235 research outputs found

    Molecular Phylogenetic Evidence Supports a New Family of Octocorals and a New Genus of Alcyoniidae (Octocorallia: Alcyonacea)

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    Molecular phylogenetic evidence indicates that the octocoral family Alcyoniidae is highly polyphyletic, with genera distributed across Octocorallia in more than 10 separate clades. Most alcyoniid taxa belong to the large and poorly resolved Holaxonia–Alcyoniina clade of octocorals, but members of at least four genera of Alcyoniidae fall outside of that group. As a first step towards revision of the family, we describe a new genus, Parasphaerasclera gen. n., and family, Parasphaerascleridae fam. n., of Alcyonacea to accommodate species of Eleutherobia Pütter, 1900 and Alcyonium Linnaeus, 1758 that have digitiform to digitate or lobate growth forms, completely lack sclerites in the polyps, and have radiates or spheroidal sclerites in the colony surface and interior. Parasphaerascleridae fam. n. constitutes a well-supported clade that is phylogenetically distinct from all other octocoral taxa. We also describe a new genus of Alcyoniidae, Sphaerasclera gen. n., for a species of Eleutherobia with a unique capitate growth form. Sphaerasclera gen. n. is a member of the Anthomastus–Corallium clade of octocorals, but is morphologically and genetically distinct from Anthomastus Verrill, 1878 and Paraminabea Williams & Alderslade, 1999, two similar but dimorphic genera of Alcyoniidae that are its sister taxa. In addition, we have re-assigned two species of Eleutherobia that have clavate to capitate growth forms, polyp sclerites arranged to form a collaret and points, and spindles in the colony interior to Alcyonium, a move that is supported by both morphological and molecular phylogenetic evidenc

    Sinularia Leptoclados (Ehrenberg, 1834) (Cnidaria: Octocorallia) Re-Examined

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    Sinularia leptoclados (Ehrenberg, 1834) is re-described. Sinularia leptoclados var. gonatodes Kolonko, 1926 is synonymized with S. maxima Verseveldt, 1977. Two new species of Sinularia with digitiform lobules, leptoclados-type surface clubs and unbranched interior spindles, are described. An updated maximum likelihood tree of Sinularia species with leptoclados-type clubs (clade 5C) based on two mitochondrial genes (mtMutS, COI) and a nuclear gene (28S rDNA) is presented

    Revisionary systematics of Octocorallia (Cnidaria: Anthozoa) guided by phylogenomics

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    The anthozoan sub-class Octocorallia includes over 3500 nominal species of soft corals and gorgonian sea fans, many of which serve as critical foundation species in benthic marine ecosystems in shallow waters to the deep sea. Despite their familiarity and ecological impor-tance, the diversity and taxonomy of octocorals remain poorly known. All of the orders, subordinal groups, and a majority of families have been recognized to be poly- or paraphyletic, but poor resolution of the deeper nodes in mitochondrial or single-locus nuclear gene trees have hindered formal revision of the higher-level taxonomy of the group. We used sequence data from target-capture of 739 ultraconserved and exon loci to reconstruct a fully resolved phylogeny for 185 octocoral taxa represent-ing 55 of 63 currently recognized families. We use this phylogeny, sup-plemented with a gene tree for mitochondrial mtMutS for an additional 107 taxa, to guide a revision of the families and orders of Octocorallia. We (1) elevate the anthozoan sub-classes Octocorallia and Hexacorallia to the rank of Class; (2) replace the three currently recognized orders of Octocorallia (Alcyonacea, Pennatulacea, Helioporacea) with two new orders reflecting reciprocally monophyletic major clades; and (3) revise all families with the exception of the 15 recognized families of sea pens, which we accommodate within a new superfamily. The revised classifi-cation of Octocorallia thus comprises 79 families, including 18 that are newly described and three that have been reinstated or elevated in rank. In addition, two new genera are described and another three reinstated. We leave the family assignment of 46 of 413 genera as incertae sedis until further molecular or morphological data can be obtained to confirm their phylogenetic affinities

    Anémonas anillo, una visión general (Cnidaria, Anthozoa, Actiniaria)

