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Gert Worheide - One of the best experts on this subject based on the ideXlab platform.

  • a short lsu rrna fragment as a standard marker for integrative taxonomy in calcareous sponges porifera Calcarea
    Organisms Diversity & Evolution, 2016
    Co-Authors: Oliver Voigt, Gert Worheide
    Abstract:

    Calcareous sponges are taxonomically difficult, and their morpho-systematic classification often conflicts with molecular phylogenies. Consequently, species descriptions that rely solely on morphological characters,and taxonomic revisions appear to provide little to no information about phylogenetic affiliations and integrative approaches, combining DNA and morphological data, are applied more frequently. However, a standardized database that combines DNA sequence and morphological specimen information is still missing for calcareous sponges. The mitochondrial cytochrome oxidase subunit 1 gene (COI) is the marker of choice for rapid species identification in many other animal taxa, including demosponges, for which COI sequences and morphological information have been compiled in the sponge barcoding database (www.spongebarcoding.org). But due to the peculiarities of Calcarean mitochondrial genomes, sequencing COI in Calcarea is methodologically challenging. We here propose the use of one more commonly used DNA marker, the C-region of the 28S gene (LSU), as standard barcoding marker for Calcarea, after also considering the internal transcribed spacer (ITS) region for such proposes. Especially in the subclass Calcaronea, we observed severe problems of high intra- and intergenomic variation that impedes pan-Calcarean ITS alignments. In contrast, the C-region of LSU provides a short but phylogenetically informative DNA sequence, alignable across both subclasses with the help of a newly developed secondary structure and which also can be used to address exemplary taxonomic questions. With our work, we start to close the gap of Calcarea in the sponge barcoding project (www.spongebarcoding.org) and provide a resource for biodiversity studies and potentially for DNA-guided species identification.

  • first evaluation of mitochondrial dna as a marker for phylogeographic studies of Calcarea a case study from leucetta chagosensis
    Hydrobiologia, 2012
    Co-Authors: Oliver Voigt, Vincent Eichmann, Gert Worheide
    Abstract:

    In most animals mitochondrial DNA (mtDNA) evolves much faster than nuclear DNA. Therefore, and because of its shorter coalescent time, mitochondrial (mt) markers provide better resolution to trace more recent evolutionary events compared to nuclear DNA. But in contrast to most other Metazoa, previous studies suggested that in sponges mitochondrial sequence evolution is much slower, making mtDNA less suitable for studies at the intraspecific level. However, these observations were made in the class Demospongiae and so far no data exist for calcareous sponges (Class Calcarea). We here provide the first study that evaluates intraspecific mt sequence variation in Calcarea. We focus on arguably the best-studied species Leucetta chagosensis, for which three nuclear DNA marker datasets existed previously. We here sequenced the partial mitochondrial cytochrome oxidase subunit III gene (cox3). Our analyses reveal an unexpected variability of up to 8.5% in this mitochondrial marker. In contrast to other sponges where this marker evolves considerable slower than the nuclear internal transcribed spacer region (ITS), we found that cox3 in L. chagosensis evolves about five times as fast as ITS. The variability is similar to that of nuclear intron data of the species. The phylogeny inferred with cox3 is congruent with other markers, but separates earlier reported genetic groups much more distinctively than nuclear DNA. This provides further evidence for cryptic speciation in L. chagosensis. All these features make Calcarean mtDNA exceptional among sponges and show its suitability for phylogeographic studies and potential as a species-specific (DNA barcoding) marker to distinguish morphologically identical cryptic species.

