Chrysaora Quinquecirrha Research Articles

Microbial Diversity and Screening for Potential Pathogens and Beneficial Bacteria of Five Jellyfish Species-Associated Microorganisms Based on 16S rRNA Sequencing.

Jellyfish, microorganisms, and the marine environment collectively shape a complex ecosystem. This study aimed to analyze the microbial communities associated with five jellyfish species, exploring their composition, diversity, and relationships. Microbial diversity among the species was assessed using 16S rRNA gene sequencing and QIIME analysis. Significant differences in bacterial composition were found, with distinct dominant taxa in each species: Mycoplasmataceae (99.21%) in Aurelia coerulea, Sphingomonadaceae (22.81%) in Cassiopea andromeda, Alphaproteobacteria_unclassified (family level) (64.09%) in Chrysaora quinquecirrha, Parcubacteria_unclassified (family level) (93.11%) in Phacellophora camtschatica, and Chlamydiaceae (35.05%) and Alphaproteobacteria_unclassified (family level) (38.73%) in Rhopilema esculentum. C. andromeda showed the highest diversity, while A. coerulea exhibited the lowest. Correlations among dominant genera varied, including a positive correlation between Parcubacteria_unclassified (genus level) and Chlamydiaceae_unclassified (genus level). Genes were enriched in metabolic pathways and ABC transporters. The most abundant potential pathogens at the phylum level were Proteobacteria, Tenericutes, Chlamydiae, and Epsilonbacteraeota. The differing microbial compositions are likely influenced by species and their habitats. Interactions between jellyfish and microorganisms, as well as among microorganisms, showed interdependency or antagonism. Most microbial gene functions focused on metabolic pathways, warranting further study on the relationship between pathogenic bacteria and these pathways.

Insights into the discovery and intervention of metalloproteinase in marine hazardous jellyfish

The proliferation of toxic organisms caused by changes in the marine environment, coupled with the rising human activities along the coastal lines, has resulted in an increasing number of stinging incidents, posing a serious threat to public health. Here, we evaluated the systemic toxicity of the venom in jellyfish Chrysaora quinquecirrha at both cellular and animal levels, and found that jellyfish tentacle extract (TE) has strong lethality accompanied by abnormal elevation of blood biochemical indicators and pathological changes. Joint analysis of transcriptome and proteome indicated that metalloproteinases are the predominant toxins in jellyfish. Specially, two key metalloproteinases DN6695_c0_g3 and DN8184_c0_g7 were identified by mass spectrometry of the red blood cell membrane and tetracycline hydrochloride (Tch) inhibition models. Structurally, molecular docking and kinetic analysis are employed and observed that Tch could inhibit the enzyme activity by binding to the hydrophobic pocket of the catalytic center. In this study, we demonstrated that Tch impedes the metalloproteinase activity thereby reducing the lethal effect of jellyfish, which suggests a potential strategy for combating the health threat of marine toxic jellyfish.

Selective Toxicity Effect of Chrysaora quinquecirrha Crude Venom on Human Colorectal Tumor Cells by Directly Targeting Mitochondria.

Objective:Compounds isolated from marine animals have different pharmacological effects. In this study, we investigated the effects of sea nettle (Chrysaora quinquecirrha) crude venom on human colon cancer mitochondria. Methods:First, mitochondria were isolated from healthy colon tissue and cancerous colon tissue, and then mitochondrial function (SDH activity), reactive oxygen species (ROS) level, mitochondrial membrane potential (MMP) collapse, mitochondrial swelling, and cytochrome c release were measured. Results:The results showed that crude venom of Chrysaora quinquecirrha (180, 360 and 720 µg/ml) can significantly impair mitochondrial function (**P<0.01 and ***P<0.001) and consequently increase the level of ROS (*P<0.05 and ****P<0.0001), collapse in MMP (*P<0.05 and ****P<0.0001), mitochondrial swelling (**** P<0.0001) and release of cytochrome c (* P<0.05 and *** P<0.001) only in mitochondria isolated from human colon cancer tissue. Conclusion:The results concluded that crude venom of Chrysaora quinquecirrha (180, 360 and 720 µg/ml) has no side effects on normal mitochondria and only selectively affects cancerous mitochondria. It seems that after further research, Chrysaora quinquecirrha can be considered as a drug candidate for the treatment of patients with colon cancer.