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    The present observations represent a new record of species of Actiniaria that are able to attach to a gorgonian branch by surrounding it with a solid piece of tissue junction and a significant reduction of the coelenteron. Ring sea anemones are provisionally placed in the Actinostolidae. They seem to be more common at depths between 85 and 1500 m., and according to our observations they are specialized to exclusively colonize on some species of gorgonians or pennatulaceans. Parasitism best describes the relationship between ring sea anemones and their hosts. We recognize five different species of ring sea anemones, one described by Hiles (1899) as Peronanthus verrucellae, and the others named by us provisionally as Peronanthus sp1, sp2, sp3 & sp4. The strategy displayed by ring sea anemones has several advantages, such as placement economy (see above), a better attachment against any current action, exploitation of food resources inaccessible to most other Actiniarians, and it allows them avoidance of habitat competition. The impossibility to colonize any other substrate but a certain group of gorgonians and a reduction of the gastric cavity are the main disadvantages detected in the ring sea anemones’ way of life. Apparently, this group of sea anemones is widespread through the Pacific Ocean.Un nuevo grupo de especies de actiniarios que desarrollan un nuevo sistema para afianzarse alrededor de los ejes de gorgonias y pennatuláceos es estudiado por nosotros en el presente trabajo. Se trata de un anillo de tejido que rodea los ejes y queda perfectamente sellado por medio de uniones del tejido produciendo una reducción del celenterón. Anémonas anillo es como las hemos denominado y provisionalmente han sido incluidas dentro de la familia Actinostolidae. Parece que son comunes en profundidades comprendidas entre los 85 y los 1500 metros, colonizando solamente determinadas especies de gorgonias y de pennatuláceos. El parasitismo es la relación que mejor describe lo que acontece entre las anémonas y los octocorales que la portan. Hay, al menos, cinco especies diferentes de anémonas anillo, la primera fue descrita por Hiles (1899) como Peronanthus verrucellae, las otras especies las denominamos provisionalmente como Peronanthus sp1, sp2, sp3 y sp4. El modo de vida de estas especies presenta ciertas ventajas como son: una reducción del espacio para asentarse, una mejor fijación frente a fenómenos de corriente, la capacidad para explotar recursos inaccesibles a la mayoría de los actiniarios y por último la falta de competencia con otras especies por el hábitat. La imposibilidad de colonizar otros sustratos y la reducción de la cavidad gástrica son las principales desventajas que presenta este modo de vida exhibido por las anémonas anillo. Aparentemente este grupo de anémonas está ampliamente distribuido en el Indo-Pacífico

    The Effect of Credit Derivatives on Financial Stability

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    Due to the recent financial turmoil, questions have been raised about the impact ofcomplex financial products, like credit derivatives, on financial stability. The academicliterature however does not provide a clear answer to this question. This paper empiricallylinks the stability of the financial sector to the use of credit derivatives for the main constituentsof the European financial sector. We find that the use of credit derivatives increases theprobability of default and thus reduces the overall financial sector stability. In addition,we find evidence that this relationship is progressive and economically meaningful

    Lobophytones O–T, New Biscembranoids and Cembranoid from Soft Coral Lobophytum pauciflorum

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    Chemical examination of a Chinese soft coral Lobophytum pauciflorum resulted in the isolation of five new biscembranoids named lobophytones O–S (1–5) and a new “monomeric” cembrane lobophytone T (6). The structures of the new compounds were elucidated by interpretation of 1D and 2D NMR (COSY, HSQC, HMBC, and NOESY) spectroscopic data in association with MS and IR data. Lobophytone Q showed significant inhibition against lipopolysaccharide (LPS)-induced nitric oxide (NO) release in mouse peritoneal macrophages, while lobophytones Q and T showed inhibitory activities against the bacteria S. aureus and S. pneumoniae

    New Records of the Cryptogenic Soft Coral Genus Stragulum (Tubiporidae) from the Eastern Caribbean and the Persian Gulf

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    The monotypic soft coral genus Stragulum van Ofwegen and Haddad, 2011 (Octocorallia: Malacalcyonacea: Tubiporidae) was originally described from Brazil, southwest Atlantic Ocean. Here, we report the first records of the genus from the eastern Caribbean and the Persian Gulf in the northwest Indian Ocean. We compare the morphological features of specimens, together with molecular data from three commonly used barcoding markers (COI, mtMutS, 28S rDNA) and 308 ultraconserved elements (UCE) and exon loci sequenced using a target-enrichment approach. The molecular and morphological data together suggest that specimens from all three localities are the same species, i.e., Stragulum bicolor van Ofwegen and Haddad, 2011. It is still not possible to establish the native range of the species or determine whether it may be an introduced species due to the limited number of specimens included in this study. However, the lack of historical records, its fouling abilities on artificial substrates, and a growing number of observations support the invasive nature of the species in Brazilian and Caribbean waters and therefore suggest that it may have been introduced into the Atlantic from elsewhere. Interestingly, the species has not shown any invasive behaviour in the Persian Gulf, where it has been found only on natural, rocky substrates. The aim of the present report is to create awareness of this taxon with the hope that this will lead to new records from other localities and help to establish its native range

    Non-native coral species dominate the fouling community on a semi-submersible platform in the southern Caribbean

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    A coral community was examined on a semi-submersible platform that was moored at the leeward side of Curaçao, in the southern Caribbean, from August 2016 until August 2017. This community included several non-native or cryptogenic species. Among them were two scleractinian corals (Tubastraea coccinea and T. tagusensis) and two octocorals (Chromonephthea sp. and an unidentified Nephtheidae sp.). This is the first reported presence of T. tagusensis in the southern Caribbean, and the genus Chromonephthea in the Caribbean region. An ascidian, Perophora cf. regina, is also reported from the southern Caribbean for the first time, as well as a coral-associated vermetid gastropod, Petaloconchus sp., first recorded in the Caribbean in 2014. Lack of biofouling management could potentially harm indigenous marine fauna through the introduction of non-native species. Therefore monitoring communities associated with semi-submersible platforms is essential to track the presence and dispersal of non-native, potentially invasive species
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