LA CRUZ FRANCISCO, VICENCIO, and Ángel Eduardo Bandala-Pérez. "ESPONJAS Y CNIDARIOS (HYDROZOA Y ANTHOZOA) DEL ARRECIFE ORO VERDE; COBERTURA BENTÓNICA Y AFINIDAD FAUNÍSTICA CON SISTEMAS ARRECIFALES DE VERACRUZ, MÉXICO." CICIMAR Oceánides 31, no. 2 (December 9, 2016): 45. http://dx.doi.org/10.37543/oceanides.v31i2.185.

Full text

Abstract:

RESUMEN. Durante el periodo junio-agosto de 2015, se realizaron muestreos en 12 puntos geográficos del arrecife Oro Verde para explorar las porciones norte, sur, centro, este y oeste, con la finalidad de registrar especies de esponjas, hidrocorales y antozoos, así como para estimar la cobertura de algas, esponjas, corales, gorgonias y de componentes abióticos (e. g., arena y pavimento) mediante fototransectos de 50 m de longitud. Con esta información se realizaron análisis de escalamiento multidimensional no métrico (NMDS) para explicar similitudes de las unidades de muestreo. Además, se comparó la composición de esponjas y corales del arrecife Oro Verde con los demás sistemas arrecifales de Veracruz a fin de determinar afinidades mediante el método NMDS; para explicar diferencias significativas entre grupos disimiles se utilizó la prueba de similitud ANOSIM. Se registraron un total de 37 especies del Phylum Porifera y 29 especies del Phylum Cnidaria. Las especies con mayor frecuencia en el arrecife fueron las esponjas Callyspongia armigera, Niphates erecta y Amphimedon compressa, y los corales Montastraea cavernosa, Porites astreoides, Siderastrea sidérea y Colpophyllia natans. En cuanto a cobertura, las algas filamentosas y frondosas fueron las más abundantes (49.4±7.7% y 20±9.7%, respectivamente); con respecto a los corales que presentaron baja cobertura (9.5±6.1%), se identificaron principalmente M. cavernosa, C. natans y S. siderea. La riqueza faunística y la cobertura bentónica se distribuyen de manera homogénea en el arrecife, dado que los lugares de muestreo manifestaron semejanzas en estos atributos comunitarios. La composición de esponjas del arrecife Oro Verde presentó mayor afinidad con los arrecifes aledaños y con los arrecifes sumergidos del sur de Veracruz; en cambio, en cuanto a la riqueza de corales, el arrecife Oro Verde es más semejante con los arrecifes colindantes. Las discrepancias con los demás arrecifes se atribuyen a la falta de inventarios completos (e. g., Tuxpan) y/o por presentar especies con limitada distribución.Sponges and cnidarians (Hydrozoa and Anthozoa) from Oro Verde reef; benthic coverage and faunal affinity with the reef systems of Veracruz, MexicoABSTRACT. Sampling was conducted in twelve geographical points of the Oro Verde reef during the June-August 2015 period, in-order-to record species of sponges, hydrocorals and anthozoans, and to estimate the coverage of algae, sponges, corals, sea fans and abiotic components (e.g., sand and pavement) using 50 m long photo transects. We explored the northern, southern, central, eastern and western section of the reef. Analysis of non-metric multidimensional scaling (NMDS) was performed to explain similarities of the sampling units based on the information obtained. In addition, the composition of sponges and coral reefs from Oro Verde reef was compared with the other reef systems of Veracruz to determine affinities using the NMDS method. The similarity test ANOSIM was used to explain significant differences among dissimilar groups. A total of 37 species of Phylum Porifera and 29 species of Phylum Cnidaria were recorded. The most common species in the reef were the sponges Callyspongia armigera, Niphates erecta, and Amphimedon compressa, and the corals Montastraea cavernosa, Porites astreoides, Siderastrea siderea, Colpophyllia natans. Filamentous and frondose algae were the most abundant in coverage (49.4 ± 7.7% and 20 ± 9.7%, respectively), compared to reef corals that showed low coverage (9.5 ± 6.1%), which consisted mainly of M. cavernosa, C. natans and S. siderea. The faunal richness and the benthic coverage are distributed in a homogeneous way in the reef as sampling sites revealed similarities in these community attributes. The composition of sponges from Oro Verde reef presented higher affinity with the adjacent reefs and with the submerged reefs of southern of Veracruz. However, Oro Verde reef is more similar with neighboring reefs in species richness of corals. Discrepancies with the other reefs are attributed to the lack of complete inventories (e. g., Tuxpan) and / or by presenting species with limited distribution.