Opechona chloroscombri and Opechona corkumi n. sp. (Digenea: Lepocreadiidae) from the Northern Gulf of Mexico with Phylogenetic Analysis Based on 28S RDNA

This study investigated the identity of 2 lepocreadiid digenean species belonging in the genus Opechona Looss, 1907 that infect littoral fishes of the northern Gulf of Mexico. Opechona chloroscombriNahhas and Cable, 1964, a species previously known only from the Caribbean Sea and the Atlantic Ocean off Brazil, is reported herein from the Atlantic bumper, Chloroscombrus chrysurus (L.), in the northern Gulf of Mexico. A second species infects the gulf butterfish, Peprilus burti Fowler, and the American harvestfish, Peprilus paru (L.), and it is described as a new species that occurs in coastal waters of the north-central and northeastern Gulf of Mexico. Metacercariae infecting the mesoglea of pelagic jellyfishes (Bougainvillia carolinensis [McCady], Chrysaora quinquecirrha [Desor], and Stomolophus meleagris Agassiz) and pelagic comb jellies (Mnemiopsis leidyi Agassiz and Beroe ovata Bruguière) were collected that resemble the new species but require further study to identify. Newly generated sequence fragments (28S rDNA) from both species of Opechona plus 2 other lepocreadiids collected during the study were aligned with publicly available sequences from 18 other lepocreadiids, 6 species of Aephnidiogenidae Yamaguti, 1934, and 2 species of Gorgocephalidae Manter, 1966. The alignment was subjected to Bayesian inference analysis rooted using a gorgocephalid. The resulting tree estimated the positions of both Opechona spp. as being unresolved within a group of taxa that included all available species of Opechona plus available species from the morphologically similar genera ProdistomumLinton, 1910, Preptetos Pritchard, 1960, and Clavogalea Bray, 1985. Although relatively similar in morphology, the 2 studied species of Opechona were surprisingly not closely related. Opechona cablei (Stunkard, 1980) Bray and Gibson, 1990 is herein considered to be a junior synonym of Opechona pyriformis (Linton, 1900) Bray and Gibson, 1990.

High-Quality Genome Assembly of Chrysaora quinquecirrha Provides Insights Into the Adaptive Evolution of Jellyfish.

Jellyfish, such as Chrysaora quinquecirrha, hold an important evolutionary position and have great ecological value. However, limited genomic resources are currently available for studying their basic genetic and development processes. Here, we de novo assembled the first high-quality reference genome of C. quinquecirrha, and successfully annotated 21,606 protein-coding genes. Codon usage analysis identified the frequent use of low-GC-content codons during protein-coding gene translation. Analysis of the relative evolution rate indicated that jellyfish had a faster evolution rate than sea anemones but slower rate than the species in Hydra. Phylogenetic analysis with two other species of jellyfish indicated that Aurelia aurita and Nemopilema nomurai have a closer relationship with each other than with C. quinquecirrha, with divergence from their common ancestor occurring ≈475.7 million years ago. Our study not only showed the genomic characteristics and molecular adaptive evolution of C. quinquecirrha, but also provides valuable genomic resources for further study on complex developmental processes and environmental adaptations.

Complete mitochondrial genome of the jellyfish, Chrysaora pacifica (Goette, 1886) (Cnidaria, Scyphozoa) and the phylogenetic relationship in the related species

The complete mitochondrial genome sequences of giant jellyfish Chrysaora pacifica, a scyphozoan species inhabiting the Bohai Sea water in China, is firstly described and analyzed in this research. The mitogenome is a circular molecule 16,964 bp in length, including 13 protein-coding genes (Cox 1, Cox2, Atp 8, Atp 6, Cox 3, ND2, ND5, ND 6, ND3, ND4L,ND1,ND4, Cob), 2 tRNAs (trnW, trnM), 2 rRNA genes (small subunit RNA and large subunit RNA). The neighbor-joining (NJ) phylogenetic tree in the related species showed that C. pacifica is close to Chrysaora quinquecirrha.

