Species Of Box Jellyfish Research Articles

Copula lucentia sp. nov., a new box jellyfish (Cnidaria: Cubozoa: Carybdeida) from Western Mediterranean Sea

A new species of box jellyfish, Copula lucentia sp. nov., is described from El Campello, Spain, and compared to the holotype of Copula sivickisi that was successfully recovered after being lost for almost 60 years. So far, the only cubozoan species recorded in the Western Mediterranean was Carybdea marsupialis. The genus Copula just included the type species (Copula sivickisi) reported from different localities in the Pacific, Atlantic, and Indian Oceans. Morphologically, this new species possesses the typical characteristics of the genus Copula (four adhesive pads on the apex and a vertical keyhole-shaped rhopalial niche ostium) but it can be differentiated from the C. sivickisi holotype by the velarial canal pattern. In C. lucentia sp. nov., the velarial canal roots taper towards the velarial rim and each root bears one to two narrow triangular canals with sharp tips, resembling a bird beak. In contrast, the velarial canal roots of C. sivickisi bear two short, broad canals that increase breadth towards the velarial rim and split up into three- to six-lobed, finger-like canals with rounded tips, giving the canal pattern a paw-like appearance. Molecular analyses of mitochondrial cytochrome c oxidase subunit I (COI) and nuclear 16S ribosomal DNA genes confirm the distinction of the new species and show that there are even more Copula species than expected, but which will not be focused on here. This study highlights not only that there are species yet to be discovered in the Mediterranean Sea but that a revision of the genus Copula is necessary.

Cubomedusae (Cubozoa, Carybdeida, Carukiidae) in Hong Kong, China: first records of cubozoans in Chinese waters confirmed using citizen science and digital authentication

The Hong Kong Jellyfish Project uses photographs and videos from citizen scientists to document the occurrence of jellyfish in this region. Based on these records, we describe sightings of two previously unrecorded species of box jellyfish, Malo filipina (Bentlage & Lewis, 2012) and an unidentified species of Morbakka sp. Gershwin, 2008, in Hong Kong Special Administrative Region, China. This understanding of where these species currently occur is important due to the potential impacts of box jellyfish on human activities and their role in local ecosystems.

Real-time PCR assay for detection of Environmental DNA from <i>Chironex yamaguchii</i>

The box jellyfish Chironex yamaguchii is a highly venomous cubomedusa, also known as “habu-kurage” in Japan. It is a significant threat to marine activities in Okinawa in southern Japan. Annually, envenomation of the species causes nearly 100 to 200 injuries in the Okinawa Prefecture. The present study developed a species-specific real-time PCR assay to analyze environmental DNA (eDNA) for rapid detection of jellyfish in water samples. Primers and probe were designed based on the sequences of the mitochondrial cytochrome c oxidase subunit I region using tissue samples of nine specimens obtained from the Okinawa Prefecture. The specificity of the real-time PCR assay was confirmed by amplifying the DNA samples of 10 different box jellyfish species. A practical assay for eDNA detection was successful on water samples obtained from the natural habitat of C. yamaguchii. In addition, the degradation rate of eDNA in the tank experiment was 65% of the initial concentration at 1 h, 22% at 12 h, and 3% at 48 h.

Alatina alata box jellyfish monthly migrations in Hawai’i: Lunar and physical oceanographic triggers

