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1.
Neurocrit Care ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589692

RESUMEN

BACKGROUND: Standard treatment for eligible patients presenting with acute ischemic stroke (AIS) is thrombolysis with tissue plasminogen activators alteplase or tenecteplase. Current guidelines recommend monitoring patients in an intensive care unit (ICU) for 24 h after thrombolytic therapy. However, recent studies have questioned the need for prolonged ICU monitoring. This retrospective cohort study aims to identify potential candidates for early transition to a lower level of care by assessing risk factors for neurological deterioration, symptomatic intracranial hemorrhage (sICH), or need for ICU intervention within 24 h post-thrombolysis. METHODS: This retrospective cohort study included adult patients 18 years and older with AIS who received thrombolysis. Patients were excluded if they were transferred to another facility, if they were transitioned to comfort care or hospice care within 24 h, or if they lacked imaging and National Institutes of Health Stroke Scale (NIHSS) score data. The primary end point was incidence of sICH between 0-12 and 12-24 h. Secondary end points included the need for ICU intervention and rates of neurological deterioration. RESULTS: The analysis included 204 patients who received the full dose of alteplase. Among them, ten patients (4.9%) developed sICH, with the majority (n = 7) occurring within 12 h post-thrombolysis. Sixty-two patients required ICU interventions within 12 h compared with four patients after 12 h. Twenty-four patients had neurological deterioration within 12 h, and seven patients had neurological deterioration after 12 h. Multivariable analysis identified mechanical thrombectomy and increased blood pressure at presentation as predictors of ICU need beyond 12 h post-thrombolysis. CONCLUSIONS: Our study demonstrates that sICH, neurological deterioration, and need for ICU intervention rarely occur beyond 12 h after thrombolytic administration. Patients presenting with blood pressures < 140/90 mm Hg, NIHSS scores < 10, and not undergoing mechanical thrombectomy may be best candidates for early de-escalation. Larger prospective studies are needed to more fully evaluate the safety, feasibility, and financial impact of early transition out of the ICU.

2.
Mol Phylogenet Evol ; 182: 107732, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36781031

RESUMEN

Symbioses play important roles in forming the structural and distributional patterns of marine diversity. Understanding how interspecies interactions through symbioses contribute to biodiversity is an essential topic. Host switching has been considered as one of the main drivers of diversification in symbiotic systems. However, its process and patterns remain poorly investigated in the marine realm. Hexacoral species of the order Zoantharia (=zoantharians) are often epizoic on other marine invertebrates and generally use specific taxa as hosts. The present study investigates the patterns of host switching and the diversification history of zoantharians based on the most comprehensive molecular phylogenetic analyses to date, using sequences from three mitochondrial and three nuclear markers from representatives of 27 of 29 genera. Our results indicate that symbiotic zoantharians, in particular those within suborder Macrocnemina, diversified through repeated host switching. In addition, colonization of new host taxa appears to have driven morphological and ecological specialization in zoantharians. These findings have important implications for understanding the role of symbioses in the morphological and ecological evolution of marine invertebrates.


Asunto(s)
Antozoos , Animales , Filogenia , Antozoos/genética , Núcleo Celular , Biodiversidad , Simbiosis/genética
3.
Glob Chang Biol ; 29(12): 3318-3330, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37020174

RESUMEN

Scientists and managers rely on indicator taxa such as coral and macroalgal cover to evaluate the effects of human disturbance on coral reefs, often assuming a universally positive relationship between local human disturbance and macroalgae. Despite evidence that macroalgae respond to local stressors in diverse ways, there have been few efforts to evaluate relationships between specific macroalgae taxa and local human-driven disturbance. Using genus-level monitoring data from 1205 sites in the Indian and Pacific Oceans, we assess whether macroalgae percent cover correlates with local human disturbance while accounting for factors that could obscure or confound relationships. Assessing macroalgae at genus level revealed that no genera were positively correlated with all human disturbance metrics. Instead, we found relationships between the division or genera of algae and specific human disturbances that were not detectable when pooling taxa into a single functional category, which is common to many analyses. The convention to use percent cover of macroalgae as an indication of local human disturbance therefore likely obscures signatures of local anthropogenic threats to reefs. Our limited understanding of relationships between human disturbance, macroalgae taxa, and their responses to human disturbances impedes the ability to diagnose and respond appropriately to these threats.