  • molecular phylogenetic evaluation of classification and scenarios of character evolution in calcareous sponges porifera class Calcarea
    PLOS ONE, 2012
    Co-Authors: Oliver Voigt, Eilika Wulfing, Gert Worheide
    Abstract:

    Calcareous sponges (Phylum Porifera, Class Calcarea) are known to be taxonomically difficult. Previous molecular studies have revealed many discrepancies between classically recognized taxa and the observed relationships at the order, family and genus levels; these inconsistencies question underlying hypotheses regarding the evolution of certain morphological characters. Therefore, we extended the available taxa and character set by sequencing the complete small subunit (SSU) rDNA and the almost complete large subunit (LSU) rDNA of additional key species and complemented this dataset by substantially increasing the length of available LSU sequences. Phylogenetic analyses provided new hypotheses about the relationships of Calcarea and about the evolution of certain morphological characters. We tested our phylogeny against competing phylogenetic hypotheses presented by previous classification systems. Our data reject the current order-level classification by again finding non-monophyletic Leucosolenida, Clathrinida and Murrayonida. In the subclass Calcinea, we recovered a clade that includes all species with a cortex, which is largely consistent with the previously proposed order Leucettida. Other orders that had been rejected in the current system were not found, but could not be rejected in our tests either. We found several additional families and genera polyphyletic: the families Leucascidae and Leucaltidae and the genus Leucetta in Calcinea, and in Calcaronea the family Amphoriscidae and the genus Ute. Our phylogeny also provided support for the vaguely suspected close relationship of several members of Grantiidae with giantortical diactines to members of Heteropiidae. Similarly, our analyses revealed several unexpected affinities, such as a sister group relationship between Leucettusa (Leucaltidae) and Leucettidae and between Leucascandra (Jenkinidae) and Sycon carteri (Sycettidae). According to our results, the taxonomy of Calcarea is in desperate need of a thorough revision, which cannot be achieved by considering morphology alone or relying on a taxon sampling based on the current classification below the subclass level.

  • the sterols of calcareous sponges Calcarea porifera
    Chemistry and Physics of Lipids, 2008
    Co-Authors: Andrea Hagemann, Gert Worheide, Oliver Voigt, Volker Thiel
    Abstract:

    Abstract Sponges are sessile suspension-feeding organisms whose internal phylogenetic relationships are still the subject of intense debate. Sterols may have the potential to be used as independent markers to test phylogenetic hypotheses. Twenty representative specimens of calcareous sponges (class Calcarea, phylum Porifera) with a broad coverage within both subclasses Calcinea and Calcaronea were analysed for their sterol content. Two major pseudohomologous series were found, accompanied by some additional sterols. The first series encompassing conventional C27 to C29Δ5,7,22 sterols represented the major sterols, with ergosterol (ergosta-5,7,22-trien-3β-ol, C28Δ5,7,22) being most prominent in many species. The second series consisted of unusual C27 to C29Δ5,7,9(11),22 sterols. Cholesterol occurred sporadically, mostly in trace amounts. The sterol patterns did not resolve intraclass phylogenetic relationships, namely the distinction between the subclasses, Calcinea and Calcaronea. This pointed towards major Calcarean lipid traits being established prior to the separation of subclasses. Furthermore, Calcarean sterol patterns clearly differ from those found in Hexactinellida, whereas partial overlap occurred with some Demospongiae. Hence, sterols only partly reflect the phylogenetic separation of Calcarea from both of the other poriferan classes that was proposed by recent molecular work and fatty acid analyses.

  • The sterols of calcareous sponges (Calcarea, Porifera).
    Chemistry and physics of lipids, 2008
    Co-Authors: Andrea Hagemann, Gert Worheide, Oliver Voigt, Volker Thiel
    Abstract:

    Sponges are sessile suspension-feeding organisms whose internal phylogenetic relationships are still the subject of intense debate. Sterols may have the potential to be used as independent markers to test phylogenetic hypotheses. Twenty representative specimens of calcareous sponges (class Calcarea, phylum Porifera) with a broad coverage within both subclasses Calcinea and Calcaronea were analysed for their sterol content. Two major pseudohomologous series were found, accompanied by some additional sterols. The first series encompassing conventional C(27) to C(29)Delta(5,7,22) sterols represented the major sterols, with ergosterol (ergosta-5,7,22-trien-3beta-ol, C(28)Delta(5,7,22)) being most prominent in many species. The second series consisted of unusual C(27) to C(29)Delta(5,7,9(11),22) sterols. Cholesterol occurred sporadically, mostly in trace amounts. The sterol patterns did not resolve intraclass phylogenetic relationships, namely the distinction between the subclasses, Calcinea and Calcaronea. This pointed towards major Calcarean lipid traits being established prior to the separation of subclasses. Furthermore, Calcarean sterol patterns clearly differ from those found in Hexactinellida, whereas partial overlap occurred with some Demospongiae. Hence, sterols only partly reflect the phylogenetic separation of Calcarea from both of the other poriferan classes that was proposed by recent molecular work and fatty acid analyses.

