Cubozoa e Scyphozoa (Cnidaria: Medusozoa) de águas costeiras do Brasil

As espécies de Cubozoa e Scyphozoa costeiras que ocorrem no Brasil são descritas, com base em espécimes de coleções de museus e exemplares recém-coletados. Chaves de identificação e um glossário também são apresentados. As espécies descritas são: Aurelia sp.; Cassiopea xamachana Bigelow, 1892; Chiropsalmus quadrumanus (Müller, 1859); Chrysaora lactea Eschscholtz, 1829; Drymonema dalmatinum Haeckel, 1880; Linuche unguiculata (Swartz, 1788); Lychnorhiza lucerna Haeckel, 1880; Nausithoe aurea Silveira & Morandini, 1997; Phyllorhiza punctata von Lendenfeld, 1884; Stomolophus meleagris Agassiz, 1862; Tamoya haplonema Müller, 1859 e Tripedalia cystophora Conant, 1897.

Chrysaora plocamia lesson, 1830 (cnidaria, scyphozoa), frente a Pisco, Perú

Observa una generalizada proliferación de medusas, que llegan a formar “blooms” o poblaciones de alta densidad que podrían reemplazar organismos tradicionalmente dominantes en la cadena trófica.

Hydrozoa e Scyphozoa existentes no instituto paulista de oceanografia

Continuing the inventory of the Coelenterate Fauna of the Brazilian coast, 23 species of Hydrozoa and a Scyphomedusa are recorded from different points of the coast aproximately between 22º and 24º lat. S. Of these, 14 species were already known from other points of the coast and the remaining 10 were unknown from this latitude. Two species are here listed as new, they are: Halocordyle fragHis and Calicella gabriellae. 1. - Halocordyle fragilis, Stechow's (1923) correction of the generic name Pennaria has been followed, shows remarkable distinctive specific characters such as: alternate distribution of the cladii which do not lie all in the same plane, they are inserted at random on the hydrocaulus with a tendency towards a spiral dexiotropic distribution, sparse distribution of the pedicels which are alternate and not all located on the same side of the hydrocladium, and, finally, the long, wiry aspect of the colony which is as brittle as light glass. This characteristics are not sufficient, to my belief, to establish a new genus, since the polyps and the gonophores are entirely of the Halocordyle type, but they confer upon the species a very peculiar habitus. 2. - Calicella gabriellae forms erect hydrocauli which are extremely soft and flexuose, with hydrothecate and intermediate internodes. The thecae are deep, cylindrical, with a conical base, there are 10-12 long and narrow opercular valves. The gonangia are small, conical, with a short distal digitiform process. The included sporosac exhibits maturing ova. Dynamena heteroclonta described by Jarvis (1922) as a new species, is here considered as a new form of the very variable species Dynamena quadridentata. Schizotricha billardi nom. nov., is specifically separated from Sch. diaphana (Heller) to which it had been identified up to know. The Brazilian colonies agree with the French Somaliland specimens described by Billard (1904) and they are reunited in a new species named after the French worker. The main difference, between the two mentioned species are: shape and size of the gonothecae, of the thecae and of the nematophores. A description is given of all the species not previously recorded from the Brazilian coast as well as biological observations on Olindias sambaquiensis whose shoals during winter months are very large and may entangle partially the fishermen's nets. Its feeding and swimming habits are described and the species proves to be an excellent laboratory animal both for class and research purposes, for it easily endures long transportation (even up to 12 hours during summer months) as well as unoxygenized acquaria and nevertheless greadily feeds on any animal food.

Characterizations of juvenile stages of some semaeostome Scyphozoa (Cnidaria), with recognition of a new family (Phacellophoridae)

Phacellophora camtschatica has long been assigned to the semaeostome scyphozoan family Ulmaridae. Early stages (scyphistomae, strobilae, ephyrae, postephyrae, and young medusae) of the species were compared with those of several other semaeostomes currently assigned to Ulmaridae, Pelagiidae, and Cyaneidae. Juveniles of P. camtschatica did not strictly conform with characters of those of any of these families, and appeared intermediate between Cyaneidae and Ulmaridae. A new family, Phacellophoridae, is proposed to accommodate P. camtschatica.

