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John N. A. Hooper - One of the best experts on this subject based on the ideXlab platform.
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The systematics of Raspailiidae (Demospongiae: Poecilosclerida: Microcionina) re-analysed with a ribosomal marker
Journal of the Marine Biological Association of the United Kingdom, 2007Co-Authors: Dirk Erpenbeck, Sue E. List-armitage, Bernard M. Degnan, Gert Wörheide, Belinda Alvarez, John N. A. HooperAbstract:We present a 28S rDNA gene tree of selected Raspailiidae, Axinellidae and other demosponges to obtain insight into raspailiid phylogeny and character evolution. The Raspailiidae in our data set cluster in a well-supported clade, distinguished from Axinellidae, Agelasida and Hadromerida. Raspailia (s.s.), Eurypon, Sollasella, Aulospongus and Ectyoplasia form a Raspailiidae clade. Some Raspailia subgenera, in particular R. (Parasyringella), are not retrieved monophyletically. Trikentrion falls into the Thrinacophorinae, and not the Cyamoninae as earlier hypothesized. The axinellid genera Ptilocaulis and Reniochalina also cluster with Raspailiidae, distant from the other Axinellidae. The suitability of particular morphological characters for raspailiid phylogeny is discussed.
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Affinities of the family Sollasellidae (Porifera, Demospongiae). II. Molecular evidence
Contributions to Zoology, 2007Co-Authors: Dirk Erpenbeck, John N. A. Hooper, Sue E. List-armitage, Bernard M. Degnan, Gert Wörheide, Rob W. M. Van SoestAbstract:This is the second part of a revision and re-classification of the demosponge family Sollasellidae, and an example of a successful use of combined morphological and molecular data. Sollasella had been a poorly known, long forgotten taxon, placed incertae sedis in the order Hadromerida in the last major revision of the demosponges. It has recently been suggested to belong to Raspailiidae in the order Poecilosclerida due to striking morphological similarities. The present analysis verified this re-classification using molecular markers. Comparing 28S rDNA fragments of Sollasella cervicornis, a newly described species S. moretonensis and a representative set of raspailiid and hadromerid samples. In our analyses Sollasella clearly clusters inside the Raspailiidae clade, and distantly from hadromerid taxa. Supporting morphological hypothesis of Van Soest et al. (2006), that Sollasella is a raspailiid sponge.
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Order Hadromerida Topsent, 1894
Systema Porifera, 2002Co-Authors: John N. A. Hooper, Rob W. M. Van SoestAbstract:Hadromerida Topsent (Demospongiae), including Clavulina Vosmaer and Astromonaxonellida Dendy, contains 23 nominal families or subfamilies of which 13 families are recognised here (two allocated as incertae sedis). The order includes sponges with monaxonic megascleres (tylostyles, subtylostyles, oxeas or derivatives) producing radiate or subradiate skeletal arrangement, although this arrangement may be obvious only in the peripheral skeleton in some, often with scarce spongin and consequently firm, non-elastic consistency. Ectosomal spicules are often smaller than choanosomal ones, and where present these may form a prominent cortical skeleton. Microscleres may include various forms of euasters, spirasters, rhabds, microxeas and/or raphides, although many hadromerids lack microscleres altogether. Hadromerid sponges are known from all oceans at all depths.
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Astrophorida Incertae Sedis
Systema Porifera, 2002Co-Authors: John N. A. Hooper, Manuel MaldonadoAbstract:Lamellomorpha Bergquist (Demospongiae, ? Astrophorida) is a monotypic genus from cool temperate and subantarctic New Zealand. It has contort oxeas, strongyles and strongyloxeas as megascleres forming a lax confused choanosomal skeleton with only slight traces of radial structure near the surface, and a skin-like membranous ectosomal skeleton packed with microstrongyles, and with streptasters (amphiaster-, metaster- and spiraster-like) scattered throughout. Its precise taxonomic allocation cannot be presently resolved, with discussion provided on possible affinities with Astrophorida (e.g., Ancorinidae, Pachastrellidae), some ‘lithistid’ demosponges (e.g., Corallistidae, Isoraphinidae, Phymaraphiniidae), Hadromerida (e.g., Alectonidae) and Halichondrida (e.g., Axinellidae, Bubaridae), and is left incertae sedis within Astrophorida.