Asunto(s)
Antozoos , Algas Marinas , Animales , Humanos , Arrecifes de Coral , Ecosistema , Algas Marinas/fisiología , Antozoos/fisiología , Océano Pacífico
4.
Syst Biol ; 71(4): 1009-1022, 2022 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-34469579

RESUMEN

Phylogenetic analyses may suffer from multiple sources of error leading to conflict between genes and methods of inference. The evolutionary history of the mollusc clade Vetigastropoda makes them susceptible to these conflicts, their higher level phylogeny remaining largely unresolved. Originating over 350 Ma, vetigastropods were the dominant marine snails in the Paleozoic. Multiple extinction events and new radiations have resulted in both very long and very short branches and a large extant diversity of over 4000 species. This is the perfect setting of a hard phylogenetic question in which sources of conflict can be explored. We present 41 new transcriptomes across the diversity of vetigastropods (62 terminals total), and provide the first genomic-scale phylogeny for the group. We find that deep divergences differ from previous studies in which long branch attraction was likely pervasive. Robust results leading to changes in taxonomy include the paraphyly of the order Lepetellida and the family Tegulidae. Tectinae subfam. nov. is designated for the clade comprising Tectus, Cittarium, and Rochia. For two early divergences, topologies disagreed between concatenated analyses using site heterogeneous models versus concatenated partitioned analyses and summary coalescent methods. We investigated rate and composition heterogeneity among genes, as well as missing data by locus and by taxon, none of which had an impact on the inferred topologies. We also found no evidence for ancient introgression throughout the phylogeny. We further tested whether uninformative genes and over-partitioning were responsible for this discordance by evaluating the phylogenetic signal of individual genes using likelihood mapping, and by analyzing the most informative genes with a full multispecies coalescent (MSC) model. We find that most genes are not informative at the two conflicting nodes, but neither this nor gene-wise partitioning are the cause of discordant results. New method implementations that simultaneously integrate amino acid profile mixture models and the MSC might be necessary to resolve these and other recalcitrant nodes in the Tree of Life. [Fissurellidae; Haliotidae; likelihood mapping; multispecies coalescent; phylogenetic signal; phylogenomic conflict; site heterogeneity; Trochoidea.].


Asunto(s)
Evolución Biológica , Genoma , Animales , Genómica , Filogenia , Caracoles/genética
5.
Environ Microbiol ; 24(3): 1308-1325, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34708512

RESUMEN

Terpios hoshinota is an aggressive, space-competing sponge that kills various stony corals. Outbreaks of this species have led to intense damage to coral reefs in many locations. Here, the first large-scale 16S rRNA gene survey across three oceans revealed that bacteria related to the taxa Prochloron, Endozoicomonas, SAR116, Ruegeria, and unclassified Proteobacteria were prevalent in T. hoshinota. A Prochloron-related bacterium was the most dominant and prevalent cyanobacterium in T. hoshinota. The complete genome of this uncultivated cyanobacterium and pigment analysis demonstrated that it has phycobiliproteins and lacks chlorophyll b, which is inconsistent with the definition of Prochloron. Furthermore, the cyanobacterium was phylogenetically distinct from Prochloron, strongly suggesting that it should be a sister taxon to Prochloron. Therefore, we proposed this symbiotic cyanobacterium as a novel species under the new genus Candidatus Paraprochloron terpiosi. Comparative genomic analyses revealed that 'Paraprochloron' and Prochloron exhibit distinct genomic features and DNA replication machinery. We also characterized the metabolic potentials of 'Paraprochloron terpiosi' in carbon and nitrogen cycling and propose a model for interactions between it and T. hoshinota. This study builds a foundation for the study of the T. hoshinota microbiome and paves the way for better understanding of ecosystems involving this coral-killing sponge.