Alatina alata, a species of box jellyfish, is found in distinct localities throughout tropical zones in the Atlantic, Pacific, and Indian Oceans, and is responsible for the most severe stings reported in Hawaiian coastal waters. Alatina alata is unique among species of box jellyfish (Cubozoa) in that it is only observed in shallow shoreline waters during lunar period-specific monthly mass aggregations and beaching events, which occur 8–10 days after each full moon. At other times of the lunar cycle, this species has been documented in pelagic zone surveys and is not observed close to shore (0 to 5 meter deep area, 0–100 m from shoreline). To assess potential ecological and environmental triggers for the synchronized shoreward migration behavior of Alatina alata, we investigated 14 years of beach count data in relation to lunar transit, luminosity, tides, and ocean currents using: a 14-year time series of Alatina alata pre-dawn counts; morphometric and reproductive status analyses; three full-transect nighttime shipboard observations; modeling studies; and additional supporting data. Model simulations show a persistent anticyclonic eddy in the study area, which may act as a source point for the jellyfish. Additionally, in situ night-long observations over three separate months revealed for the first time that Alatina alata actively swam en masse from over one mile offshore towards the shore before moonrise. Over 500 animals were observed and all showed strong shoreward swimming behavior perpendicular to the prevailing current. While the monthly populations each demonstrated heterogeneity with regard to size and beaching time, there was a slight trend towards the beaching of larger jellyfish first. Despite this heterogeneity in size, all animals were sexually mature adults replete with gametes or freshly spent. For the first time, we document that a key number of hours of darkness between twilight and moon rise correlate with the migration, and we hypothesize that this lunar cycle specific event triggers gonadal maturation in adult jellies, and maturation then triggers migrations to the shallow reef zone for spermcast mating.

Initial Findings Suggest Box Jellyfish Encounters along Shallow Philippine Coastlines are Predictable

Jellyfish stings account for numerous deaths in the Philippines. Despite this, there is little scientific information on the identity, distribution, seasonality, and ecology of the box jellyfish species involved. We present initial findings of three months (April–June 2021) of monitoring the abundance of and envenomations by box jellyfishes in eastern and western Luzon. Emergent patterns suggest encounters between box jellyfish and people are more likely to occur in beach areas within a few kilometers from rivers when tidal ranges are large, particularly around the flood phase of high tide. Encounters are also more likely on coasts where the monsoon winds blow onshore during the warmer months, bringing these animals closer to beach areas. They then stay longer in the shallows when the seas are calm. Beachgoers are, thus, advised to plan their destinations and activities carefully and wear protective clothing when venturing into shallow coastal areas.

Estimation of local incidence of jellyfish envenomation in developed marine coastal areas and large populated island on the western coast of Peninsular Malaysia using case surveillance of government health facilities in Manjung, Perak and Langkawi Island.

Jellyfish stings are one of the commonest causes of marine animal related injuries in human. Despite mostly being harmless, box jellyfish species can cause major stings with fatalities or systemic envenoming symptoms. There are 15-20 species identified to be life-threatening. There are few reported cases that suggest the presence of deadly box jellyfish in the Malaysian coast. However, numbers of stings around Malaysia are still under reported. This observational study was conducted in Manjung, Perak and Langkawi Island to look at the pattern and incidence of jellyfish stings which occur within 1 year. There were 45 sting incidents reported with the highest number of cases occurred in December and February. Cases mainly involved young adults aged 10 to 29 years old. The most common clinical symptom that presented was sudden and persistent pain. Vinegar was applied as first aid in 53.3% of reported stings. All patients were treated symptomatically and discharged well. Stings occurred at mean sea surface temperature of 29.38°C and the wind speed of 7.6 knots. All cases were mild and did not require antivenom. The study showed that the occurrence of jellyfish stings are affected by weather conditions. Jellyfish stings occur seasonally, thus making it predictable and easily preventable with public awareness, early first aid application and use of jellyfish nets.

Rapid and Accurate Species-Specific PCR for the Identification of Lethal Chironex Box Jellyfish in Thailand.

Box jellyfish are extremely potent venom-producing marine organisms. While they have been found worldwide, the highest health burden has been anticipated to be the tropical Indo-Pacific of Southeast Asia (SEA). At least 12 Cubozoan species have now been documented in Thai waters, and many of them inflict acutely lethal strings, especially those under the order Chirodropida. Our previous study has successfully differentiated species of box jellyfish using DNA sequencing to support the morphological study. In this study, we specifically designed polymerase chain reaction (PCR) primers for the 16S ribosomal RNA (rRNA) gene and the mitochondrial DNA cytochrome oxidase subunit I (COI) gene of lethal Thai Chironex species. The SYBR green-based real-time PCR panel was performed for rapid species identification. The sensitivity and specificity of the panel were determined by testing samples of different species. Moreover, we applied the panel to the tentacle sample from a real patient, which helped confirm the animal-of-cause of envenomation. Our results show a success for species identification of box jellyfish using 16S rRNA and COI PCR panel, which revealed congruence between molecular and morphological identification. Furthermore, the panel worked very well with the unknown samples and jellyfish tissue from the real envenomation case. The results demonstrated that molecular panels were able to identify three species of Chironex box jellyfish both rapidly and accurately, and can be performed without having a complete specimen or morphological study.