Risk screening of the potential invasiveness of non-native jellyfishes in the Mediterranean Sea

The aim of the present study was to risk screen 45 jellyfish species (30 hydromedusae, 14 scyphomedusae, one cubomedusa) for their potential invasiveness in the Mediterranean Sea to aid managers in making informed decisions on targeting appropriate species for management. Using the Aquatic Species Invasiveness Screening Kit (AS-ISK), calibrated basic and climate-change threshold assessment scores of 6.5 and 12.5, respectively, were identified for distinguishing reliably between species that pose ‘low-to-medium’ and ‘high’ risk of becoming invasive in the risk assessment area. Using these thresholds, 16 species were classified as high risk, 23 as medium risk and six as low risk under current climate conditions. Whereas, under future climate conditions, 13, 30 and two species, respectively, were classified as high, medium and low risk, respectively. Upside-down jellyfish Cassiopea andromeda, Australian spotted jellyfish Phyllorhiza punctata, sea nettle Chrysaora quinquecirrha and Rhopilema nomadica were the highest-scoring species, with the maximum increase in risk score under predicted climate change conditions being achieved by C. andromeda.

Temperature-driven asexual reproduction and strobilation in three scyphozoan jellyfish polyps

Increased atmospheric carbon dioxide (CO2) and subsequent climate warming is a critical threat to our oceans. Increased ocean temperatures are speculated to be a driving factor in controlling jellyfish populations worldwide; warmer temperatures increase asexual budding of benthic polyps, and many species strobilate in the spring as water temperatures begin to warm following cold winters. As ocean temperatures rise, it is important to determine thermal triggers in reproduction in jellyfish populations. This study investigated the effects of temperature on 1) asexual (budding) reproductive rates, 2) timing of strobilation, and 3) strobilation success (number of polyps strobilating and number of ephyrae per polyp), for Aurelia aurita, Chrysaora quinquecirrha, and Chrysaora fuscescens polyps exposed to constant temperatures of 5 °C, 10 °C, 15 °C, and 20 °C. Asexual reproduction rates were similar for all species and increased with increasing temperature. Strobilation occurred at 10 °C for all species and all three species began strobilation at the same time (21–23 days). Aurelia aurita and C. fuscescens also strobilated at 15 °C, but strobilated later, had less polyps strobilating, and produced less ephyrae per polyp than the same species at 10 °C. If temperature contributes to instigation of strobilation, ocean temperatures and the timing of warming will be a primary control of the size and distribution of adult populations. Slight warming may benefit temperate species such as A. aurita that can strobilate successfully at increased temperatures, but other species may be restricted by warming waters. Further, if warming is such that proper overwintering temperatures do not occur, polyps may not be exposed to conditions enabling strobilation. While it has been speculated that jellyfish will be favored under warmer ocean conditions, future climate change may prohibit species that require specific conditions to strobilate.

Medusozoa in Portugal: impact on the ecosystems and development of DNA-based tools for the early forecasting of mass occurrences

Medusozoa in Portugal: impact on the ecosystems and development of DNA-based tools for the early forecasting of mass occurrences

Multigene phylogeny of the scyphozoan jellyfish family Pelagiidae reveals that the common U.S. Atlantic sea nettle comprises two distinct species (Chrysaora quinquecirrha and C. chesapeakei).