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Family Hemiasterellidae Lendenfeld, 1889
Systema Porifera, 2002Co-Authors: John N. A. HooperAbstract:Hemiasterellidae Lendenfeld (Demospongiae, Hadromerida) contains 11 nominal genera, of which six are valid, and approximately 20 described species worldwide. Species live in all oceans, predominantly in shallow waters, are often dichotomously branching or flabellate, with hispid surface or conules and stiff texture. The family has a unique combination of euasters mainly at the surface, and monaxonic megascleres (styles and/or oxeas) with distinctly structured arrangement of axial and extra-axial skeletons. Genera are differentiated predominantly on the basis of whether megascleres are diactinal or monactinal, development of the axial and extra-axial skeletons, presence or absence of ectosomal specialisation, and euaster morphology.
Sven Zea - One of the best experts on this subject based on the ideXlab platform.
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First record of the Indo-Pacific sponge genus Rhaphidhistia (Demospongiae, Hadromerida, Trachycladidae) from the Caribbean Sea, with description of a new species
Journal of the Marine Biological Association of the United Kingdom, 2013Co-Authors: Christian M. Díaz, Sven ZeaAbstract:Exploration of continental shelves may produce unexpected faunal records. In shelf waters of La Guajira peninsula, Colombia, in the northern tip of South America, southern Caribbean Sea, we found a new species of Rhaphidhistia (Demospongiae, Hadromerida, Trachycladidae) a genus previously thought to be restricted to the Indo-Pacific Ocean. Rhaphidhistia guajiraensis sp. nov. is thickly encrusting, agglutinating bottom debris; it possesses asymmetric oxea as megascleres (465–757 μm by 6.3–17.5 μm) and spiraster-like spinispirae (15–37 μm by 2–5 μm). It is closely similar to the type species of the genus, R. spectabilis Carter, 1879, both standing apart from a third species, R. mirabilis (Dendy, 1924), thus conforming a natural group whose taxonomic placement needs to be reassessed. There are numerous cases of sponge genera with sister species in the Indo-Pacific and the Atlantic Oceans, possibly split since the Tethys Sea breakup; owing to their restricted or deep distribution, they are just starting to be discovered.
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Observations on reef coral undermining by the Caribbean excavating sponge Cliona delitrix (Demospongiae, Hadromerida)
2007Co-Authors: Andia Chaves-fonnegra, Sven ZeaAbstract:Sponges which simultaneously encrust and excavate calcareous substratum are strong space competitors in coral reefs, actively undermining and displacing live coral tissue. On Caribbean reefs, Cliona delitrix colonizes massive corals, encrusting, deeply excavating and aggressively killing entire coral heads. To establish the details of the process of colonization, excavation, undermining and death of corals by this sponge, we carried out observations on sponge-colonized corals at San Andres Island (SW Caribbean Colombia), and obtained samples for microscopical observation. As it spreads sideward, C. delitrix removed the upper few mm of the coral skeleton, maintaining its surface slightly lower than the surrounding coral, following the curved outline of the coral head. Internal excavation resulted in a solid outer supporting frame and a strongly eroded lace-like internal network. The outer frame was perforated below inhalant papillae by narrow vertical tunnels and below the large oscules by wide and deep spaces. A band of dying or dead coral surrounded the sponge. The sponge sent out a front of tissue using pioneering filaments projecting underneath the coral polyps. Long filaments may surface farther off, forming new bodies that later fuse. From microscopical observations, physical detachment of polyps was ruled out as the cause of coral death, because coral tissue displacement occurred before significant erosion of the polypar skeletal support had taken place. When sponge tissue reached underneath coral tissue, the latter remained healthy when still separated by thin skeletal barriers, but appeared as debris when barriers were broken. Live sponge and coral tissue could occur in direct contact, in which case there was accumulation of granulous cells in the coral tissue. We hypothesize that the mechanism of coral death involves close-range tissue, cell and/or biochemical interactions rather than fluid- or mucus-borne allelochemicals.