Asunto(s)
Antozoos , Cianobacterias , Microbiota , Poríferos , Animales , Antozoos/microbiología , Arrecifes de Coral , Cianobacterias/metabolismo , Poríferos/genética , Prevalencia , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/metabolismo , Simbiosis
6.
Proc Biol Sci ; 289(1984): 20221576, 2022 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-36196541

RESUMEN

Colour patterns in fish are often used as an important medium for communication. Anemonefish, characterized by specific patterns of white bars, inhabit host anemones and defend the area around an anemone as their territory. The host anemone is used not only by the anemonefish, but also by other fish species that use anemones as temporary shelters. Anemonefish may be able to identify potential competitors by their colour patterns. We first examined the colour patterns of fish using host anemones inhabited by Amphiprion ocellaris as shelter and compared them with the patterns of fish using surrounding scleractinian corals. There were no fish with bars sheltering in host anemones, although many fish with bars were found in surrounding corals. Next, two fish models, one with white bars and the other with white stripes on a black background, were presented to an A. ocellaris colony. The duration of aggressive behaviour towards the bar model was significantly longer than that towards the stripe model. We conclude that differences in aggressive behaviour by the anemonefish possibly select the colour patterns of cohabiting fish. This study indicates that colour patterns may influence not only intraspecific interactions but also interspecific interactions in coral reef ecosystems.


Asunto(s)
Anemone , Antozoos , Anémonas de Mar , Animales , Color , Arrecifes de Coral , Ecosistema , Peces , Simbiosis
7.
Syst Biol ; 70(4): 635-647, 2021 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-33507310

RESUMEN

Anthozoan cnidarians (corals and sea anemones) include some of the world's most important foundation species, capable of building massive reef complexes that support entire ecosystems. Although previous molecular phylogenetic analyses have revealed widespread homoplasy of the morphological characters traditionally used to define orders and families of anthozoans, analyses using mitochondrial genes or rDNA have failed to resolve many key nodes in the phylogeny. With a fully resolved, time-calibrated phylogeny for 234 species constructed from hundreds of ultraconserved elements and exon loci, we explore the evolutionary origins of the major clades of Anthozoa and some of their salient morphological features. The phylogeny supports reciprocally monophyletic Hexacorallia and Octocorallia, with Ceriantharia as the earliest diverging hexacorals; two reciprocally monophyletic clades of Octocorallia; and monophyly of all hexacoral orders with the exception of the enigmatic sea anemone Relicanthus daphneae. Divergence dating analyses place Anthozoa in the Cryogenian to Tonian periods (648-894 Ma), older than has been suggested by previous studies. Ancestral state reconstructions indicate that the ancestral anthozoan was a solitary polyp that had bilateral symmetry and lacked a skeleton. Colonial growth forms and the ability to precipitate calcium carbonate evolved in the Ediacaran (578 Ma) and Cambrian (503 Ma) respectively; these hallmarks of reef-building species have subsequently arisen multiple times independently in different orders. Anthozoans formed associations with photosymbionts by the Devonian (383 Ma), and photosymbioses have been gained and lost repeatedly in all orders. Together, these results have profound implications for the interpretation of the Precambrian environment and the early evolution of metazoans.[Bilateral symmetry; coloniality; coral; early metazoans; exon capture; Hexacorallia; Octocorallia photosymbiosis; sea anemone; ultraconserved elements.].


Asunto(s)
Antozoos , Anémonas de Mar , Animales , Antozoos/genética , Ecosistema , Genes Mitocondriales , Filogenia , Anémonas de Mar/genética
8.
Parasitology ; : 1-23, 2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-35357289