BackgroundSpecies of the scyphozoan family Pelagiidae (e.g., Pelagia noctiluca, Chrysaora quinquecirrha) are well-known for impacting fisheries, aquaculture, and tourism, especially for the painful sting they can inflict on swimmers. However, historical taxonomic uncertainty at the genus (e.g., new genus Mawia) and species levels hinders progress in studying their biology and evolutionary adaptations that make them nuisance species, as well as ability to understand and/or mitigate their ecological and economic impacts.MethodsWe collected nuclear (28S rDNA) and mitochondrial (cytochrome c oxidase I and 16S rDNA) sequence data from individuals of all four pelagiid genera, including 11 of 13 currently recognized species of Chrysaora. To examine species boundaries in the U.S. Atlantic sea nettle Chrysaora quinquecirrha, specimens were included from its entire range along the U.S. Atlantic and Gulf of Mexico coasts, with representatives also examined morphologically (macromorphology and cnidome).ResultsPhylogenetic analyses show that the genus Chrysaora is paraphyletic with respect to other pelagiid genera. In combined analyses, Mawia, sampled from the coast of Senegal, is most closely related to Sanderia malayensis, and Pelagia forms a close relationship to a clade of Pacific Chrysaora species (Chrysaora achlyos, Chrysaora colorata, Chrysaora fuscescens, and Chrysaora melanaster). Chrysaora quinquecirrha is polyphyletic, with one clade from the U.S. coastal Atlantic and another in U.S. Atlantic estuaries and Gulf of Mexico. These genetic differences are reflected in morphology, e.g., tentacle and lappet number, oral arm length, and nematocyst dimensions. Caribbean sea nettles (Jamaica and Panama) are genetically similar to the U.S. Atlantic estuaries and Gulf of Mexico clade of Chrysaora quinquecirrha.DiscussionOur phylogenetic hypothesis for Pelagiidae contradicts current generic definitions, revealing major disagreements between DNA-based and morphology-based phylogenies. A paraphyletic Chrysaora raises systematic questions at the genus level for Pelagiidae; accepting the validity of the recently erected genus Mawia, as well as past genera, will require the creation of additional pelagiid genera. Historical review of the species-delineating genetic and morphological differences indicates that Chrysaora quinquecirrha Desor 1848 applies to the U.S. Coastal Atlantic Chrysaora species (U.S. Atlantic sea nettle), while the name C. chesapeakei Papenfuss 1936 applies to the U.S. Atlantic estuarine and Gulf of Mexico Chrysaora species (Atlantic bay nettle). We provide a detailed redescription, with designation of a neotype for Chrysaora chesapeakei, and clarify the description of Chrysaora quinquecirrha. Since Caribbean Chrysaora are genetically similar to Chrysaora chesapeakei, we provisionally term them Chrysaora c.f. chesapeakei. The presence of Mawia benovici off the coast of Western Africa provides a potential source region for jellyfish introduced into the Adriatic Sea in 2013.

Top-Down Impacts of Sea Nettles (Chrysaora quinquecirrha) on Pelagic Community Structure in Barnegat Bay, New Jersey, U.S.A.

ABSTRACT Bologna, P.A.X.; Gaynor, J.J.; Barry C.L., and Restaino, D.J., 2017. Top-down impacts of sea nettles (Chrysaora quinquecirrha) on pelagic community structure in Barnegat Bay, New Jersey, U.S.A.. In: Buchanan, G.A.; Belton, T.J., and Paudel, B. (eds.), A Comprehensive Assessment of Barnegat Bay–Little Egg Harbor, New Jersey. Coastal communities are substantially affected by human activities and create environments conducive to opportunistic species and structural changes in food webs. The Mid-Atlantic coast of the United States is highly urbanized with significant landscape modification and elevated pollutant loads. The appearance and development of resident populations of the Atlantic sea nettle (Chrysaora quinquecirrha) in Barnegat Bay, New Jersey demonstrates a successful establishment to this estuary. This research indicates that two species of gelatinous zooplankton (Mnemiopsis leidyi, C. quinquecirrha) play important structuring roles in the pelagic community. Specifically, M. leidyi exerts ...

QPCR Detection of Early Life History StageChrysaora quinquecirrha(Sea Nettles) in Barnegat Bay, New Jersey

ABSTRACT Gaynor, J.J.; Bologna, P.A.X.; Restaino, D.J., and Barry, C.L., 2017. qPCR detection of early life history stage Chrysaora quinquecirrha (sea nettles) in Barnegat Bay, New Jersey. In: Buchanan, G.A.; Belton, T.J., and Paudel, B. (eds.), A Comprehensive Assessment of Barnegat Bay–Little Egg Harbor, New Jersey. The sea nettle Chrysaora quinquecirrha has become abundant in the Barnegat Bay estuary and frequently blooms in warm summer months. Various factors have been attributed to the increasing localized appearance of sea nettles and other jellyfish including eutrophication, overfishing, global warming, construction, and species introduction. Despite its abundance and frequent distribution within estuarine systems, very little work has been done to detect and quantify the early life history stages of this organism. Free-swimming larval stages of C. quinquecirrha can be detected and quantified using a quantitative polymerase chain reaction assay specific for the C. quinquecirrha 16S ribosomal (r)DNA...