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Competition for space between encrusting excavating Caribbean sponges and other coral reef organisms
Marine Ecology Progress Series, 2006Co-Authors: Mateo López-victoria, Sven Zea, Ernesto WeilAbstract:Encrusting and excavating Caribbean sponges Cliona aprica, C. caribbaea and C. tenuis (Hadromerida: Clionaidae) aggressively undermine and displace live coral tissue. To estab- lish modes and rates of lateral advance into neighboring organisms, 171 sponge individuals were studied for 13 mo. Sponge advancement into live coral, via excavation underneath boundary polyps, occurred only when the 2 confronted at an angle of ≥180°. Sponges stopped or retreated when coral upward and inward growth at the boundary closed the angle between the coral and sponge, placing polyps out of reach of excavating tissue. At a straight angle of confrontation, C. tenuis advanced into coral at higher rates than the other 2 sponge species. Its advance was more pronounced into Diploria strigosa than into Siderastrea siderea. Sponge undermining continuously opened space for transient settlement of turf algae and for accumulation of sediments. Corallivory at the sponge-coral boundary did not imply greater rates of sponge advance, but probably did contribute to coral bioerosion. Mas- sive corals escaped sponge undermining by upward growth, their ability to do so depended partly on defensive mechanisms. Foliose and platy corals escaped by overtopping. Rates of sponge advance into substrata incrusted and overgrown by algae were in general lower than into live coral, while sponges lost space to some encrusting invertebrates.
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Storm-mediated coral colonization by an excavating Caribbean sponge
Climate Research, 2004Co-Authors: Mateo López-victoria, Sven ZeaAbstract:The broken, dead stands of the Caribbean elkhorn coral Acropora palmata, which suf- fered massive mortalities from disease and bleaching during the early 1980s, are now widely covered by Cliona tenuis, an encrusting and excavating brown sponge (Hadromerida, Clionaidae). This sponge displaces live coral tissue by undermining the polypal skeletal support. On the windward fringing reef of Islas del Rosario (Colombian Caribbean), 26% of C. tenuis individuals currently dwelling on live corals had colonized their host from sponge-carrying branches of A. palmata thrown against the corals during storms. Times of initial colonization were traced back from sponge growth rates in a few marked massive coral colonies and found to coincide approximately with hurricanes that had affected the area. Transplantation experiments confirmed that C. tenuis is able to spread to new coral hosts from attached fragments. The extent of C. tenuis dispersion via branching coral frag- ments and further massive coral colonization is now evident and, given that C. tenuis-encrusted A. palmata fragments are becoming progressively smaller, the phenomenon is likely to increase. C. tenuis was also found undermining encrusting and foliose corals settled on dead A. palmata branches, thus also retarding the process of reef recovery to an unknown degree.
Alexander Plotkin - One of the best experts on this subject based on the ideXlab platform.
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Molecular phylogenies challenge the classification of Polymastiidae (Porifera, Demospongiae) based on morphology
Organisms Diversity & Evolution, 2017Co-Authors: Alexander Plotkin, Oliver Voigt, Endre Willassen, Hans Tore RappAbstract:Polymastiidae Gray, 1867 is a worldwide distributed sponge family, which has a great significance for understanding of the demosponge deep phylogeny since the former order Hadromerida Topsent, 1894 has been recently split based on the molecular evidence and a new separate order has been established for the polymastiids. However, molecular data obtained from Polymastiidae so far are scarce, while the phylogenetic reconstruction based on morphology has faced a deficit of characters along with the vagueness of their states. The present study is a phylogenetic reconstruction of Polymastiidae based on novel data on two molecular markers, cytochrome oxidase subunit I and large subunit ribosomal DNA, obtained from a broad set of species. Monophyly of the family and nonmonophyly of four polymastiid genera are revealed, suggesting a high level of homoplasy of morphological characters, which are therefore not an appropriate base for the natural classification of Polymastiidae. Although the presented phylogenies cannot yet provide an alternative classification scheme, several strongly supported clades, which may be used as reference points in future classification, are recovered and three taxonomic actions are proposed: transfer of one species from Radiella to Polymastia Bowerbank, 1862; transfer of three species from Radiella Schmidt, 1870 to Spinularia Gray, 1867; and the consequent abandonment of Radiella .