Michelle Klautau - One of the best experts on this subject based on the ideXlab platform.

  • the new sponge species amphoriscus pedunculatus porifera Calcarea
    Zootaxa, 2017
    Co-Authors: Michelle Klautau, Fernanda F Cavalcanti, Radovan Borojevic
    Abstract:

    Amphoriscus is a widespread genus with 17 species. A new species was found in SE Brazil and it represents the second species of this genus in Brazilian waters. Amphoriscus pedunculatus sp. nov. has a special structure, a peduncle, to attach to the substrate. Special attachment structures are not very common in the class Calcarea but this is the third species of the genus with a peduncle. Besides peduncle, another attachment structure found in some species of Amphoriscus is the root-tuft, an attachment structure composed of diactines and anchor-like triactines or tetractines. The evolution of these attachment structures in Amphoriscus is not known but they have also been found out of this genus, suggesting that these structures appeared several times during the evolution of Calcarea or that species currently classified in different genera are in fact congeneric.

  • new leucettidae de laubenfels 1936 porifera Calcarea from western australia
    Zootaxa, 2016
    Co-Authors: Pedro Leocorny, Aline Alencar, Jane Fromont, Michelle Klautau
    Abstract:

    This paper reports four new Leucettidae (Porifera, Calcarea) from Western Australia, with two representatives of Leucetta and two of Pericharax : L. foliata sp. nov., L . purpurea sp. nov., Pericharax crypta sp. nov., and P. vallii sp. nov. This is the first time tripods have been described within Pericharax . In addition, one species ( L . foliata sp. nov.) has an external morphology not previously reported for Leucetta , and for the first time tetractines of the inhalant and exhalant canals have been distinguished. Leucettidae now comprises 28 species, eight of them occur in Western Australia, which means this Australian State has the highest species richness for this family in Australia. The WA coastline has been largely unexplored for Calcarea so it is likely that further collecting will yield additional species. Leucetta microraphis is the most widespread species of Leucettidae in Australia, occurring in all States except the Northern Territory and Tasmania. We highlight the importance of a revision of the Leucettidae using molecular and morphological characters to determine which morphological characters have a phylogenetic signal.

  • fragmentation fusion and genetic homogeneity in a calcareous sponge porifera Calcarea
    Journal of Experimental Zoology, 2016
    Co-Authors: Andre Padua, Pedro Leocorny, Marcio R Custodio, Michelle Klautau
    Abstract:

    Sessile marine invertebrates living on hard substrata usually present strategies such as size variations, longer life spans, fragmentation and fusion to occupy and compete for space. Calcareous sponges are usually small and short-lived, and some species are known to undergo frequent fragmentation and fusion events. However, whether fusion occurs only between genetically identical individuals remains unclear. We investigated the occurrence of chimaeras in the calcareous sponge Clathrina aurea by following the dynamics of fragmentation and fusion of 66 individuals in the field for up to 18 months and determined size variations and the life span of each individual. Microsatellites were used to determine whether fusion events occur among genetically different individuals. Growth and shrinkage of individuals were frequently observed, showing that size cannot be associated with age in C. aurea. The life span of the species ranged from 1 to 16 months (mean: 4.7 months). Short life spans and variable growth rates have been observed in other species of the class Calcarea. Fragmentation and fusion events were observed, but fusion events always occurred between genetically identical individuals, as has been suggested by graft experiments in adult Demospongiae and other Calcarea. These results suggest that at least C. aurea adults may have some mechanism to avoid chimaerism.