Irukandji-like syndrome caused by single-tentacle box jellyfish found in Thailand, 2007-2019.

Irukandji syndrome definition is still widely misunderstood. Irukandji-like syndrome is more unclear than Irukandji syndrome. This study aimed to describe Irukandji-like syndrome in cases involving stinging by single-tentacle box jellyfish species in Thailand. Surveillance system and networks of toxic jellyfish incidents were established to enable case detection. In the period 2007 to 2019, all cases of stinging by single-tentacle box jellyfish resulting in collapse, hospital attendance or death were investigated. The majority of the 19 Irukandji-like syndrome cases were male (68.2%), median age 35.0 years (range 6.0-60.0), and Thai nationality (52.3%). Clinical manifestations of Irukandji-like syndrome were categorised as severe wound pain with immediate systemic reaction (66.7%), moderate wound pain with gradual systemic reaction (16.7%), and moderate wound pain with the immediate systemic reaction after a physical/chemical trigger (16.7%). The pain occurring when being stung differed from the pain occurring during the systemic reaction. The five most common symptoms were pain (100.0%), high blood pressure (100.0%), palpitations (86.7%), respiratory distress (52.6%), and near collapse/collapse (31.6%). The pain occurs when being stung was excruciating or burning pain at the wounds, felt like an electric shock, and rapidly expanded to heart pain. While the pain occurring during the systemic reaction was back pain, muscle pain, joint pain, abdominal pain, and body aches. The marks from the tentacles appeared similar in appearance to the caterpillar tracks of tanks. In 6 cases the species could be identified and all of them involving the Morbakka spp. This was the largest study of Irukandji-like syndrome cases involving stings by single-tentacle box jellyfish in Thailand and the different clinical manifestations might be caused by different species of single-tentacle box jellyfish.

Isolation, Structure Determination, and Synthesis of Cyclic Tetraglutamic Acids from Box Jellyfish Species Alatina alata and Chironex yamaguchii.

Cubozoan nematocyst venoms contain known cytolytic and hemolytic proteins, but small molecule components have not been previously reported from cubozoan venom. We screened nematocyst extracts of Alatina alata and Chironex yamaguchii by LC-MS for the presence of small molecule metabolites. Three isomeric compounds, cnidarins 4A (1), 4B (2), and 4C (3), were isolated from venom extracts and characterized by NMR and MS, which revealed their planar structure as cyclic γ-linked tetraglutamic acids. The full configurational assignments were established by syntheses of all six possible stereoisomers, comparison of spectral data and optical rotations, and stereochemical analysis of derivatized degradation products. Compounds 1–3 were subsequently detected by LC-MS in tissues of eight other cnidarian species. The most abundant of these compounds, cnidarin 4A (1), showed no mammalian cell toxicity or hemolytic activity, which may suggest a role for these cyclic tetraglutamates in nematocyst discharge.

Histomorphological comparison of testes in species of box jellyfish (Cnidaria; Cubozoa): does morphology differ with mode of reproduction and fertilization?

