Siliceous Sponge-Microbe Biotic Associations and Their Recurrence through the Phanerozoic as Reef Mound Constructors

Late Ordovician radiolarians are described from allochthonous limestone breccia deposits of the graptolitic Malongulli Formation of central New South Wales. Included among the forms are the new ‘palaeoactinommid’ genus Kalimnasphaera with new species K. maculosa, the new entactiniid species, Entactinia subulata, and the new anakrusid species, Auliela taplowensis. A number of other entactiniids and the first recorded Ordovician ‘rotasphaerids’ are placed in open nomenclature. Graptolite faunas of the Malongulli Formation indicate that the deposits range in age from the Eastonian Zone of Dicranograptus hians kirki to the Bolindian Zone of Climacograptus uncinatus, that is, from latest Caradoc to early or middle Ashgill in age. This is only the second known well-preserved radiolarian assemblage to be illustrated from Late Ordovician (late Caradoc–Ashgill) successions, and the earliest known from Australia. The radiolarians typically occur in tabularly shaped, laminated lime-mudstone clasts with an abundance of siliceous sponge remains. These clasts appear to be formed from peri-platform ooze of the ‘deeper-water’ slope facies, which became incorporated in debris flows moving into the adjoining basin.

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Sponge diversity and community composition in Irish bathyal coral reefs

Contributions to Zoology ◽

10.1163/18759866-07602005 ◽

2007 ◽

Vol 76 (2) ◽

pp. 121-142 ◽

Cited By ~ 41

Author(s):

Rob W.M. van Soest ◽

Daniel F.R. Cleary ◽

Mario J. de Kluijver ◽

Marc S.S. Lavaleye ◽

Connie Maier ◽

...

Keyword(s):

Cluster Analysis ◽

Species Richness ◽

Coral Reefs ◽

Community Composition ◽

Live Coral ◽

The West ◽

Sponge Diversity ◽

And Cluster Analysis ◽

Pooled Samples ◽

Reef Mound

Sponge diversity and community composition in bathyal cold water coral reefs (CWRs) were examined at 500-900 m depth on the southeastern slopes of Rockall Bank and the northwestern slope of Porcupine Bank, to the west of Ireland in 2004 and 2005 with boxcores. A total of 104 boxcore samples, supplemented with 10 trawl/dredge attempts, were analyzed for the presence and abundance of sponges, using microscopical examination of (sub)samples of collected coral branches, and semi-quantitative macroscopic examination. Approximate minimum size of identified and counted sponge individuals was 1 mm. Literature data were added to the Porcupine Bank results to compensate for a less intensive sampling program in that location. Species richness and abundance were determined at local (sample diversity, pooled-sample diversity, local reef diversity), between-reef (diversity of two reef areas at 15 km distance), and regional scales (diversity of three reef areas over a distance of 200 km). Abiotic and biotic parameters including depth, the presence and cover of live coral, dead coral and sand, local reef, and orientation towards the nearest reef mound summit, were included in a constrained ordination technique (RDA); a Monte Carlo forward selection procedure was used to obtain significant predictors of variation in composition. The results of this analysis were compared with unconstrained ordination (PCA) and cluster analysis. The presence of live coral, depth and the local reefs C1 and C3 proved to be significant predictors of variation in sponge composition. The PCA and cluster analysis confirmed these results. Sample species richness was consistently heterogeneous from zero species and individuals up to 57 species and 90 individuals per (boxcore) sample. Species richness of local reefs determined from pooled samples showed the three localities studied to have similar species richness, namely 105-122 species in each location. Species richness was highest in samples with relatively low live coral cover. As in the RDA, live coral presence and depth appeared to be responsible for most of the variation observed in the cluster results. Cluster analysis of Bray-Curtis dissimilarity values of the pooled samples of all three reef localities using presence/absence data of all available samples indicated that distance appeared to structure the composition of the sponge assemblages of the three reef mound areas, but much less so within and among local reefs. Bathyal reefs of the regions to the west of Ireland were found to have a combined sponge species richness of 191 species, exceeding the richness of individual reef mound areas by c. 38-45%. Sponge presence in CWRs is clearly structured and controlled by biotic and abiotic factors. In particular, live coral presence appears a significant predictor of CWR sponge composition and diversity.

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Siliceous sponge expansion and phosphogenesis in a shallow water environment in the Malyi Karatau Range (Kazakhstan) during the Precambrian-Cambrian transition

Precambrian Research ◽

10.1016/j.precamres.2020.105830 ◽

2020 ◽

Vol 347 ◽

pp. 105830

Author(s):

Michael Tatzel ◽

Maria Stuff ◽

Gerhard Franz ◽

Dorothee Hippler ◽

Uwe Wiechert ◽

...

Keyword(s):

Shallow Water ◽

Water Environment ◽

Siliceous Sponge ◽

Shallow Water Environment

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Architecture and Paleoenvironment of Mid-Jurassic Microbial–Siliceous Sponge Mounds, Northeastern Spain

Journal of Sedimentary Research ◽

10.2110/jsr.2019.5 ◽

2019 ◽

Vol 89 (2) ◽

pp. 110-134

Author(s):

Sara Tomás ◽

Marcos Aurell ◽

Beatriz Bádenas ◽

Merle Bjorge ◽

María Duaso ◽

...

Keyword(s):

Siliceous Sponge

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