  • adriatic Calcarean sponges porifera Calcarea with the description of six new species and a richness analysis
    European journal of taxonomy, 2016
    Co-Authors: Michelle Klautau, Mirna Imesek, Fernanda Azevedo, Bruna Plese, Vedran Nikolic, Helena Cetkovic
    Abstract:

    In this study we analyze the Calcarean sponge diversity of the Adriatic Sea, the type locality of some of the first described species of Calcarean sponges. Morphological and molecular approaches are combined for the taxonomic identification. Our results reveal six species new to science and provisionally endemic to the Adriatic Sea ( Ascandra spalatensis sp. nov., Borojevia croatica sp. nov., Leucandra falakra sp. nov., L. spinifera sp. nov., Paraleucilla dalmatica sp. nov., and Sycon ancora sp. nov.), one species previously known only from the Southwestern Atlantic ( Clathrina conifera ), and three already known from the Adriatic Sea ( Ascaltis reticulum , Borojevia cerebrum , and Clathrina primordialis ). We confirm the presence of the alien species Paraleucilla magna in the Adriatic and again record Clathrina blanca , C. clathrus , and C. rubra . We emend the description of the genus Ascaltis , propose a lectotype for Borojevia cerebrum and synonymise B. decipiens with B. cerebrum . A checklist of all Calcarean species previously and currently known from the Adriatic Sea (39 species) is given. The Central Adriatic is indicated as the richest Calcarean sponge fauna sector; however, the biodiversity of this class is underestimated in the whole Adriatic Sea and new systematic surveys are desirable.

  • population dynamics of cryptogenic Calcarean sponges porifera Calcarea in southeastern brazil
    Marine Ecology, 2013
    Co-Authors: Fernanda F Cavalcanti, Luis Felipe Skinner, Michelle Klautau
    Abstract:

    The Calcarean sponge Paraleucilla magna is classified as being an invasive species on the Mediterranean Sea, where it causes economic damages to mollusc farms. On the Brazilian coast, this species is considered to be cryptogenic, and information on its ecology is scarce. The same is true for Sycettusa hastifera, another Calcarean sponge with a worldwide distribution. Data on the ecology of these species could help in elucidating their potential to become a threat if they are found to be exotic species in Brazil. In the present work, we studied habitat selection, growth and mortality of early juveniles of P. magna and habitat selection of S. hastifera in a Marine Reserve from Southeastern Brazil, where these species are abundant in the benthic community. Granite plates were used for habitat selection analysis, varying in substrate inclination (vertical and horizontal) and exposure to light and hydrodynamism (exposed and sheltered). To analyse the growth and mortality rates, sponges were mapped and then measured once a week for 10 weeks. If a monitored sponge was not found in the following week, it was considered to be dead. Our results showed that, although P. magna and S. hastifera are capable of inhabiting substrates exposed to different environmental conditions, they showed habitat preferences. Growth of the juveniles of P. magna seemed not to have damaged any neighbouring invertebrates. The mortality of juveniles of this species was higher during the first 2 weeks of life but its causes could not be elucidated.

Oliver Voigt - One of the best experts on this subject based on the ideXlab platform.

  • a short lsu rrna fragment as a standard marker for integrative taxonomy in calcareous sponges porifera Calcarea
    Organisms Diversity & Evolution, 2016
    Co-Authors: Oliver Voigt, Gert Worheide
    Abstract:

    Calcareous sponges are taxonomically difficult, and their morpho-systematic classification often conflicts with molecular phylogenies. Consequently, species descriptions that rely solely on morphological characters,and taxonomic revisions appear to provide little to no information about phylogenetic affiliations and integrative approaches, combining DNA and morphological data, are applied more frequently. However, a standardized database that combines DNA sequence and morphological specimen information is still missing for calcareous sponges. The mitochondrial cytochrome oxidase subunit 1 gene (COI) is the marker of choice for rapid species identification in many other animal taxa, including demosponges, for which COI sequences and morphological information have been compiled in the sponge barcoding database (www.spongebarcoding.org). But due to the peculiarities of Calcarean mitochondrial genomes, sequencing COI in Calcarea is methodologically challenging. We here propose the use of one more commonly used DNA marker, the C-region of the 28S gene (LSU), as standard barcoding marker for Calcarea, after also considering the internal transcribed spacer (ITS) region for such proposes. Especially in the subclass Calcaronea, we observed severe problems of high intra- and intergenomic variation that impedes pan-Calcarean ITS alignments. In contrast, the C-region of LSU provides a short but phylogenetically informative DNA sequence, alignable across both subclasses with the help of a newly developed secondary structure and which also can be used to address exemplary taxonomic questions. With our work, we start to close the gap of Calcarea in the sponge barcoding project (www.spongebarcoding.org) and provide a resource for biodiversity studies and potentially for DNA-guided species identification.