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Polymastiidae and Suberitidae (Porifera: Demospongiae: Hadromerida) of the deep Weddell Sea, Antarctic*
Zootaxa, 2008Co-Authors: Alexander Plotkin, Dorte JanussenAbstract:The Antarctic deep-water fauna of Polymastiidae and Suberitidae is revised using recently collected material from the Weddell Sea. The former family appeared to be more abundant and diverse than the latter family in the studied area. Seven species within five polymastiid genera and three species within three suberitid genera are described. Relatively high sponge abundance at two stations deeper than 4700 m was mainly constituted by a polymastiid species Radiella antarctica sp. nov. Previously, representatives of Radiella have never been found in the Antarctic. An eurybathic species, Polymastia invaginata, well known from the Antarctic and subantarctic, appeared to be especially abundant at less than 1000 m depth. Another eurybathic polymastiid species, Tentorium cf. semisuberites, known for its bipolar distribution, was the third abundant species at the depths between 1000‐2600 m, with the highest density found at the deeper stations. Tentorium papillatum, endemic of the Southern Hemisphere, was registered only at a depth of about 1000 m. Other species studied were less abundant. Astrotylus astrotylus, the representative of the endemic Antarctic genus, was found exclusively deeper than 4500 m, often together with R. antarctica. Acanthopolymastia acanthoxa, the endemic deepwater Antarctic species, was registered at 3000 m. The discovery of suberitid Aaptos robustus sp. nov. at about 2300 m is the first signalization of Aaptos in the Antarctic and at such a considerable depth. The finding of Suberites topsenti deeper than 4700 m is also remarkable. In general the results achieved confirm the high degree of geographical endemism of the Antarctic deep-water sponge fauna and the eurybathic distribution of many Antarctic sponge species.
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alleged cosmopolitanism in sponges the example of a common arctic polymastia porifera demospongiae Hadromerida
Zoosystema, 2004Co-Authors: Alexander Plotkin, Nicole BouryesnaultAbstract:Depuis plusieurs annees le cosmopolitisme chez les especes d'eponges a ete remis en question. Nous avons etudie des populations d'une Polymastia arctique tres abondante communement identifiee a P. mamillaris (Muller, 1806). La redescription du materiel type de P. arctica (Merejkowsky, 1878) mis en synonymie avec P. mamillaris et sa comparaison avec les types de P. mamillaris et d'autres especes communes de l'Arctique et de l'Atlantique du nord-est a montre que P. arctica est une espece valide. Elle differe de P. mamillaris et P. penicillus (Montagu, 1818) par la presence d'une couche epaisse de collagene (90-180 μm) dans l'ectosome et de spicules dans les lames cellulaires des papilles, et par la formation de bourgeon au sommet des papilles. Ce resultat montre une fois de plus que le pretendu cosmopolitisme chez les eponges est du a une systematique trop conservatoire plutot qu'a une veritable homogeneite genetique.
Klaus Rützler - One of the best experts on this subject based on the ideXlab platform.
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Sponges in an extreme environment: suberitids from the quasi-marine Satonda Island crater lake (Sumbawa, Indonesia)
Journal of the Marine Biological Association of the United Kingdom, 2009Co-Authors: Andrzej Pisera, Klaus Rützler, Józef Kazmierczak, Stephan KempeAbstract:Sponges are rare in extreme environments, and very little is known about their adaptations to such settings. Evidence from two species in a marine-derived midwater stratified crater lake on Satonda Island (Sumbawa, Indonesia) suggests their production of gemmules (resting bodies), a rare trait in marine sponges but common in freshwater forms, may be a survival mechanism in the lake's harsh environment. With its epilimnion hydrochemistry—characterized by changing alkalinity, salinity, and O 2 levels over the region's wet and dry seasons—the lake sustains only a few marine macroscopic organisms, among them the suberitid sponges Protosuberites lacustris comb. nov. and Suberites sp. (Hadromerida: Suberitida). Both species belong to the same group as sponges reported from other marine-derived lakes with strongly varying and extreme environmental (especially chemical) parameters. The morphological characters, taxonomic position, ecological adaptations, environmental conditions, and biota associated with the sponges in this ecologically unique site are presented here.
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Family Placospongiidae Gray, 1867
Systema Porifera, 2002Co-Authors: Klaus RützlerAbstract:Placospongiidae Gray (Demospongiae, Hadromerida) has the typical radial skeleton structure of Hadromerida and Spirastrella -like tylostyle-spiraster spicule complement but stands out by the possession of a rigidly cemented cortex of large microscleres. The cortical spicules are ovoid or bean-shaped (selenasters) or dumbbell-like (amphinolasters). The cortex is broken up into distinctive plates that are separated by contractible grooves containing oscula and ostia. Species are encrusting or branching massive and most occur in shallow tropical and subtropical waters, from the intertidal to almost 200 m. The family, until recently considered monotypic, includes two genera, Placospongia (including Physcaphora) and Onotoa (including Amphinolana).