Cubozoa jellyfish species exhibit either internal or external fertilization, and reproductive behavior involving spermcasting or complex copulatory sexual behavior, but male gonad morphology has not been investigated broadly in cubozoans. In this study, a histological comparison was conducted of the testes of four cubozoan species in two orders: Carybdea marsupialis (Carybdeidae), Morbakka virulenta (Carukiidae), and Tamoya cf. haplonema (Tamoyidae) in Carybdeida and Chiropsalmus quadrumanus (Chiropsalmidae) in Chirodropida. Our results show spermatic follicles present in all species, with spermatogenesis occurring in two layers, the gastrodermis and the gonadal mesoglea. Specimens were either immature males or unspawned males, except in the case of Tamoya cf. haplonema which displayed rupture sites in the wall of the follicles, indicating prior release of sperm. Interspecific comparative histological study revealed that spermatogenesis generally occurs in a polarized manner towards the lumen of the spermatic follicle, with mature spermatozoa in the center awaiting gonadal rupture and release for either internal or external fertilization. Furthermore, we provide a synopsis of the histological findings to date on cubozoan testes, emphasizing incidences of conserved male gonad morphology regardless of mode of fertilization, in addition to separate novelties that have arisen in two internally fertilizing lineages, each exhibiting unique reproductive behavior. Further taxon-sampling of additional species at different development stages may reveal a broader diversity in testes morphology across Cubozoa and serve as a basis for a deeper investigation into the emergence of novel modes of sexual reproduction in non-bilaterian animals.

Describing gonad development and gametogenesis in southern Africa’s endemic box jellyfish Carybdea branchi (Cubozoa, Carybdeidae)

Information on the reproductive development of species of box jellyfish (class Cubozoa) is poor globally, despite their significance as potent stingers and worrying projections about range expansions. While most species are confined to tropical and subtropical waters, the South African box jellyfish Carybdea branchi is commonly found in the cold-water (especially southern) Benguela ecosystem. Its biology is unknown. Here, we examine reproductive development and describe gametogenesis in this dioecious species. Four and five maturity classes were determined for males and females, respectively, as well as five oocyte developmental stages. Oocyte sizes differed significantly between developmental stages. Mature and immature medusae differed significantly in size, but males and females did not. Individuals matured at approximately 30 mm average bell dimensions. Carybdea branchi displayed gonadal development characteristic of a semelparous organism.

Gonadal histology of box jellyfish (Cnidaria: Cubozoa) reveals variation between internal fertilizing species Alatina alata (Alatinidae) and Copula sivickisi (Tripedaliidae).

Cubozoans (box jellyfish) are gonochoristic cnidarians with distinct reproductive strategies. This comparative histological study examines the gonad organization of Alatina alata and Copula sivickisi, two box jellyfish species that exhibit different modes of internal fertilization. A. alata reproduces via spermcasting aggregations while C. sivickisi reproduces via copulation; in both cases, internal fertilization occurs in the gastrovascular cavity. Herein, we provide the first histological description of subgastric sacs-structures unique to C. sivickisi. Although previously thought to function as sperm storage sacs, our findings reveal that subgastric sacs are nematocyst nests lacking sperm entirely. Conversely, we discovered that velarial spots in C. sivickisi females correspond to actual sperm storage structures. Histological examination of cubozoan sperm packages revealed that while sperm packages from both species have motile flagella, A. alata males produce nonencapsulated sperm bundles (i.e., "spermatozeugmata"), and C. sivickisi males produce encapsulated packages (i.e., "spermatophores"). Our findings corroborate the presence of several types of nematocysts in C. sivickisi embryo strands and spermatophores, and indicate their provenance to be both female and male gonads respectively, as well as subgastric sacs (i.e., nematocyst nests). In contrast to our findings of velarial spots as sperm storages structures in C. sivickisi females, and of nematocysts in the gonads of both sexes, we report that A. alata medusae lack both sperm storage structures and gonadal nematocysts. Finally, we discuss our findings on reproductive morphology of C. sivickisi and A. alata in light of the respective reproductive behavior of these two cubozoan species.

Evidence for an Alternative Mechanism of Toxin Production in the Box Jellyfish Alatina alata.