  • first evaluation of mitochondrial dna as a marker for phylogeographic studies of Calcarea a case study from leucetta chagosensis
    Hydrobiologia, 2012
    Co-Authors: Oliver Voigt, Vincent Eichmann, Gert Worheide
    Abstract:

    In most animals mitochondrial DNA (mtDNA) evolves much faster than nuclear DNA. Therefore, and because of its shorter coalescent time, mitochondrial (mt) markers provide better resolution to trace more recent evolutionary events compared to nuclear DNA. But in contrast to most other Metazoa, previous studies suggested that in sponges mitochondrial sequence evolution is much slower, making mtDNA less suitable for studies at the intraspecific level. However, these observations were made in the class Demospongiae and so far no data exist for calcareous sponges (Class Calcarea). We here provide the first study that evaluates intraspecific mt sequence variation in Calcarea. We focus on arguably the best-studied species Leucetta chagosensis, for which three nuclear DNA marker datasets existed previously. We here sequenced the partial mitochondrial cytochrome oxidase subunit III gene (cox3). Our analyses reveal an unexpected variability of up to 8.5% in this mitochondrial marker. In contrast to other sponges where this marker evolves considerable slower than the nuclear internal transcribed spacer region (ITS), we found that cox3 in L. chagosensis evolves about five times as fast as ITS. The variability is similar to that of nuclear intron data of the species. The phylogeny inferred with cox3 is congruent with other markers, but separates earlier reported genetic groups much more distinctively than nuclear DNA. This provides further evidence for cryptic speciation in L. chagosensis. All these features make Calcarean mtDNA exceptional among sponges and show its suitability for phylogeographic studies and potential as a species-specific (DNA barcoding) marker to distinguish morphologically identical cryptic species.

  • molecular phylogenetic evaluation of classification and scenarios of character evolution in calcareous sponges porifera class Calcarea
    PLOS ONE, 2012
    Co-Authors: Oliver Voigt, Eilika Wulfing, Gert Worheide
    Abstract:

    Calcareous sponges (Phylum Porifera, Class Calcarea) are known to be taxonomically difficult. Previous molecular studies have revealed many discrepancies between classically recognized taxa and the observed relationships at the order, family and genus levels; these inconsistencies question underlying hypotheses regarding the evolution of certain morphological characters. Therefore, we extended the available taxa and character set by sequencing the complete small subunit (SSU) rDNA and the almost complete large subunit (LSU) rDNA of additional key species and complemented this dataset by substantially increasing the length of available LSU sequences. Phylogenetic analyses provided new hypotheses about the relationships of Calcarea and about the evolution of certain morphological characters. We tested our phylogeny against competing phylogenetic hypotheses presented by previous classification systems. Our data reject the current order-level classification by again finding non-monophyletic Leucosolenida, Clathrinida and Murrayonida. In the subclass Calcinea, we recovered a clade that includes all species with a cortex, which is largely consistent with the previously proposed order Leucettida. Other orders that had been rejected in the current system were not found, but could not be rejected in our tests either. We found several additional families and genera polyphyletic: the families Leucascidae and Leucaltidae and the genus Leucetta in Calcinea, and in Calcaronea the family Amphoriscidae and the genus Ute. Our phylogeny also provided support for the vaguely suspected close relationship of several members of Grantiidae with giantortical diactines to members of Heteropiidae. Similarly, our analyses revealed several unexpected affinities, such as a sister group relationship between Leucettusa (Leucaltidae) and Leucettidae and between Leucascandra (Jenkinidae) and Sycon carteri (Sycettidae). According to our results, the taxonomy of Calcarea is in desperate need of a thorough revision, which cannot be achieved by considering morphology alone or relying on a taxon sampling based on the current classification below the subclass level.