RESUMEN

The taxonomy of species of Bivesicula Yamaguti, 1934 is analysed for samples from holocentrid, muraenid and serranid fishes from Japan, Ningaloo Reef (Western Australia), the Great Barrier Reef (Queensland), New Caledonia and French Polynesia. Analysis of three genetic markers (cox1 mtDNA, ITS2 and 28S rDNA) identifies three strongly supported clades of species and suggests that Bivesicula as presently recognized is not monophyletic. On the basis of combined morphological, molecular and biological data, 10 species are distinguished of which five are proposed as new. Bivesicula Clade 1 comprises seven species of which three are effectively morphologically cryptic relative to each other; all seven infect serranids and four also infect holocentrids. Bivesicula Clade 2 comprises three species of which two are effectively morphologically cryptic relative to each other; all three infect serranids and one also infects a muraenid. Bivesicula Clade 3 comprises two known species from apogonids and a pomacentrid, and forms a clade with species of Paucivitellosus Coil, Reid & Kuntz, 1965 to the exclusion of other Bivesicula species. Taxonomy in this genus is made challenging by the combination of low resolving power of ribosomal markers, the existence of regional cox1 mtDNA populations, exceptional and unpredictable host-specificity and geographical distribution, and significant host-induced morphological variation.

9.
Zoolog Sci ; 39(5): 477-488, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36205369

RESUMEN

Among family Zoanthidae (Anthozoa: Hexacorallia: Zoantharia), Zoanthus and Isaurus are widespread benthos on coral reefs, but the reproductive biology of both genera is generally unknown. Accordingly, sexual reproduction of two Zoanthidae species in Japan, Zoanthus kuroshio in Okinawa, and Isaurus tuberculatus in Okinawa and Kochi, was investigated by annual sampling. Between 2012 and 2013, polyps of tagged colonies of Z. kuroshio and I. tuberculatus were sampled monthly, and gonads in mesenteries were examined under a stereomicroscope. In Z. kuroshio, sizes of oocytes were estimated and in situ spawning observations were conducted at night at Okinawa sites. Monthly sampling indicated that gametogenesis periods of both species in Okinawa were from May to August, and oogenesis set in earlier than spermatogenesis, and thus both species can be considered protogynous functional hermaphrodites. On the other hand, I. tuberculatus in Kochi had hermaphroditic polyps in July and August. Notably, fertile colonies of Z. kuroshio were not only hermaphrodites but also included exclusively male and female colonies. Overall, four sexual types were identified in Z. kuroshio: male, female, functional protogynous hermaphrodites, and unclassified sterile colonies. In situ gamete release of Z. kuroshio was observed in August 2012 and July to August 2013. First spawning of the year occurred 1 day after the new moon; colonies shed their bundles 3.5-4 h after sunset. We speculate that lunar phase and time after sunset influence spawning timing in Z. kuroshio. Basic knowledge on sexual reproduction of Zoanthidae is critically needed to better understand the basic biology of these benthic cnidarians.


Asunto(s)
Antozoos , Animales , Arrecifes de Coral , Femenino , Gametogénesis , Japón , Masculino , Reproducción
10.
J Fish Biol ; 100(1): 40-50, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34590316

RESUMEN

The mutualistic relationships between anemonefish (Amphiprion; Pomacentridae) and host sea anemones are well known, but host anemones are also used as shelter by damselfish (Pomacentridae), wrasses (Labridae) and cardinalfish (Apogonidae). The threespot dascyllus Dascyllus trimaculatus (Pomacentridae) is known to live on or near host anemones in their immature phase. Nonetheless, detailed studies on the use of host anemones by other fish species have not yet been conducted. To understand the factors that influence the use of host anemones by other fish species, this study investigated the fish biota around host anemones in the Ryukyu Archipelago. Other than Amphiprion spp. and D. trimaculatus, 10 additional species of fish (9 species of damselfish and 1 species of cardinalfish) were confirmed to temporarily use host anemones as shelter, and five species of wrasse including Labroides dimidiatus came to clean anemonefish. Logistic regression analyses (independent variable: presence or absence of other species of fish; dependent variables: anemonefish aggressiveness, size of host anemone, number of D. trimaculatus) indicated that the size of host anemones is important for the presence of fish, both in species using the anemone as temporary shelter and in cleaner species. Large host anemones can provide shelter and food resources for other species of coral reef fish as well as for anemonefish.