Abundance and patchiness of Chrysaora quinquecirrha medusae from a high-frequency time series in the Choptank River, Chesapeake Bay, USA

Despite strong control over marine plankton dynamics and negative impacts on human activities, jellyfish are not well quantified due primarily to sampling difficulties with nets. Therefore, some of the longest records of jellyfish are visual shore-based surveys. As surface counting is inexpensive and simple, it is of interest to determine what can be learned from such records as well as the usefulness of the method. We analyzed a 4-year high-frequency time series of Chrysaora quinquecirrha medusa counts collected using three sampling methods in the Choptank River, Chesapeake Bay. Medusa abundance was modeled by change points and was highly correlated between the sampling methods. The remaining signal was random, and indices of aggregation [fit to the Poisson distribution, Taylor’s Power Law (TPL), and Morisita’s Index] indicated that medusae were aggregated. TPL suggested that patches grew in the number of individuals as abundance increased. Additionally, a simple conceptualization of where the time series sampled in space revealed that the upper bound of patch size was on the order of kilometers. Our results enhance the knowledge of local C. quinquecirrha abundance and patchiness, alluding to processes that generate these patterns. This study also provides direction for improving population monitoring from visual shore-based surveys.

Diet assessment of the Atlantic Sea Nettle Chrysaora quinquecirrha in Barnegat Bay, New Jersey, using next-generation sequencing.

Next-generation sequencing (NGS) methodologies have proven useful in deciphering the food items of generalist predators, but have yet to be applied to gelatinous animal gut and tentacle content. NGS can potentially supplement traditional methods of visual identification. Chrysaora quinquecirrha (Atlantic sea nettle) has progressively become more abundant in Mid-Atlantic United States' estuaries including Barnegat Bay (New Jersey), potentially having detrimental effects on both marine organisms and human enterprises. Full characterization of this predator's diet is essential for a comprehensive understanding of its impact on the food web and its management. Here, we tested the efficacy of NGS for prey item determination in the Atlantic sea nettle. We implemented a NGS 'shotgun' approach to randomly sequence DNA fragments isolated from gut lavages and gastric pouch/tentacle picks of eight and 84 sea nettles, respectively. These results were verified by visual identification and co-occurring plankton tows. Over 550000 contigs were assembled from ~110million paired-end reads. Of these, 100 contigs were confidently assigned to 23 different taxa, including soft-bodied organisms previously undocumented as prey species, including copepods, fish, ctenophores, anemones, amphipods, barnacles, shrimp, polychaete worms, flukes, flatworms, echinoderms, gastropods, bivalves and hemichordates. Our results not only indicate that a 'shotgun' NGS approach can supplement visual identification methods, but targeted enrichment of a specific amplicon/gene is not a prerequisite for identifying Atlantic sea nettle prey items.

Growth, development and transition rate of Chrysaora quinquecirrha ephyrae to juvenile state under different diets