  • the sterols of calcareous sponges Calcarea porifera
    Chemistry and Physics of Lipids, 2008
    Co-Authors: Andrea Hagemann, Gert Worheide, Oliver Voigt, Volker Thiel
    Abstract:

    Abstract Sponges are sessile suspension-feeding organisms whose internal phylogenetic relationships are still the subject of intense debate. Sterols may have the potential to be used as independent markers to test phylogenetic hypotheses. Twenty representative specimens of calcareous sponges (class Calcarea, phylum Porifera) with a broad coverage within both subclasses Calcinea and Calcaronea were analysed for their sterol content. Two major pseudohomologous series were found, accompanied by some additional sterols. The first series encompassing conventional C27 to C29Δ5,7,22 sterols represented the major sterols, with ergosterol (ergosta-5,7,22-trien-3β-ol, C28Δ5,7,22) being most prominent in many species. The second series consisted of unusual C27 to C29Δ5,7,9(11),22 sterols. Cholesterol occurred sporadically, mostly in trace amounts. The sterol patterns did not resolve intraclass phylogenetic relationships, namely the distinction between the subclasses, Calcinea and Calcaronea. This pointed towards major Calcarean lipid traits being established prior to the separation of subclasses. Furthermore, Calcarean sterol patterns clearly differ from those found in Hexactinellida, whereas partial overlap occurred with some Demospongiae. Hence, sterols only partly reflect the phylogenetic separation of Calcarea from both of the other poriferan classes that was proposed by recent molecular work and fatty acid analyses.

  • The sterols of calcareous sponges (Calcarea, Porifera).
    Chemistry and physics of lipids, 2008
    Co-Authors: Andrea Hagemann, Gert Worheide, Oliver Voigt, Volker Thiel
    Abstract:

    Sponges are sessile suspension-feeding organisms whose internal phylogenetic relationships are still the subject of intense debate. Sterols may have the potential to be used as independent markers to test phylogenetic hypotheses. Twenty representative specimens of calcareous sponges (class Calcarea, phylum Porifera) with a broad coverage within both subclasses Calcinea and Calcaronea were analysed for their sterol content. Two major pseudohomologous series were found, accompanied by some additional sterols. The first series encompassing conventional C(27) to C(29)Delta(5,7,22) sterols represented the major sterols, with ergosterol (ergosta-5,7,22-trien-3beta-ol, C(28)Delta(5,7,22)) being most prominent in many species. The second series consisted of unusual C(27) to C(29)Delta(5,7,9(11),22) sterols. Cholesterol occurred sporadically, mostly in trace amounts. The sterol patterns did not resolve intraclass phylogenetic relationships, namely the distinction between the subclasses, Calcinea and Calcaronea. This pointed towards major Calcarean lipid traits being established prior to the separation of subclasses. Furthermore, Calcarean sterol patterns clearly differ from those found in Hexactinellida, whereas partial overlap occurred with some Demospongiae. Hence, sterols only partly reflect the phylogenetic separation of Calcarea from both of the other poriferan classes that was proposed by recent molecular work and fatty acid analyses.

Volker Thiel - One of the best experts on this subject based on the ideXlab platform.

  • the sterols of calcareous sponges Calcarea porifera
    Chemistry and Physics of Lipids, 2008
    Co-Authors: Andrea Hagemann, Gert Worheide, Oliver Voigt, Volker Thiel
    Abstract:

    Abstract Sponges are sessile suspension-feeding organisms whose internal phylogenetic relationships are still the subject of intense debate. Sterols may have the potential to be used as independent markers to test phylogenetic hypotheses. Twenty representative specimens of calcareous sponges (class Calcarea, phylum Porifera) with a broad coverage within both subclasses Calcinea and Calcaronea were analysed for their sterol content. Two major pseudohomologous series were found, accompanied by some additional sterols. The first series encompassing conventional C27 to C29Δ5,7,22 sterols represented the major sterols, with ergosterol (ergosta-5,7,22-trien-3β-ol, C28Δ5,7,22) being most prominent in many species. The second series consisted of unusual C27 to C29Δ5,7,9(11),22 sterols. Cholesterol occurred sporadically, mostly in trace amounts. The sterol patterns did not resolve intraclass phylogenetic relationships, namely the distinction between the subclasses, Calcinea and Calcaronea. This pointed towards major Calcarean lipid traits being established prior to the separation of subclasses. Furthermore, Calcarean sterol patterns clearly differ from those found in Hexactinellida, whereas partial overlap occurred with some Demospongiae. Hence, sterols only partly reflect the phylogenetic separation of Calcarea from both of the other poriferan classes that was proposed by recent molecular work and fatty acid analyses.

  • The sterols of calcareous sponges (Calcarea, Porifera).
    Chemistry and physics of lipids, 2008
    Co-Authors: Andrea Hagemann, Gert Worheide, Oliver Voigt, Volker Thiel
    Abstract:

    Sponges are sessile suspension-feeding organisms whose internal phylogenetic relationships are still the subject of intense debate. Sterols may have the potential to be used as independent markers to test phylogenetic hypotheses. Twenty representative specimens of calcareous sponges (class Calcarea, phylum Porifera) with a broad coverage within both subclasses Calcinea and Calcaronea were analysed for their sterol content. Two major pseudohomologous series were found, accompanied by some additional sterols. The first series encompassing conventional C(27) to C(29)Delta(5,7,22) sterols represented the major sterols, with ergosterol (ergosta-5,7,22-trien-3beta-ol, C(28)Delta(5,7,22)) being most prominent in many species. The second series consisted of unusual C(27) to C(29)Delta(5,7,9(11),22) sterols. Cholesterol occurred sporadically, mostly in trace amounts. The sterol patterns did not resolve intraclass phylogenetic relationships, namely the distinction between the subclasses, Calcinea and Calcaronea. This pointed towards major Calcarean lipid traits being established prior to the separation of subclasses. Furthermore, Calcarean sterol patterns clearly differ from those found in Hexactinellida, whereas partial overlap occurred with some Demospongiae. Hence, sterols only partly reflect the phylogenetic separation of Calcarea from both of the other poriferan classes that was proposed by recent molecular work and fatty acid analyses.

  • the fatty acids of calcareous sponges Calcarea porifera
    Chemistry and Physics of Lipids, 2006
    Co-Authors: Andrea Schreiber, Gert Worheide, Volker Thiel
    Abstract:

    Twenty-nine specimens of calcareous sponges (Class Calcarea, Phylum Porifera), covering thirteen representative species of the families Soleneiscidae, Leucaltidae, Levinellidae, Leucettidae, Clathrinidae, Sycettidae, Grantiidae, Jenkinidae, and Heteropiidae were analysed for their fatty acids. The fatty acids of Calcarea generally comprise saturated and monounsaturated linear ( n -), and terminally methylated ( iso- , anteiso- ) C 14 –C 20 homologues. Furthermore, polyunsaturated C 22 fatty acids and the isoprenoic 4,8,12-trimethyltridecanoic acid were found. The most prominent compounds are n -C 16 , iso -C 17 , iso -C 18 , n -C 18 , n -C 20 . In addition, a high abundance of the exotic 16-methyloctadecanoic acid ( anteiso -C 19 ) appears to be a characteristic trait of Calcarea. Long-chain ‘demospongic acids’, typically found in Demospongiae and Hexactinellida, are absent in Calcarea. The completely different strategy of Calcarean fatty acid synthesis supports their phylogenetic distinctiveness from a common Demospongiae/Hexactinellida taxon. Both intraspecific and intraclass patterns of Calcarea showed great similarity, suggesting a conserved fatty acid composition that already existed in the last common ancestor of Calcinea and Calcaronea, i.e. before subclasses diverged.

J Gartner - One of the best experts on this subject based on the ideXlab platform.