Asunto(s)
Perciformes , Anémonas de Mar , Animales , Arrecifes de Coral , Peces , Simbiosis
11.
Zoolog Sci ; 38(5): 466-480, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34664922

RESUMEN

Symbioses between invertebrates are common in the ocean although usually the diversity and specificity of their interactions are not well understood. Parazoanthidae (Cnidaria: Anthozoa: Zoantharia) is one of the most diverse zoantharian families in terms of numbers of genera and species. Species in this family are commonly associated with various other invertebrates that they utilize as their substrate. Previous studies have re-organized the taxonomy of Parazoanthidae and revealed a strong specificity between many parazoanthid species and genera and their substrates. However, our understanding of the species diversity of Parazoanthidae is far from complete, as parazoanthids are often overlooked in sampling surveys. In this study, we establish three subgenera under the genus Umimayanthus Montenegro, Sinniger, and Reimer, 2015; the nominotypical Umimayanthus, Paraumimayanthus subgen nov., and Gorgoniazoanthus subgen. nov., based on the finding of a new species, Umimayanthus (Gorgoniazoanthus) kanabou sp. nov., associated with the sea-whip gorgonian Ellisella sp. from approximately 30 m depth in shallow mesophotic coral reef communities in Oura Bay on Okinawajima Island and in Oshima Strait near Amami-Oshima Island, in the Ryukyu Islands, southern Japan. We additionally report on gastropods and crustaceans observed in association with U. kanabou, and these species are thought to potentially prey upon the zoantharians or on gorgonian polyps. Umimayanthus kanabou is phylogenetically closely related to congeneric sponge-associated Umimayanthus spp., further supporting the recent hypothesis that substrate preferences may change during the evolutionary history of zoantharians.


Asunto(s)
Antozoos/anatomía & histología , Antozoos/clasificación , Especificidad de la Especie , Animales , Antozoos/genética , Crustáceos , Ecosistema , Gastrópodos , Japón , Filogenia , Análisis de Secuencia de ADN
12.
Mol Phylogenet Evol ; 131: 233-244, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30471843

RESUMEN

The order Pennatulacea, commonly known as sea pens, are colony-forming benthos belonging within subclass Octocorallia (Anthozoa, Cnidaria). Sea pens are found worldwide from shallow to deep waters, and they are important components in sandy and muddy environments. Thus far, there has been only one molecular study focusing on the phylogenetic relationships within the order Pennatulacea, which mainly treated deep-sea species, and thus information on shallow water species is still lacking. On a regional scale, the diversity of sea pens in the northwestern Pacific, including Japan and Palau, has not been well investigated. In this research, we aimed to: (1) more accurately resolve the phylogenetic relationships of sea pens with the inclusion of shallow water species, and (2) obtain a better understanding of the diversity of sea pens in Japan and Palau. Specimens were collected by SCUBA and dredging from the Ryukyu Islands in southern Japan, and from mainland Japan and Palau, and identified to at least the genus level by their morphological traits. Construction of phylogenetic trees with concatenated sequences including the mitochondrial mutS-like protein DNA mismatch repair gene mtMutS and the NADH dehydrogenase subunit 2 ND2 region were performed. The p-distances of mtMutS were calculated for estimation of species number following McFadden et al. (2011). Molecular data for 12 families and 20 genera of sea pens were used in this study. This most comprehensive study including shallow water taxa provided us with more knowledge of phylogenetic relationships. The resulting phylogenetic trees showed a topology distinguished by four large clades (clades 1-4). Families Veretillidae and Echinoptilidae are shown as not the earliest-diverging taxa. Virgulariidae and Scleroptilidae are shown as polyphyletic groups, and our results reconfirm that families Pennatulidae, Kophobelemnidae and Umbellulidae are not monophyletic groups. Overall, we collected and examined an estimated 18 species from the Ryukyu Islands, 16 species from mainland Japan, and five species from Palau. Some of these specimens represented new records from Ryukyu Islands and Palau. Previous records of these sea pens did not exist likely due to a lack of diversity research in sandy and muddy areas. These results demonstrate that many sea pens discoveries likely remain in shallow waters of the Pacific.