Cubozoans (box jellyfish) have a reputation as the most venomous animals on the planet. Herein, we provide a review of cubozoan prey capture and digestion informed by the scientific literature. Like all cnidarians, box jellyfish envenomation originates from structures secreted within nematocyte post-Golgi vesicles called nematocysts. When tentacles come in contact with prey or would-be predators, a cocktail of toxins is rapidly deployed from nematocysts via a long spiny tubule that serves to immobilize the target organism. The implication has long been that toxin peptides and proteins making up the venom within the nematocyst capsule are secreted directly by nematocytes during nematogenesis. However, our combined molecular and morphological analysis of the venomous box jellyfish Alatina alata suggests that gland cells with possible dual roles in secreting toxins and toxic-like enzymes are found in the gastric cirri. These putative gland cell assemblages might be functionally important internally (digestion of prey) as well as externally (envenomation) in cubozoans. Despite the absence of nematocysts in the gastric cirri of mature A. alata medusae, this area of the digestive system appears to be the region of the body where venom-implicated gene products are found in highest abundance, challenging the idea that in cnidarians venom is synthesized exclusively in, or nearby, nematocysts. In an effort to uncover evidence for a central area enriched in gland cells associated with the gastric cirri we provide a comparative description of the morphology of the digestive structures of A. alata and Carybdea box jellyfish species. Finally, we conduct a multi-faceted analysis of the gene ontology terms associated with venom-implicated genes expressed in the tentacle/pedalium and gastric cirri, with a particular emphasis on zinc metalloprotease homologs and genes encoding other bioactive proteins that are abundant in the A. alata transcriptome.

A new pygmy species of box jellyfish (Cubozoa: Chirodropida) from sub-tropical Australia

Tropical box jellyfish include some of the world's most venomous animals, leading researchers and the media to wonder whether changes in climate may drive these species into sub-tropical waters. The discovery, therefore, of small box jellyfish in the waterways of the Gold Coast and Sunshine Coast of south-east Queensland raised concern. This pygmy species proved to be new to science, separated from other species in the genusChiropsellaby its very small size; its semi-circular phacellae; very shallow, coalesced gastric saccules; its peculiar, long pedalia where the ‘palm’ is greatly reduced and the non-opposing ‘fingers’ branch off together at the same level; and a knee-like bend of the pedalial canal. The residential canal/river habitat of this species of chirodropid raises the question of whether this area is also suitable for habitation by the larger, more virulent chirodropids such as the so-called ‘deadly box jellyfish’,Chironex fleckeri. This new species,Chiropsella saxonisp. nov., brings the total number of chirodropid species described from Australian waters to five.

Redescription of Alatina alata (Reynaud, 1830) (Cnidaria: Cubozoa) from Bonaire, Dutch Caribbean.

Here we establish a neotype for Alatina alata (Reynaud, 1830) from the Dutch Caribbean island of Bonaire. The species was originally described one hundred and eighty three years ago as Carybdea alata in La Centurie Zoologique-a monograph published by René Primevère Lesson during the age of worldwide scientific exploration. While monitoring monthly reproductive swarms of A. alata medusae in Bonaire, we documented the ecology and sexual reproduction of this cubozoan species. Examination of forty six A. alata specimens and additional archived multimedia material in the collections of the National Museum of Natural History, Washington, DC revealed that A. alata is found at depths ranging from surface waters to 675 m. Additional studies have reported it at depths of up to 1607 m in the tropical and subtropical Atlantic Ocean. Herein, we resolve the taxonomic confusion long associated with A. alata due to a lack of detail in the original description and conflicting statements in the scientific literature. A new cubozoan character, the velarial lappet, is described for this taxon. The complete description provided here serves to stabilize the taxonomy of the second oldest box jellyfish species, and provide a thorough redescription of the species.

106. Molecular Diversity of Box Jellyfish Toxins

Box jellyfish (cubozoans) are renowned for their ability to immobilise and kill prey and inflict painful and debilitating stings to humans by injecting potent venoms from their nematocysts. Chironex fleckeri is the largest species of box jellyfish and its venom produces extremely rapid and potentially life-threatening effects. Advances in box jellyfish toxinology using bioactivity-guided purification methods, tandem mass spectrometry and molecular cloning techniques have revealed that C. fleckeri venom contains a diverse array of proteins that is dominated by a family of abundant high molecular weight venom proteins that are cytolytic, cytotoxic and cause profound cardiovascular collapse in experimental animals. Related toxins with similar biological activities are present in other jellyfish species and comparative analysis of available toxin sequences infers that this expanding family of potent cnidarian toxins forms at least two distinct protein clades. Sequence divergence among family members coupled with experimental evidence suggests there are significant structural variations between clades that may alter their function and target specificity. In this context, an overview of this unique family of protein toxins is presented, including a brief history of their discovery and recent progress in their purification and molecular characterisation primarily from a bioinformatic perspective.