  • tendinosis Calcarea behandlungsergebnisse mit dem needling
    Zeitschrift Fur Orthopadie Und Ihre Grenzgebiete, 2008
    Co-Authors: J Gartner
    Abstract:

    : In a prospective study, 33 patients with calcifying tendinitis had a needling in local anaesthesia performed under control of an image converter. There was at least a one year follow-up period. Resorption of the hydroxyapatite deposits was seen in 23 instances; 75% of all patients were free of symptoms or had considerably improved (Table 3). For better assessment of these results we embarked on an additional retrospective study observing the spontaneous evolution of 235 hydroxyapatite deposits for 3 years on average. On the x-ray, these deposits had a characteristic appearance and could be classified into one of three types: either sharply outlined and densely structured (type I), or with cloudy limitations and transparent in structure (type III). In addition we saw deposits combining the features of both of the above named types (type II) (Table 5, Fig. 6). Based on this classification, a clear correlation was revealed to exist between initial x-ray findings and the frequency of resorption after needling: with type I, complete resorption was seen in 33% of the cases, with type II in 71%, and with type III in 85% of the cases (Table 6). With type II, however, only half of the patients were free of symptoms. Surgical removal of the hydroxyapatite deposits became necessary in 3 patients because of persisting heavy pains. As complication we observed intraoperatively an incomplete tear of the rotator cuff, the relation of which to the needling remained unsure. In this context, the question is discussed whether calcifying tendinitis and rupture of the rotator cuff may represent two disease entities of identical origin.(ABSTRACT TRUNCATED AT 250 WORDS)

  • tendinosis Calcarea der schulter
    Orthopade, 1995
    Co-Authors: J Gartner, A Heyer
    Abstract:

    : Degenerative ossification is formed directly at the major tubercle. Like in any other gliding tendon, fibrocartilage cells lie on the articular side of the rotator tendon at the pivot of the humerus head. Typically, the calcific deposits of calcifying tendinitis are found between these two areas. At this site, hydroxyapatite is usually formed by fibrocartilage cells through an unknown stimulus. There is no ossification. This is a two-phase disease. During the chronic initial phase, a calcific deposit is formed in the tendon of the rotator cuff. In the X-ray, it is clearly circumscribed and has a dense appearance (type I). Pain is inconsistent and may exist for years. In the acute phase, the deposit undergoes spontaneous resolution. Now it takes on a translucent and cloudy appearance without clear circumscription (type III). Patients experience severe pain for 2-3 weeks. Finally, a normally functioning shoulder joint will result. The X-ray therefore allows a prognostic conclusion. In a study including 235 calcific deposits, it became clear that there are some cases where it is not possible to designate the specific X-ray morphology to a given deposit (type II). Irrespective of the phase of disease, the so-called calcific deposit is composed of poorly mineralized hydroxyapatite. For a diagnosis, we require: a typical history, clinical findings consistent with tendinitis of the rotator cuff, calcific deposits in the tendon associated with signs and symptoms of tendinitis. It is recommended that radiographs be taken at least in AP projections with the shoulder in internal and external rotation to demonstrate the deposits without super-imposition. Ultrasound shows concomitant bursitis and is useful for the differential diagnosis of rupture of the rotator cuff. Radiographic diagnosis is most difficult when there are small opacifications near the rotator attachment. In this case, allocation may become possible only later in the course of disease. Initial treatment should always be non-operative. Almost all therapeutic modalities are said to be quite successful. Needles under local anesthesia is recommended only for patients with marked pain who lack any signs of resolution in the X-ray. According to a prospective study, the success rates of needles depend on the roentgenologic findings: in type I deposits, resolution occurs in 33%, in typq II deposits in 71%. Freedom from pain is seen in about 50% of the patients. Type III deposits undergo resolution with and without therapy in about 2-3 weeks. Post-operative results are reported to lie between 77% and 96% irrespective of the method used.(ABSTRACT TRUNCATED AT 400 WORDS)

  • Das Needling bei Tendinosis Calcarea der Rotatorenmanschette
    Operative Orthopädie und Traumatologie, 1993
    Co-Authors: J Gartner
    Abstract:

    Perkutane Stichelung und Ausspülung eines sogenannten Kalkdepots (Hydroxylapatitdepot) unter Durchleuchtungskontrolle.