Asunto(s)
Antozoos/clasificación , Organismos Acuáticos/clasificación , Biodiversidad , Filogenia , Animales , Geografía , Japón , Funciones de Verosimilitud , Océano Pacífico , Especificidad de la Especie
13.
Mol Phylogenet Evol ; 130: 304-314, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30316946

RESUMEN

The Family Hydrozoanthidae are macrocnemic zoantharians, however their phylogenetic position is closer to brachycnemic zoantharians than to other macrocnemic zoantharians. Previous studies have indicated the presence of undescribed Hydrozoanthidae species from various locations in the Indo-Pacific Ocean. In this study, two new Hydrozoanthidae species, Aenigmanthus segoi gen. n., sp. n. and Hydrozoanthus sils sp. n., are described from Japanese and Palauan waters based on combined morphological and molecular phylogenetic analyses utilizing multiple genetic markers. Additionally, Hydrozoanthidae consists of species with an obligate epizoic relationship with hydroids (Hydrozoanthus) and of species with facultative epizoic relationships (Aenigmanthus gen. n. and Terrazoanthus). Results of ancestral state reconstruction analyses indicate that Hydrozoanthus gained obligate epizoic relationships in their evolutionary history perhaps due to structural differences of host invertebrates.


Asunto(s)
Antozoos/clasificación , Filogenia , Animales , Antozoos/genética , Ecosistema , Funciones de Verosimilitud , Océano Pacífico , Palau , Especificidad de la Especie
14.
Mol Phylogenet Evol ; 139: 106526, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31158486

RESUMEN

The clownfish-sea anemone symbiosis has been a model system for understanding fundamental evolutionary and ecological processes. However, our evolutionary understanding of this symbiosis comes entirely from studies of clownfishes. A holistic understanding of a model mutualism requires systematic, biogeographic, and phylogenetic insight into both partners. Here, we conduct the largest phylogenetic analysis of sea anemones (Order Actiniaria) to date, with a focus on expanding the biogeographic and taxonomic sampling of the 10 nominal clownfish-hosting species. Using a combination of mtDNA and nuDNA loci we test (1) the monophyly of each clownfish-hosting family and genus, (2) the current anemone taxonomy that suggests symbioses with clownfishes evolved multiple times within Actiniaria, and (3) whether, like the clownfishes, there is evidence that host anemones have a Coral Triangle biogeographic origin. Our phylogenetic reconstruction demonstrates widespread poly- and para-phyly at the family and genus level, particularly within the family Stichodactylidae and genus Stichodactyla, and suggests that symbioses with clownfishes evolved minimally three times within sea anemones. We further recover evidence for a Tethyan biogeographic origin for some clades. Our data provide the first evidence that clownfish and some sea anemone hosts have different biogeographic origins, and that there may be cryptic species of host anemones. Finally, our findings reflect the need for a major taxonomic revision of the clownfish-hosting sea anemones.


Asunto(s)
Filogenia , Anémonas de Mar/clasificación , Anémonas de Mar/genética , Simbiosis/fisiología , Animales , Antozoos/fisiología , Evolución Biológica , ADN Mitocondrial/genética , Modelos Biológicos
15.
Zoolog Sci ; 36(3): 259-265, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-31251495

RESUMEN

From previous research, it is known that hermit crabs predominantly dwell in vacated gastropod shells. Several epibiotic taxa are known to live on gastropod shells inhabited by hermit crabs, including some species of the zoantharian genus Epizoanthus. Although many previous taxonomic studies have focused on hermit-crab-associated Epizoanthus species, and have resulted in the description of several species, gastropod-associated species have received comparatively much less attention. At least five Epizoanthus species associated with gastropods have been formally described, but some species have not been found or examined since their original description. In Japan, specimens on the gastropod mollusk Guildfordia triumphans have been found and examined in previous studies, but no formal taxonomic conclusions were made. In this study, we formally describe Epizoanthus rinbou sp. n. from southern Japan based on molecular phylogenetic analyses combined with morphological observations. Epizoanthus rinbou sp. n. is located within an Epizoanthus clade consisting of species associated with gastropods, hermit crabs, sea urchins, and barnacles, as well as non-associated Epizoanthus species. The present study highlights the utility of molecular phylogeny for understanding the diversity and relationships of gastropod-associated Epizoanthus species.