Cladistic analysis of the suborder Conulariina Miller and Gurley, 1896 (Cnidaria, Scyphozoa; Vendian-Triassic)

Results of a cladistic analysis of the suborder Conulariina Miller and Gurley, 1896, a major extinct (Vendian-Triassic) group of scyphozoan cnidarians, are presented. The analysis sought to test whether the three conulariid subfamilies (Conulariinae Walcott, 1886, Paraconulariinae Sinclair, 1952 and Ctenoconulariinae Sinclair, 1952) recognized in the Treatise on Invertebrate Paleontology ( TIP) are monophyletic. A total of 17 morphological characters were scored for 16 ingroup taxa, namely the genera Archaeoconularia, Baccaconularia, Climacoconus, Conularia, Conulariella, Conularina, Ctenoconularia, Eoconularia, Glyptoconularia, Metaconularia, Notoconularia, Paraconularia, Pseudoconularia, Reticulaconularia, Teresconularia and Vendoconularia. The extant medusozoan taxa Cubozoa, Stauromedusae, Coronatae and Semaeostomeae served as outgroups. Unweighted analysisof the data matrix yielded 1057 trees, and successive weighting analysis resulted in one of the 1057 original trees. The ingroup is monophyletic with two autapomorphies: (1) the quadrate geometry of the oral region; and (2) the presence of a mineralized (phosphatic) periderm. Within the ingroup, the clade (Vendoconularia, Teresconularia, Conularina, Eoconularia) is supported by the sinusoidal longitudinal geometry of the transverse ridges, and the much larger clade (Baccaconularia, Glyptoconularia, Metaconularia, Pseudoconularia, Conularia, Ctenoconularia, Archaeoconularia, Notoconularia, Climacoconus, Paraconularia, Reticulaconularia) is supported by the presence of external tubercles, which, however, were lost in the clade (Notoconularia, Climacoconus, Paraconularia, Reticulaconularia). As proposed by Van Iten et al. (2000), the clade (Notoconularia, Climacoconus, Paraconularia, Reticulaconularia) is supported by the termination and alternation of the transverse ribs in the corner sulcus. The previously recognized subfamilies Conulariinae, Paraconulariinae and Ctenoconulariinae were not recovered from this analysis. The diagnostic features of Conulariinae (continuation of the transverse ornament across the corner sulcus and lack of carinae) and Ctenoconulariinae ( presence of carinae) are symplesiomorphic or homoplastic, and Paraconulariinae is polyphyletic. The families Conulariellidae Kiderlen, 1937 and Conulariopsidae Sugiyama, 1942, also recognized in the TIP, are monogeneric, and since they provide no additional phylogenetic information, should be abandoned.

Food resources influencing the asexual reproductive cycle of coronate Scyphozoa

The study of the strobilation process, a feature unique in the class Scyphozoa, is an issue that helps understanding the patterns of asexual reproduction in sessile invertebrates. Many inducers of asexual reproduction are known for scyphozoans. However, the influence of food resources on the strobilation of Coronate Scyphozoa has never been tested. WO observed strobilation of a large number of polyps of Nausithoe aurea, from a wide sampling area along the South Atlantic coast of Brazil, through the administration of controlled number of hatched nauplii of Artemia franciscana under a previous tested starvation and feeding protocol. The number of strobilations between and within groups varied and the fate and shape of strobilation deviated from the biology reported in the original description. Artificial seawater was used to reduce the influence of dissolved organic matter as likely important alternative nourishment.

Cladistic analysis of the suborder Conulariina Miller and Gurley, 1896 (Cnidaria, Scyphozoa; Vendian-Triassic)