APA, Harvard, Vancouver, ISO, and other styles

36

van der Burg, Chloé A., and Peter J. Prentis. "The Tentacular Spectacular: Evolution of Regeneration in Sea Anemones." Genes 12, no. 7 (July 14, 2021): 1072. http://dx.doi.org/10.3390/genes12071072.

Full text

Abstract:

Sea anemones vary immensely in life history strategies, environmental niches and their ability to regenerate. While the sea anemone Nematostella vectensis is the starlet of many key regeneration studies, recent work is emerging on the diverse regeneration strategies employed by other sea anemones. This manuscript will explore current molecular mechanisms of regeneration employed by non-model sea anemones Exaiptasia diaphana (an emerging model species for coral symbiosis studies) and Calliactis polypus (a less well-studied species) and examine how these species compare to the model sea anemone N. vectensis. We summarize the field of regeneration within sea anemones, within the greater context of phylum Cnidaria and in other invertebrate models of regeneration. We also address the current knowledge on two key systems that may be implemented in regeneration: the innate immune system and developmental pathways, including future aspects of work and current limitations.

APA, Harvard, Vancouver, ISO, and other styles

37

Deguchi, Ryusaku, Eri Kondoh, and Junko Itoh. "Spatiotemporal characteristics and mechanisms of intracellular Ca2+ increases at fertilization in eggs of jellyfish (Phylum Cnidaria, Class Hydrozoa)." Developmental Biology 279, no. 2 (March 2005): 291–307. http://dx.doi.org/10.1016/j.ydbio.2004.11.036.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Heffernan, Linda M., and Gary W. Winston. "Spectral analysis and catalytic activities of the microsomal mixed-function oxidase system of the sea anemone (phylum: Cnidaria)." Comparative Biochemistry and Physiology Part C: Pharmacology, Toxicology and Endocrinology 121, no. 1-3 (November 1998): 371–83. http://dx.doi.org/10.1016/s0742-8413(98)10038-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

Folino-Rorem, Nadine C., and Corbin J. Renken. "Effects of salinity on the growth and morphology of the invasive, euryhaline hydroid Cordylophora (Phylum Cnidaria, Class Hydrozoa)." Invertebrate Biology 137, no. 1 (February 26, 2018): 78–90. http://dx.doi.org/10.1111/ivb.12207.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Pikesley, Stephen K., Brendan J. Godley, Sue Ranger, Peter B. Richardson, and Matthew J. Witt. "Cnidaria in UK coastal waters: description of spatio-temporal patterns and inter-annual variability." Journal of the Marine Biological Association of the United Kingdom 94, no. 7 (June 4, 2014): 1401–8. http://dx.doi.org/10.1017/s0025315414000137.

Full text

Abstract:

Concern has been expressed over future biogeographical expansion and habitat capitalization by species of the phylum Cnidaria, as this may have negative implications on human activities and ecosystems. There is, however, a paucity of knowledge and understanding of jellyfish ecology, in particular species distribution and seasonality. Recent studies in the UK have principally focused on the Celtic, Irish and North Seas, but all in isolation. In this study we analyse data from a publicly-driven sightings scheme across UK coastal waters (2003–2011; 9 years), with the aim of increasing knowledge on spatial and temporal patterns and trends. We describe inter-annual variability, seasonality and patterns of spatial distribution, and compare these with existing historic literature. Although incidentally-collected data lack quantification of effort, we suggest that with appropriate data management and interpretation, publicly-driven, citizen-science-based, recording schemes can provide for large-scale (spatial and temporal) coverage that would otherwise be logistically and financially unattainable. These schemes may also contribute to baseline data from which future changes in patterns or trends might be identified. We further suggest that findings from such schemes may be strengthened by the inclusion of some element of effort-corrected data collection.

APA, Harvard, Vancouver, ISO, and other styles

41

Buss, Leo W., and Adolf Seilacher. "The Phylum Vendobionta: a sister group of the Eumetazoa?" Paleobiology 20, no. 1 (1994): 1–4. http://dx.doi.org/10.1017/s0094837300011088.