Asunto(s)
Cnidarios/clasificación , Cnidarios/genética , Gastrópodos/fisiología , Exoesqueleto , Animales , Cnidarios/fisiología , Evolución Molecular , Filogenia
17.
Zoolog Sci ; 35(4): 321-329, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30079838

RESUMEN

Tropical and subtropical shallow benthic marine communities are highly diverse and balanced systems that constitute an important natural resource. Knowledge of the genetic diversity, connectivity and reproduction mode of each population is critical to understanding the fate of whole assemblages in times of disturbances. Importantly, the capability of populations to adapt to environmental challenges will be crucial to determining their survival. Here, we report on the population structure of the common reef zoantharian Zoanthus sansibaricus in the northwestern Pacific, by examining populations at three different locations in southern Japan using five highly variable microsatellite markers. Analyses of a population at the species' northern distribution limit combined with analyses of two subtropical populations suggest that habitat characteristics and ocean currents influence the connectivity and genetic diversity of this species. Our findings emphasize the adaptive ability of Z. sansibaricus to different environmental conditions and may help explain the wide distribution and generalist nature of this species.


Asunto(s)
Distribución Animal , Antozoos/genética , Antozoos/fisiología , Arrecifes de Coral , Animales , Variación Genética , Japón , Repeticiones de Microsatélite , Filogenia , Especificidad de la Especie
18.
Zoolog Sci ; 35(2): 123-133, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29623790

RESUMEN

Millepora (Cnidaria: Hydrozoa: Milleporidae) spp. are distributed throughout shallow subtropical and tropical marine environments in the Indo-Pacific and Caribbean-Atlantic, and have traditionally been identified using pore characteristics and colony form. Until now, representatives of Millepora spp. on the island of Okinawa-jima, Japan, have been divided into five species; three branching species (Millepora intricata, M. tenera, M. dichotoma), one species with plate-like morphology (M. platyphylla), and one encrusting species (M. exaesa). There have been only a few reports from the Indo-Pacific that have studied the genetic diversity within Millepora spp., although phylogenetic analyses in the Caribbean-Atlantic have proven useful in delimiting closely-related species, while demonstrating that morphologically-based identification systems may have problems. In the present study, we sought to clarify taxonomic confusion of Millepora spp. in the Pacific by using sequence data of the ribosomal internal transcribed spacer (ITS-rDNA) of specimens from Okinawa, Japan and other localities (Johnston Atoll, Great Barrier Reef). Four separate clades were recovered from the ITS-rDNA analyses. Although we examined specimens of all three branching Millepora spp. previously reported from Okinawa-jima Island, in our phylogenetic analyses they were concentrated within a single clade, with only three specimens in other clades. Encrusting Millepora specimens were found within all clades, although it should be noted all species initially start as encrusting forms, and plate-like specimens were found within three clades. Our data also point to the existence of a previously unknown lineage within Millepora characterized by its ability to overgrow live scleractinian corals.


Asunto(s)
Biodiversidad , Evolución Molecular , Hidrozoos/genética , Filogenia , Animales , ADN Espaciador Ribosómico/análisis , Hidrozoos/clasificación , Japón , Análisis de Secuencia de ADN
19.
Dis Aquat Organ ; 131(3): 245-249, 2018 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-30459297