Results of a cladistic analysis of the suborder Conulariina Miller and Gurley, 1896, a major extinct (Vendian-Triassic) group of scyphozoan cnidarians, are presented. The analysis sought to test whether the three conulariid subfamilies (Conulariinae Walcott, 1886, Paraconulariinae Sinclair, 1952 and Ctenoconulariinae Sinclair, 1952) recognized in the Treatise on Invertebrate Paleontology ( TIP) are monophyletic. A total of 17 morphological characters were scored for 16 ingroup taxa, namely the genera Archaeoconularia, Baccaconularia, Climacoconus, Conularia, Conulariella, Conularina, Ctenoconularia, Eoconularia, Glyptoconularia, Metaconularia, Notoconularia, Paraconularia, Pseudoconularia, Reticulaconularia, Teresconularia and Vendoconularia. The extant medusozoan taxa Cubozoa, Stauromedusae, Coronatae and Semaeostomeae served as outgroups. Unweighted analysisof the data matrix yielded 1057 trees, and successive weighting analysis resulted in one of the 1057 original trees. The ingroup is monophyletic with two autapomorphies: (1) the quadrate geometry of the oral region; and (2) the presence of a mineralized (phosphatic) periderm. Within the ingroup, the clade (Vendoconularia, Teresconularia, Conularina, Eoconularia) is supported by the sinusoidal longitudinal geometry of the transverse ridges, and the much larger clade (Baccaconularia, Glyptoconularia, Metaconularia, Pseudoconularia, Conularia, Ctenoconularia, Archaeoconularia, Notoconularia, Climacoconus, Paraconularia, Reticulaconularia) is supported by the presence of external tubercles, which, however, were lost in the clade (Notoconularia, Climacoconus, Paraconularia, Reticulaconularia). As proposed by Van Iten et al. (2000), the clade (Notoconularia, Climacoconus, Paraconularia, Reticulaconularia) is supported by the termination and alternation of the transverse ribs in the corner sulcus. The previously recognized subfamilies Conulariinae, Paraconulariinae and Ctenoconulariinae were not recovered from this analysis. The diagnostic features of Conulariinae (continuation of the transverse ornament across the corner sulcus and lack of carinae) and Ctenoconulariinae ( presence of carinae) are symplesiomorphic or homoplastic, and Paraconulariinae is polyphyletic. The families Conulariellidae Kiderlen, 1937 and Conulariopsidae Sugiyama, 1942, also recognized in the TIP, are monogeneric, and since they provide no additional phylogenetic information, should be abandoned.

Distribuição e validade taxonômica do gênero Chrysaora (Cnidaria; Scyphozoa) na América do Sul

Pós-graduação em Biociências - FCLAS

Discovery and redescription of type material of Nausithoe simplex (Kirkpatrick, 1890), comb. nov (Cnidaria: Scyphozoa: Coronatae: Nausithoidae) from the North Atlantic

With discovery and examination of type specimens in the Natural History Museum, London, UK, we reassign Stephanoscyphistoma simplex (Kirkpatrick, 1890) to the genus Nausithoe Kolliker, 1853, as Nausithoe simplex, comb. nov., and designate a lectotype for the species. Use of morphometric measurements is considered important in coronate systematics, but key features also include the unique whorl of internal cusps and the shape of these cusps. All previous records of N. simplex must be re-evaluated, taking into consideration the morphology of these internal cusps.

Molecules Clarify a Cnidarian Life Cycle - The ""Hydrozoan'' Microhydrula limopsicola Is an Early Life Stage of the Staurozoan Haliclystus antarcticus

Background: Life cycles of medusozoan cnidarians vary widely, and have been difficult to document, especially in the most recently proposed class Staurozoa. However, molecular data can be a useful tool to elucidate medusozoan life cycles by tying together different life history stages. Methodology/Principal Findings: Genetic data from fast-evolving molecular markers (mitochondrial 16S, nuclear ITS1, and nuclear ITS2) show that animals that were presumed to be a hydrozoan, Microhydrula limopsicola (Limnomedusae, Microhydrulidae), are actually an early stage of the life cycle of the staurozoan Haliclystus antarcticus (Stauromedusae, Lucernariidae). Conclusions/Significance: Similarity between the haplotypes of three markers of Microhydrula limopsicola and Haliclystus antarcticus settles the identity of these taxa, expanding our understanding of the staurozoan life cycle, which was thought to be more straightforward and simple. A synthetic discussion of prior observations makes sense of the morphological, histological and behavioral similarities/congruence between Microhydrula and Haliclystus. The consequences are likely to be replicated in other medusozoan groups. For instance we hypothesize that other species of Microhydrulidae are likely to represent life stages of other species of Staurozoa.45

Naming the Bonaire banded box jelly, Tamoya ohboya, n. sp. (Cnidaria: Cubozoa: Carybdeida: Tamoyidae)