Event Abstract Back to Event Growth, development and transition rate of Chrysaora quinquecirrha ephyrae to juvenile state under different diets Hugo Batista1, Margarida Ferreira1, Jose M. Louçanas2*, Nuria Baylina1 and Teresa Baptista2 1 Oceanário de Lisboa, Oceanário de Lisboa, Portugal 2 School of Tourism and Maritime Technology (ESTM), Aquaculture, Portugal The knowledge associated to jellyfish production is an area that has much to discover. Different techniques have been refined over the years. For the species covered in this work, Chrysaora quinquecirrha, one of the biggest challenges is the transition from ephyrae to juvenile state. In order to determine the diet that promotes a higher success of transition from ephyrae to juveniles, and a higher growth rate while optimizing the rational use of resources two trials were conducted. Each trial included four experiments in mini-kreisels varying only the elements supplied in addition to the base diet of rotifers and artemia nauplii. Diets of the first test: 1) Aurelia aurita mash; 2) Aurelia aurita mash in conjunction with Clupea harengus mash; 3) potassium iodide solution (10-3 M) and 4) potassium iodide solution (10-3 M) in conjunction with Clupea harengus mash. Diets used in the second test: 1) rotifers and artemia nauplii without extra elements; 2) Clupea harengus mash 3) potassium iodide (10-5 M) and 4) potassium iodide (10-5 M) in conjunction with Clupea harengus mash. In order to estimate the growth rates of the ephyrae, their diameters (distance between opposing rhopalia) were measured once per week. According to the results of the first test, it was found that the diet with Aurelia aurita mash allowed an ephyrae transition rate to juveniles of 100% over a period of 7 weeks with an average diameter of 11.200 mm at the end of the transition. The Clupea harengus mash in conjunction with the Aurelia aurita mash allowed a transition rate to juveniles of 90% within 6 weeks with an average diameter at the end of the transition of 11.850 mm. The experiments with the two diets containing potassium iodide (10-3 M) were not completed due to the detection of oxidants in the water on these kreisels. Regarding the second test, it was found that the diet with only rotifers and artemia nauplii showed a transition rate of 30% over 10 weeks with an average diameter of 6.448 mm. The diet with the addition of potassium iodide supplement (10-5 M) had the same transition rate for the same period as the previously referred diet, only varying on the average diameter achieved that was 6.907 mm. The diet with Clupea harengus mash registered a 100% rate transition on a 7 week period with an average diameter of 9.868 mm. The test with Clupea harengus mash with potassium iodide supplement (10-5 M) registered a transition rate to juvenile of 100% within a period of 8 weeks with an average diameter of 8.840 mm. Keywords: Chrysaora quinquecirrha, Ephyrae, juvenile, Clupea harengus, Potassium iodide (KI), Aurelia aurita. Conference: IMMR | International Meeting on Marine Research 2016, Peniche, Portugal, 14 Jul - 15 Jul, 2016. Presentation Type: Poster presentation Topic: Aquaculture Citation: Batista H, Ferreira M, Louçanas JM, Baylina N and Baptista T (2016). Growth, development and transition rate of Chrysaora quinquecirrha ephyrae to juvenile state under different diets. Front. Mar. Sci. Conference Abstract: IMMR | International Meeting on Marine Research 2016. doi: 10.3389/conf.FMARS.2016.04.00044 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 13 May 2016; Published Online: 13 Jul 2016. * Correspondence: Mr. Jose M Louçanas, School of Tourism and Maritime Technology (ESTM), Aquaculture, Peniche, Peniche, Portugal, josegria@hotmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract Supplemental Data The Authors in Frontiers Hugo Batista Margarida Ferreira Jose M Louçanas Nuria Baylina Teresa Baptista Google Hugo Batista Margarida Ferreira Jose M Louçanas Nuria Baylina Teresa Baptista Google Scholar Hugo Batista Margarida Ferreira Jose M Louçanas Nuria Baylina Teresa Baptista PubMed Hugo Batista Margarida Ferreira Jose M Louçanas Nuria Baylina Teresa Baptista Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Comparative study of the toxic effects of Chrysaora quinquecirrha (Cnidaria: Scyphozoa) and Chironex fleckeri (Cnidaria: Cubozoa) venoms using cell-based assays

The venoms of jellyfish cause toxic effects in diverse biological systems that can trigger local and systemic reactions. In this study, the cytotoxic and cytolytic effects of Chrysaora quinquecirrha and Chironex fleckeri venoms were assessed and compared using three in vitro assays. Venoms from both species were cytotoxic to fish gill cells and rat cardiomyocytes, and cytolytic in sheep erythrocytes. Both venoms decreased cell viability in a concentration-dependent manner; however, the greatest difference in venom potencies was observed in the fish gill cell line, wherein C. fleckeri was 12.2- (P = 0.0005) and 35.7-fold (P < 0.0001) more potently cytotoxic than C. quinquecirrha venom with 30 min and 120 min cell exposure periods, respectively. Gill cells and rat cardiomyocytes exposed to venoms showed morphological changes characterised by cell shrinkage, clumping and detachment. The cytotoxic effects of venoms may be caused by a group of toxic proteins that have been previously identified in C. fleckeri and other cubozoan jellyfish species. In this study, proteins homologous to CfTX-1 and CfTX-2 toxins from C. fleckeri and CqTX-A toxin from Chironex yamaguchii were identified in C. quinquecirrha venom using tandem mass spectrometry. The presence and relative abundance of these proteins may explain the differences in venom potency between cubozoan and scyphozoan jellyfish and may reflect their importance in the action of venoms.