RESUMEN

In the summer of 2016, extensive coral bleaching occurred on the coral reefs of Okinawa, Japan, which was often lethal in shallow waters. In November 2016, after the coral bleaching event, an anomalous black band disease (ABBD) was noticed during regular monitoring of the Pachyseris-dominated upper mesophotic Ryugu Reef in Okinawa. We subsequently conducted 10 × 1 m belt transects in deeper (30-35 m depth, n = 5) and shallower areas (27-29 m, n = 7) of the reef and obtained data on coral percentage coverage, Pachyseris percentage coverage, occurrence (numbers of lesions) of ABBD, and ABBD percentage coverage on Pachyseris. Both depths showed high live coral coverage (>90%), indicating little mortality from the summer 2016 bleaching event, and Pachyseris percentage coverage was significantly higher in the deeper area (mean ± SD = 48.6 ± 45.0%) compared to the shallower area (5.1 ± 5.0%). Additionally, although numbers of ABBD occurrences (= lesions) were significantly higher in the deeper area (81.0 ± 52.8 as opposed to 8.3 ± 6.7 at shallower depths), total ABBD percentage coverage on Pachyseris was not significantly different between shallow and deep areas (7.0 ± 3.2% versus 4.7 ± 3.6%). ABBD was observed to be Pachyseris-specific at Ryugu Reef. These results indicate that similar to shallower reefs, mesophotic reefs can experience increased disease occurrences subsequent to non-lethal coral bleaching events.


Asunto(s)
Antozoos , Animales , Color , Arrecifes de Coral , Ecosistema , Japón , Estaciones del Año
20.
Mol Phylogenet Evol ; 89: 73-90, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25863336

RESUMEN

Currently the genera Parazoanthus (family Parazoanthidae) and Epizoanthus (family Epizoanthidae) are the only sponge-associated zoantharians (Cnidaria, Anthozoa). The Parazoanthidae-sponge associations are widely distributed in tropical and subtropical waters from the intertidal to the deep sea in the Atlantic and Indo-Pacific Oceans. However, the taxonomic identification of both parties is often confused due to variable morphology and wide ecological ranges. In particular, Parazoanthidae species diversity remains poorly understood in the Indo-Pacific. In the present study, the diversity of the sponge-zoanthid association in the Indo-Pacific was investigated with 71 Parazoanthidae specimens collected from 29 different locations in Japan (n=22), Australia (n=6) and Florida, USA (n=1). For all specimens morphological analyses were performed and total DNA was extracted and amplified for four DNA markers (COI-mtDNA, mt 16S-rDNA, ITS-rDNA and ALG11-nuDNA). The combined data demonstrate that the specimens of this study are clearly different from those of all described Parazoanthus species, and lead us to erect Umimayanthus gen. n., within family Parazoanthidae, containing the three newly described species U. chanpuru sp. n., U. miyabi sp. n., U. nakama sp. n. The new genus also includes the previously described species U. parasiticus (Duchassaing and Michelotti, 1860; comb. nov.), previously belonging to the genus Parazoanthus. Neighbor joining, maximum likelihood and Bayesian posterior probability phylogenetic trees clearly demonstrate the monophyly of Umimayanthus gen. n. to the exclusion of all outgroup sequences. The phylogenetic results were also compared to morphological features, and polyp sizes, amount of sand content in tissues, types of connections between polyps, and cnidae data, in particular holotrichs-1, were useful in distinguishing the different species within this new genus. This new genus can be distinguished from all other Zoantharia by a unique and conserved 9 bp insertion and a 14 bp deletion in the mt 16S-rDNA region. Additionally, compared to Parazoanthus sensu stricto (i.e. P. axinellae [Schmidt, 1862]), Umimayanthus spp. are only found associated to sponges, and have a coenenchyme much less developed than Parazoanthus sensu stricto. Each new species can be distinguished from other congeners by a unique DNA sequence, numbers of tentacle, maximum sizes of holotrichs, associated sponge morphology, and colony morphology. The identification of the host sponge species is the next logical step in this research as this may also aid in the distinction of Umimayanthus species.


Asunto(s)
Antozoos/clasificación , Antozoos/genética , Biodiversidad , Poríferos/clasificación , Poríferos/genética , Animales , Antozoos/fisiología , Australia , Secuencia de Bases , Teorema de Bayes , ADN Mitocondrial/genética , ADN Ribosómico/genética , Florida , Genes de ARNr/genética , Océano Índico , Japón , Océano Pacífico , Filogenia , Poríferos/fisiología
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