Full text

Abstract:

We offer an alternative interpretation of the Kingdom Vendobionta as a monophyletic sister group to the Eumetazoa. We hypothesize that the Vendobionta are cnidarian-like organisms that lacked cnidae. Cnidarians are held to have arisen by acquisition of cnidae by symbiosis with a microsporidian. Our analysis differs from existing interpretations of the Ediacaran fossils as ancestors of extant cnidarians in that we do not regard any of these forms as either polypoid or medusoid. This interpretation requires the erection of a new metazoan phylum, the Vendobionta.

APA, Harvard, Vancouver, ISO, and other styles

42

Chintiroglou, Chariton C., and Panagiotis Karalis. "Biometric investigations on the cnidae of the Aegean colour morphs of Anemonia viridis." Journal of the Marine Biological Association of the United Kingdom 80, no. 3 (June 2000): 543–44. http://dx.doi.org/10.1017/s0025315400002241.

Full text

Abstract:

The sea anemone Anemonia viridis is one of the most common species of the North Aegean Sea. The variety in colour morphs exhibited by this species, causes problems to taxonomy and ecology, and suggests that A. viridis should be subdivided into two distinct species according to the colour of the individuals. The approach used in this study was based on the biometrical cnidae characteristics of the two colour morphs (rustica and smaragdina), as it is known that cnidae biometry has been used as a taxonomic tool for the phylum Cnidaria. More than 20,000 nematocysts were measured to try and find a correlation between these measurements and some body parameters indicative of the maturity grade of the individuals, as potential taxonomic characteristics. Stable cnidae characteristics of the two different colour morphs were compared. However, they differed only in the biometry of the tentacles' a-basitrichs. This slight difference does not support the proposal to subdivide Anemonia viridis into two different species.

APA, Harvard, Vancouver, ISO, and other styles

43

Parisi, Maria Giovanna, Daniela Parrinello, Loredana Stabili, and Matteo Cammarata. "Cnidarian Immunity and the Repertoire of Defense Mechanisms in Anthozoans." Biology 9, no. 9 (September 11, 2020): 283. http://dx.doi.org/10.3390/biology9090283.

Full text

Abstract:

Anthozoa is the most specious class of the phylum Cnidaria that is phylogenetically basal within the Metazoa. It is an interesting group for studying the evolution of mutualisms and immunity, for despite their morphological simplicity, Anthozoans are unexpectedly immunologically complex, with large genomes and gene families similar to those of the Bilateria. Evidence indicates that the Anthozoan innate immune system is not only involved in the disruption of harmful microorganisms, but is also crucial in structuring tissue-associated microbial communities that are essential components of the cnidarian holobiont and useful to the animal’s health for several functions including metabolism, immune defense, development, and behavior. Here, we report on the current state of the art of Anthozoan immunity. Like other invertebrates, Anthozoans possess immune mechanisms based on self/non-self-recognition. Although lacking adaptive immunity, they use a diverse repertoire of immune receptor signaling pathways (PRRs) to recognize a broad array of conserved microorganism-associated molecular patterns (MAMP). The intracellular signaling cascades lead to gene transcription up to endpoints of release of molecules that kill the pathogens, defend the self by maintaining homeostasis, and modulate the wound repair process. The cells play a fundamental role in immunity, as they display phagocytic activities and secrete mucus, which acts as a physicochemical barrier preventing or slowing down the proliferation of potential invaders. Finally, we describe the current state of knowledge of some immune effectors in Anthozoan species, including the potential role of toxins and the inflammatory response in the Mediterranean Anthozoan Anemonia viridis following injection of various foreign particles differing in type and dimensions, including pathogenetic bacteria.

APA, Harvard, Vancouver, ISO, and other styles

44

W.O., Wan Maznah, Nur ‘Ain Kassim, and Zubir Din. "Zooplankton Community Structure in Relation to the Water Quality and Seston Fatty Acid Content in the Coastal Waters of Penang, Malaysia." Sains Malaysiana 50, no. 6 (June 30, 2021): 1577–88. http://dx.doi.org/10.17576/jsm-2021-5006-06.