Comparative muscle development of scyphozoan jellyfish with simple and complex life cycles.

BackgroundSimple life cycles arise from complex life cycles when one or more developmental stages are lost. This raises a fundamental question - how can an intermediate stage, such as a larva, be removed, and development still produce a normal adult? To address this question, we examined the development in several species of pelagiid jellyfish. Most members of Pelagiidae have a complex life cycle with a sessile polyp that gives rise to ephyrae (juvenile medusae); but one species within Pelagiidae, Pelagia noctiluca, spends its whole life in the water column, developing from a larva directly into an ephyra. In many complex life cycles, adult features develop from cell populations that remain quiescent in larvae, and this is known as life cycle compartmentalization and may facilitate the evolution of direct life cycles. A second type of metamorphic processes, known as remodeling, occurs when adult features are formed through modification of already differentiated larval structures. We examined muscle morphology to determine which of these alternatives may be present in Pelagiidae.ResultsWe first examined the structure and development of polyp and ephyra musculature in Chrysaora quinquecirrha, a close relative of P. noctiluca with a complex life cycle. Using phallotoxin staining and confocal microscopy, we verified that polyps have four to six cord muscles that persist in strobilae and discovered that cord muscles is physically separated from ephyra muscle. When cord muscle is removed from ephyra segments, normal ephyra muscle still develops. This suggests that polyp cord muscle is not necessary for ephyra muscle formation. We also found no evidence of polyp-like muscle in P. noctiluca. In both species, we discovered that ephyra muscle arises de novo in a similar manner, regardless of the life cycle.ConclusionsThe separate origins of polyp and ephyra muscle in C. quinquecirrha and the absence of polyp-like muscle in P. noctiluca suggest that polyp muscle is not remodeled to form ephyra muscle in Pelagiidae. Life cycle stages in Scyphozoa may instead be compartmentalized. Because polyp muscle is not directly remodeled, this may have facilitated the loss of the polyp stage in the evolution of P. noctiluca.Electronic supplementary materialThe online version of this article (doi:10.1186/s13227-015-0005-7) contains supplementary material, which is available to authorized users.

Local Wind Dynamics Influence the Distribution and Abundance of Chrysaora quinquecirrha in North Carolina, USA

Sea nettles, Chrysaora quinquecirrha, have been observed annually in the Neuse River Estuary (NRE), an area of substantial recreation in North Carolina. The purpose of this study was to evaluate what environmental factors may affect jellyfish abundance at NRE recreational sites. Jellyfish were counted and abiotic variables were measured bi-weekly at six recreation sites from May to August, 2011 and 2012. The relationship between wind (magnitude and direction) and jellyfish abundance was also investigated, as circulation within the NRE is primarily a function of wind. The 2 years differed in stream flow, salinity, and temperature, with drought conditions prevalent in 2011. Wind speed and direction did not differ between the 2 years; however, the number of high-speed wind events (±1.4 standard deviation of daily mean speed) did differ across years. A total of 3241 jellyfish were observed, with peak counts in July and minimum counts in August. There were significant differences in mean sea nettle counts between sites, specifically between north and south shorelines. Northeast-east and southeast-southwest wind events were correlated to sea nettle abundance (m−3) when a lag period was included. We concluded that NRE wind dynamics are one of the factors influencing jellyfish-human interactions at the six recreational sites in the NRE. The relatively strong influence of wind, compared to the abiotic variables temperature and salinity, suggests that prediction of sea nettle abundances at these sites subsequent to wind events is possible.