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Family Timeidae Topsent, 1928
Systema Porifera, 2002Co-Authors: Klaus RützlerAbstract:Timeidae Topsent (Demospongiae, Hadromerida) now contains only Timea because Diplastrella was moved to the Spirastrellidae. These sponges are thin, colorful (mostly red) crusts with choanosomal tylostyles arranged in vague tracts, ectosomal tylostyles in bouquet arrangement. Euasters occur throughout the body and form a dense layer at the surface. Species are cryptic and are found in shaded habitats of warm-temperate to tropical shallow-water environments.
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Family Acanthochaetetidae Fischer, 1970
Systema Porifera, 2002Co-Authors: Klaus Rützler, Jean VaceletAbstract:Acanthochaetetidae Fischer (Demospongiae, Hadromerida), is a largely extinct family of ‘sclerosponges’ represented by two extant species, Acanthochaetetes wellsi and Willardia caicosensis, our knowledge of which indicates its relationship to the Porifera rather than Cnidaria. The siliceous spicules of these sponges indicate close ties to the genera Spirastrella and Diplastrella but morphological peculiarities of spicules and the presence of an elaborately structured calcareous basal skeleton justifies the distinction of Acanthochaetetidae from Spirastrellidae.
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Family Clionaidae D’Orbigny, 1851
Systema Porifera, 2002Co-Authors: Klaus RützlerAbstract:Clionaidae (Demospongiae, Hadromerida) receives a new definition by accepting Spheciospongia and massive species previously assigned to Spirastrella (Spirastrellidae). A recently described genus, Cervicornia (for Alcyonium cuspidiferum Lamarck) is included here and distinguished by its specialized incurrent fistules and endopsammic choanosomal pulp. Clionaopsis new name is suggested to replace the preoccupied [Clionopsis] Thiele. Spheciospongia remains distinct for its pore sieves. All other genera are separated by their spicule complements which include tylostyles (with some oxeote or stylote modifications or additions) as megascleres, and delicate (compared to Spirastrellidae) spirasters, amphiasters, smooth and spiny microxeas, and bent or spiral, smooth or spiny microstrongyles and microrhabds as microscleres. Eight genera are considered to be valid.
Patricia Gómez - One of the best experts on this subject based on the ideXlab platform.
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Taxonomy and description of clionaid sponges (Hadromerida, Clionaidae) from the Pacific Ocean of Mexico
Zoological Journal of the Linnean Society, 2004Co-Authors: José Luis Carballo, José Antonio Cruz-barraza, Patricia GómezAbstract:A large collection of clionaid sponges collected in 58 different localities from the Pacific coast of Mexico was studied, and 15 species belonging to four genera were identified. Six species are new to science: in the genus Cliona, C. papillae sp. nov. and C. vallartense sp. nov.; in the genus Thoosa, T. calpulli sp. nov. and T. mismalolli sp. nov.; and in the genus Spheciospongia, S. ruetzleri sp. nov. and S. incrustans sp. nov. The new combinations Cliona californiana (de Laubenfels, 1932) comb. nov. and Cliona raromicrosclera (Dickinson, 1945) comb. nov. are also proposed. Pseudosuberites pseudos is considered to be synonymous to Cliona californiana. In addition, the validity of Pione mazatlanensis (Hancock, 1867) is also considered. Other Cliona species identified are Cliona vermiferaHancock, 1867, Pione carpenteri (Hancock, 1867 as Cliona carpenteri), C. amplicavataRutzler, 1974, Cliona flavifodinaRutzler, 1974, and Cliona euryphyllaTopsent, 1887. Cliona amplicavata and C. flavifodina are recorded for the first time in the Pacific Ocean and C. euryphylla for the east Pacific Ocean. The systematics, taxonomy and distribution of all these species are included and detailed species descriptions are provided based on newly collected material and previous descriptions from the literature. Discussions on problematic taxonomic issues are also presented, and the most useful parameters to differentiate species are highlighted. In addition, the morphology of the spirasters has been studied through SEM analysis, and the main characteristics have been evaluated from a taxonomic point of view in order to discriminate between species. © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society, 2004, 141, 353–397.