Full text

Abstract:

Zooplankton community structure and seston fatty acid content in relation with water quality characteristics at selected sampling stations of Penang coastal waters were determined. Water and zooplankton samples were collected on five sampling occasions from July 2009 until April 2011. Zooplankton samples were collected by horizontal towing with plankton net (WP-2) and a fraction of the samples was used to get seston population for fatty acid analysis. Phylum Arthropoda dominated the sampling area with 78.80% of relative abundance, where Copepoda was the most abundant. Other phyla such as Chordata (9.10%), Cycliophora (6.12%), Actinopoda (2.08%), Rotifera (2.57%), Annelida (0.63%), Cnidaria (0.51%), and Chaetognatha (0.19%) were accounted in small abundance. Kuala Juru Station, which was highly impacted by human activities had the highest relative abundance and Jerejak Station (control station and considered to have low impact by anthropogenic activities) had the lowest relative abundance. Zooplankton diversity was quite low at all stations, might be due to large abundance of dominant taxa. The dominant fatty acid methyl esters (FAMEs) detected on seston consisted of SAFA (C16:0, C14:0, and C18:0), MUFA (C16:0, C14:0, and C18:0), PUFA (C18:2n6c and C20:5n3) and HUFA (C22:6n3 or DHA). Zooplankton community was influenced by food availability (phytoplankton, as measured by chlorophyll a and fatty acid composition in seston) and water quality.

APA, Harvard, Vancouver, ISO, and other styles

45

Van Iten, Heyo, Antonio C. Marques, Juliana de Moraes Leme, Mirian L. A. Forancelli Pacheco, and Marcello Guimaraes Simões. "Origin and early diversification of the phylum Cnidaria Verrill: major developments in the analysis of the taxon's Proterozoic-Cambrian history." Palaeontology 57, no. 4 (May 21, 2014): 677–90. http://dx.doi.org/10.1111/pala.12116.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Peter, S., B. Manojkumar, D. Pillai, A. Velusamy, B. Kamarudeen, P. Sreeparvathy, and F. Agnes. "Distribution and Diversity of Gelatinous Zooplankton in the South Eastern Arabian Sea, Kanyakumari to off Kollam." Vestnik Zoologii 52, no. 5 (October 1, 2018): 379–88. http://dx.doi.org/10.2478/vzoo-2018-0040.

Full text

Abstract:

Abstract An attempt was made out to study the distribution and diversity of gelatinous zooplankton in the South Eastern Arabian Sea in the region Kanyakumari to off Kollam. A total of 19 species belonging to 8 groups such as chaetognaths, siphonophores, Hydrozoa and Scyphozoa of the phylum Cnidaria, ctenophores, appendicularians, doliolids and salps were recorded. Chaetognaths were not only predominant group, but also the most numerous. Sagitta enfl ata was the most widely distributed chaetognath species from most of the stations studied. Th e siphonophores were the second most abundant group. Shannon-Weaver species diversity index (H′), Margalef’s species diversity index (D) and Pielou’s species evenness (J′) of gelatinous zooplankton were found to be higher from the off shore, Kollam (Station 10) and minimum from the inshore, the Kanyakumari (Cape) West (Station 1). Diversity of gelatinous zooplankton was found to be positively correlated with atmospheric temperature, sea surface temperature and pH. A continuous seasonal study should be conducted to understand the clear impact of physical and chemical factors on the distribution and diversity of gelatinous zooplankton along this region.

APA, Harvard, Vancouver, ISO, and other styles

47

Brooun, Maria, Alexander Klimovich, Mikhail Bashkurov, Bret J. Pearson, Robert E. Steele, and Helen McNeill. "Ancestral roles of atypical cadherins in planar cell polarity." Proceedings of the National Academy of Sciences 117, no. 32 (July 29, 2020): 19310–20. http://dx.doi.org/10.1073/pnas.1917570117.

Full text

Abstract:

Fat, Fat-like, and Dachsous family cadherins are giant proteins that regulate planar cell polarity (PCP) and cell adhesion in bilaterians. Their evolutionary origin can be traced back to prebilaterian species, but their ancestral function(s) are unknown. We identified Fat-like and Dachsous cadherins inHydra, a member of phylum Cnidaria a sister group of bilaterian. We foundHydradoes not possess a true Fat homolog, but has homologs of Fat-like (HyFatl) and Dachsous (HyDs) that localize at the apical membrane of ectodermal epithelial cells and are planar polarized perpendicular to the oral–aboral axis of the animal. Using a knockdown approach we found that HyFatl is involved in local cell alignment and cell–cell adhesion, and that reduction of HyFatl leads to defects in tissue organization in the body column. Overexpression and knockdown experiments indicate that the intracellular domain (ICD) of HyFatl affects actin organization through proline-rich repeats. Thus, planar polarization of Fat-like and Dachsous cadherins has ancient, prebilaterian origins, and Fat-like cadherins have ancient roles in cell adhesion, spindle orientation, and tissue organization.