Model-to-data comparisons reveal influence of jellyfish interactions on plankton community dynamics

Taxonomic shifts can alter predator feeding preference and modify ecosystem dynamics through top-down control. In Barnegat Bay-Little Egg Harbor Estuary (New Jersey, USA), sea nettle Chrysaora quinquecirrha abundances have increased in the northern portions of the estuary. We evaluated the geographical variation in top-down influence of C. quinquecirrha on plankton community dynamics. We simulated a range of jellyfish- to copepod-dominated eco- systems using a size-resolved nutrientphytoplanktonzooplankton (NPZ) model. Zooplankton feeding was parameterized as a community average based on predatorprey size ratios and breadth of prey sizes of dominant species. We compared model outputs to data collected in the estuary during 2 summer months of high C. quinquecirrha abundance. We predicted that data from the northern region would be more similar to the jellyfish-dominated model outputs, because C. quinquecirrha abundance is higher in the north. Contrary to expectations, all northern sites had observational data more similar to the copepod-dominated model outputs, and the site that was most similar to the jellyfish-dominated model outputs was in the C. quinquecirrha-free southern region. These results may indicate complex interactions between C. quinquecirrha and the ctenophore Mnemiopsis leidyi, a voracious copepod predator that is nearly absent in the northern region despite having wide environmental tolerances. Predation by C. quinquecirrha may limit the distribution of M. leidyi and indirectly strengthen copepod dominance in the northern region of the estuary. These results suggest that top-down control by jellyfish can be strongly influenced by competition among gelatinous taxa.

Predator-mediated landscape structure: seasonal patterns of spatial expansion and prey control by Chrysaora quinquecirrha and Mnemiopsis leidyi

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 510:183-200 (2014) - DOI: https://doi.org/10.3354/meps10850 Predator-mediated landscape structure: seasonal patterns of spatial expansion and prey control by Chrysaora quinquecirrha and Mnemiopsis leidyi Denise Breitburg*, Rebecca Burrell Smithsonian Environmental Research Center, PO Box 28, Edgewater, Maryland 21037, USA *Corresponding author: breitburgd@si.edu ABSTRACT: The scyphomedusa Chrysaora quinquecirrha and lobate ctenophore Mnemiopsis leidyi are dominant consumers in the planktivorous food web in Chesapeake Bay, USA, and are important predators throughout much of their ranges. Our studies in the Patuxent River (a subestuary of Chesapeake Bay) and its tributary creeks suggest successive waves of population spread and trophic influence of these 2 gelatinous species in opposing directions across the aquatic landscape. In years when both species were abundant, Mnemiopsis appeared first in the main channel of the Patuxent River and initially was most abundant in the bottom layer of the water column. Mnemiopsis densities then rapidly increased in shallow tributaries and coves, with distributions likely caused by a combination of transport and temporally and spatially varying patterns of growth and reproduction. In contrast, densities of Chrysaora ephyrae were initially highest in small coves and tributary creeks, with densities of Chrysaora medusae spreading outward from these small systems to the main river as summer progressed. We found no conclusive evidence for tidally-cued vertical migrations of either species or directional swimming by Chrysaora that would create these differing spatio-temporal patterns. As Chrysaora increased and spread, it likely reduced or eliminated Mnemiopsis by direct predation, and possibly through the effect that partial predation could have on Mnemiopsis reproduction. Because of differences in diets and feeding rates, these shifting temporal and spatial patterns of medusa and ctenophore dominance potentially influence spatial distributions and temporal patterns of survival of ichthyoplankton, oyster larvae, and copepods. KEY WORDS: Gelatinous zooplankton · Estuary · Food web · Spatial distributions · Chesapeake Bay Full text in pdf format Supplementary material PreviousNextCite this article as: Breitburg D, Burrell R (2014) Predator-mediated landscape structure: seasonal patterns of spatial expansion and prey control by Chrysaora quinquecirrha and Mnemiopsis leidyi . Mar Ecol Prog Ser 510:183-200. https://doi.org/10.3354/meps10850 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 510. Online publication date: September 09, 2014 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2014 Inter-Research.