A new species of cubozoan jellyfish has been discovered in shallow waters of Bonaire, Netherlands ( Dutch Caribbean). Thus far, approximately 50 sightings of the species, known commonly as the Bonaire banded box jelly, are recorded, and three specimens have been collected. Three physical encounters between humans and the species have been reported. Available evidence suggests that a serious sting is inflicted by this medusa. To increase awareness of the scientific disciplines of systematics and taxonomy, the public has been involved in naming this new species. The Bonaire banded box jelly, Tamoya ohboya, n. sp., can be distinguished from its close relatives T. haplonema from Brazil and T. sp. from the southeastern United States by differences in tentacle coloration, cnidome, and mitochondrial gene sequences. Tamoya ohboya n. sp. possesses striking dark brown to reddish-orange banded tentacles, nematocyst warts that densely cover the animal, and a deep stomach. We provide a detailed comparison of nematocyst data from Tamoya ohboya n. sp., T. haplonema from Brazil, and T. sp. from the Gulf of Mexico.

Taxonomic review of Haliclystus antarcticus Pfeffer, 1889 (Stauromedusae, Staurozoa, Cnidaria), with remarks on the genus Haliclystus Clark, 1863

Difficulties concerning the taxonomy of stauromedusae are long known, and there is a clear need for taxonomic revision of the genus Haliclystus, as well as the reevaluation of some species. Haliclystus antarcticus Pfeffer, 1889 is recorded from Admiralty Bay, King George Island, Antarctic Peninsula. Due to the lack of detailed information on this species, we provide a redescription, presenting new data on the cnidome, morphometry, geographical distribution and intraspecific variation. Based on these characters, we propose that our specimens and Haliclystus auricula from Chile and Argentina are synonymous and should be classified as H. antarcticus. We also review the worldwide distribution of the genus Haliclystus Clark, 1863 and discuss taxonomic issues, concluding that some characters traditionally used in the taxonomy of the group should be used cautiously.

Major developments in conulariid research: problems of interpretation and future perspectives

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Reassessment of the phylogenetic position of conulariids (?Ediacaran-Triassic) within the subphylum medusozoa (Phylum Cnidaria)

Fossil taxa of uncertain phytogenetic affinities can play a crucial role in the analysis of character evolution within major extant groups. Marques & Collins (2004) concluded that conulariids (?Ediacaran-Triassic) are an extinct group of medusozoan cnidarians most closely related to Stauromedusae. However, only six of the 87 characters used by these authors can be observed in conulariid fossils. Rescoring the character states of conulariids in a conservative manner yields a new hypothesis for the phylogenetic position of conulariids, namely that they are the sister group of the scyphozoan order Coronatae rather than Stauromedusae, which is revealed as the earliest diverging lineage of Medusozoa. This new hypothesis also implies several different sequences of character evolution within Cnidaria. Specifically, the presence of a periderm completely covering the polyp in conutariids and coronates appears to be derived within Scyphozoa. Strobilation appears to be a synapomorphy uniting conulariids, Coronatae, Rhizostomeae and Semaeostomeae. This result supports the controversial interpretation of one exceptionally preserved conulariid that potentially shows that these animals produced ephyrae by strobilation. Finally, the pelagic adult medusa stage and the giant fibre nerve net appear to be features that are derived within Medusozoa.

Animais aquáticos de importância médica no Brasil

The injuries caused by venomous and poisonous aquatic animals may provoke important morbidity in the victim. The cnidarians (jellyfishes, especially cubomedusas and Portuguese-Man-of-War) caused nearly 25% of 236 accidents by marine animals, while sea urchins were responsible for about 50% and catfish, stingrays and scorpionfish nearly 25%). In freshwater, stingrays and catfish cause injuries with a very similar mechanism to the poisoning and the effects of the toxins of marine species. In a series of about 200 injuries observed among freshwater fishermen, nearly 40% were caused by freshwater catfish, 5% freshwater stingrays and 55% by traumatogenic fish, such as piranhas and trairas. The author presents the aquatic animals that cause injuries to humans in Brazil, the clinical aspects of the envenoming and the first measures for the control of the severe pain observed mainly in the accidents caused by cnidarians and venomous fishes.