Structure and optics of the eyes of the box jellyfish Chiropsella bronzie

Cubomedusae have a total of 24 eyes of four morphologically different types. Two of these eye types are camera-type eyes (upper and lower lens-eye), while the other two eye types are simpler pigment pit eyes (pit and slit eye). Here, we give a description of the visual system of the box jellyfish species Chiropsella bronzie and the optics of the lens eyes in this species. One aim of this study is to distinguish between general cubozoan features and species-specific features in the layout and optics of the eyes. We find that both types of lens eyes are more severely under-focused in C. bronzie than those in the previously investigated species Tripedalia cystophora. In the lower lens-eye of C. bronzie, blur circles subtend 20 and 52 degrees for closed and open pupil, respectively, effectively removing all but the coarsest structures of the image. Histology reveals that the retina of the lower lens-eye, in addition to pigmented photoreceptors, also contains long pigment-cells, with both dark and white pigment, where the dark pigment migrates on light/dark adaptation. Unlike the upper lens-eye lens of T.cystophora, the same eye in C.bronzie did not display any significant optical power.

Biochemical and molecular characterisation of cubozoan protein toxins

Class Cubozoa includes several species of box jellyfish that are harmful to humans. The venoms of box jellyfish are stored and discharged by nematocysts and contain a variety of bioactive proteins that are cytolytic, cytotoxic, inflammatory or lethal. Although cubozoan venoms generally share similar biological activities, the diverse range and severity of effects caused by different species indicate that their venoms vary in protein composition, activity and potency. To date, few individual venom proteins have been thoroughly characterised, however, accumulating evidence suggests that cubozoan jellyfish produce at least one group of homologous bioactive proteins that are labile, basic, haemolytic and similar in molecular mass (42–46 kDa). The novel box jellyfish toxins are also potentially lethal and the cause of cutaneous pain, inflammation and necrosis, similar to that observed in envenomed humans. Secondary structure analysis and remote protein homology predictions suggest that the box jellyfish toxins may act as α-pore-forming toxins. However, more research is required to elucidate their structures and investigate their mechanism(s) of action. The biological, biochemical and molecular characteristics of cubozoan venoms and their bioactive protein components are reviewed, with particular focus on cubozoan cytolysins and the newly emerging family of box jellyfish toxins.

A New Genus and species of Box Jellyfish (Cubozoa: Carybdeidae) from Tropical Australian Waters

A new genus and species of cubozoan is reported from the Northern Territory and Queensland. It possesses the following autapomorphic characters with respect to other known forms in the Tamoya/Irukandji group of carybdeids: a robust, matchbox-sized body; broad and overhanging pedalial inner wings; laminar-branching velarial canals; and qualitatively and quantatively unique nematocysts. Furthermore, while it shares some characters with other taxa in the group, it is unique in its combination of major morphological characters: like Tamoya, Carukia, Malo and 'Morbakka', it has frown-shaped rhopalial niche ostia; like Carukia, Malo and 'Morbakka', it has rhopalial horns, perradial lappets, and lacks gastric cirri; like Tamoya and 'Morbakka', it has a prominent thorn-shaped upwardpointing diverticulum near the base of the pedalial canal and greatly flared tentacle bases; like Malo and 'Morbakka', it has two rows of nematocyst warts on the perradial lappets; like Malo, the rhopaliar horns are short and broad. Its cnidome comprises Type 4 microbasic p-mastigophores on the tentacles, and spherical isorhizas on the bell. Recent molecular phylogenetic studies place it, along with 'Morbakka', intermediate between the Carukia clade and the Malo clade. It is considered a mild health risk to humans.