APA, Harvard, Vancouver, ISO, and other styles

48

Gerhart, D. J. "Emesis, learned aversion, and chemical defense in octocorals: a central role for prostaglandins?" American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 260, no. 5 (May 1, 1991): R839—R843. http://dx.doi.org/10.1152/ajpregu.1991.260.5.r839.

Full text

Abstract:

Prostaglandin A2 and its ester derivatives comprise as much as 8% of the wet tissue weight of some octocoral species such as Plexaura homomalla (phylum Cnidaria, class Anthozoa, subclass Octocorallia). These high levels of prostaglandins, although initially palatable to fish, may function as defensive toxins by inducing emesis and learned aversions in potential predators. As the fish Fundulus heteroclitus and Halichoeres garnoti gain experience through the course of experiments, they increasingly reject foods containing emetic prostaglandins, but do not alter their acceptance of untreated control foods. Emesis is also induced in fish by consumption of tissue or lipid extracts from the subtropical whip coral Leptogorgia virgulata (subclass Octocorallia, order Gorgonacea). The emetic properties of L. virgulata induce learned aversions in the fish Micropterus salmoides and Morone saxatilis. Extracts of L. virgulata do not contain high levels of prostaglandins but do, however, contain other metabolites that appear to mimic the effects of eicosanoids. Some nonprostanoid secondary metabolites may induce emesis by stimulating prostaglandin biosynthesis in the gastric mucosa of predators.

APA, Harvard, Vancouver, ISO, and other styles

49

Daud, Devidson, Joshian N. W. Schaduw, Chatrien Luzianna Sinjal, Janny D. Kusen, Erli Y. Kaligis, and Adnan S. Wantasen. "KONDISI TERUMBU KARANG PADA KAWASAN WISATA PANTAI MALALAYANG KOTA MANADO PROVINSI SULAWESI UTARA DENGAN MENGGUNAKAN METODE UNDERWATER PHOTO TRANSECT." JURNAL PESISIR DAN LAUT TROPIS 9, no. 1 (March 29, 2021): 44. http://dx.doi.org/10.35800/jplt.9.1.2021.33575.

Full text

Abstract:

Coral reefs are coastal ecosystems with the highest level of diversity with around one million species worldwide. Corals are invertebrates belonging to the Phylum Coelenterate (hollow animals) or Cnidaria. The Underwater Photo Transect (UPT) method is a method that utilizes technological developments, both digital camera technology and computer software technology. Capturing data in the field in the form of underwater photos carried out by shooting using a Canon G-16 camera equipped with a waterproof protector (housing). In this study it can be seen that the percentage of hard corals at point 1 is in the medium category, point 2 is in the medium category, and point 3 is in the bad category with the percentage of hard coral cover as follows: point 1 (one) 29.75%, point 2 (two) 31.16%, and point 3 (three) 24.26%, of the three points can represent the overall condition of the coral reefs in Malalayang Beach which is in moderate condition with a percentage of 28.39%.Keywords: Malalayang Beach, Coral Reef, UPT, CPCe

APA, Harvard, Vancouver, ISO, and other styles

50

Bergheim, Bruno Gideon, and Suat Özbek. "Extracellular matrix and morphogenesis in cnidarians: a tightly knit relationship." Essays in Biochemistry 63, no. 3 (August 28, 2019): 407–16. http://dx.doi.org/10.1042/ebc20190021.

Full text

Abstract:

Abstract Cnidarians, members of an early-branching metazoan phylum, possess an extracellular matrix (ECM) between their two epithelial cell layers, called the mesoglea. The cnidarian ECM, which is best studied in Hydra, contains matrix components reflective of both interstitial matrix and basement membrane. The identification of core matrisome components in cnidarian genomes has led to the notion that the basic composition of vertebrate ECM is of highly conserved nature and can be traced back to pre-bilaterians. While in vertebrate classes ECM factors have often diverged and acquired specialized functions in the context of organ development, cnidarians with their simple body plan retained direct links between ECM and morphogenesis. Recent advances in genetic manipulation techniques have provided tools for systematically studying cnidarian ECM function in body axis patterning and regeneration.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Phylum cnidaria'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles