There are few sponges known from the end-Ordovician to early-Silurian strata all over the world, ... more There are few sponges known from the end-Ordovician to early-Silurian strata all over the world, and no records of sponge fossils have been found yet in China during this interval. Here we report a unique sponge assemblage spanning the interval of the end-Ordovician mass extinction from the Kaochiapien Formation (Upper Ordovician-Lower Silurian) in South China. This assemblage contains a variety of well-preserved siliceous sponges, including both Burgess Shale-type and modern type taxa. It is clear that this assemblage developed in deep water, low energy ecosystem with less competitors and more vacant niches. Its explosion may be related to the euxinic and anoxic condition as well as the noticeable transgression during the end-Ordovician mass extinction. The excellent preservation of this assemblage is probably due to the rapid burial by mud turbidites. This unusual sponge assemblage provides a link between the Burgess Shale-type deep water sponges and the modern forms. It gives an ...
... sponge fossil, collected by R. Bromley from the Arnager Limestone Formation, on Bornholm, Den... more ... sponge fossil, collected by R. Bromley from the Arnager Limestone Formation, on Bornholm, Denmark. ... View larger version (126K): [in this window] [in a new window], FIGURE 7Prostalia ... rays between 0.8 and 1.2 mm long, project approximately 0.30.6 mm beyond outer wall ...
In this study we found 28 species, 6 new to science, from 17 genera and 11 families. Four familie... more In this study we found 28 species, 6 new to science, from 17 genera and 11 families. Four families: Aphrocallistidae, Rossellidae, Monorhaphididae and Euretidae have not been reported from the Australian seas before. Revision of the famous 'Venus-flower basket' Euplectella aspergillum has accompanied this investigation, which led to designation of the following subspecies defined by specific features and various geographical
New Hexactinellida from the deep Weddell Sea collected in 2005 during the ANT XXII/3 expedition (... more New Hexactinellida from the deep Weddell Sea collected in 2005 during the ANT XXII/3 expedition (ANDEEP III ) are described. This hexactinellid fauna includes 12 species from 8 genera, 2 of which are new to science: Lophocalyx profundum n. sp. and L. topsenti n. sp. It further contains the first record of Caulophacus (Caulodiscus) valdiviae in the Weddell Sea, and
Reconciliation of paleontological and molecular phylogenetic evidence holds great promise for a b... more Reconciliation of paleontological and molecular phylogenetic evidence holds great promise for a better understanding of the temporal succession of cladogenesis and character evolution, especially for taxa with a fragmentary fossil record and uncertain classification. In zoology, studies of this kind have largely been restricted to Bilateria. Hexactinellids (glass sponges) readily lend themselves to test such an approach for early-branching (non-bilaterian) animals: they have a long and rich fossil record, but for certain taxa paleontological evidence is still scarce or ambiguous. Furthermore, there is a lack of consensus for taxonomic interpretations, and discrepancies exist between neontological and paleontological classification systems. Using conservative fossil calibration constraints and the largest molecular phylogenetic data set assembled for this group, we infer divergence times of crown-group Hexactinellida in a Bayesian relaxed molecular clock framework. With some notable exceptions, our results are largely congruent with interpretations of the hexactinellid fossil record, but also indicate long periods of undocumented evolution for several groups. This study illustrates the potential of an integrated molecular/paleobiological approach to reconstructing the evolution of challenging groups of organisms.
In this study we provide evidence that the species Rossella podagrosa Kirkpatrick, 1907, commonly... more In this study we provide evidence that the species Rossella podagrosa Kirkpatrick, 1907, commonly considered a synonym of Rossella racovitzae Topsent, 1901, is truly a valid species. We show that it can be clearly distinguished from other species especially when taking into consideration the in situ habitus of the sponge in combination with the spicules. Furthermore we demonstrate the weaknesses in the so far published synonymy concept for the very complicated genus Rossella Carter, 1872. From this we conclude that the best strategy for further analysis of Rossella and establishment of acceptable synonymies will need to be based on detailed examination of the spicules, the holotypes, and in situ habitus. When possible it will be useful to analyze specimens from all Antarctic oceanographic regions.
Regional warming in the western sector of the Antarctic has been observed since the 1950s. In 199... more Regional warming in the western sector of the Antarctic has been observed since the 1950s. In 1995, this warming led to the collapse of the Larsen A ice-shelf, followed by the Larsen B ice shelf in 2002. Research expeditions in 2007, 2011, and 2013 were conducted by a multi-disciplinary team to track and monitor the ecological and oceanographic changes in this region, both from the former Larsen AB ice-shelves, but also from the still intact Larsen C ice-shelf and the adjacent Antarctic Peninsula. Sponges play a key role in Southern Ocean benthic communities, important both for biomass and as habitat for many other organisms. Recent studies utilising ROV (Remotely Operated Vehicle) in this region have shown that glass sponges have rapidly increased their abundance after ice-shelf collapse. This project aims to taxonomically identify all sponges collected in these expeditions to determine the biological diversity of these communities and how, during this time period, they have ecolog...
Sponges play a key role in Antarctic marine benthic community structure, forming heterogeneous ha... more Sponges play a key role in Antarctic marine benthic community structure, forming heterogeneous habitats supporting rich benthic communities. Compiling, reviewing and analysing new sponge data enables us to better understand regional benthic biodiversity patterns in this region. Two new complementary syntheses of Southern Ocean sponge research have been produced to provide an up-to-date benchmark of biogeographic knowledge at the end of the successful CAML (Census of Antarctic Marine Life) program. The first publication provides an updated biogeographic review of Southern Hemisphere high-latitude sponges, assessing over 10,000 distribution records (Downey et al. 2012). The second publication reviews and summarises the key advances in Southern Ocean sponge research, highlighting new knowledge gained in the areas of taxonomy, ecology, habitat importance, and biogeography in the last 40 years (Janussen & Downey, 2014).
Bibliographische Information der Deutschen Nationalbibliothek Die Deutsche Nationalbibliothek ver... more Bibliographische Information der Deutschen Nationalbibliothek Die Deutsche Nationalbibliothek verzeichnet diese Publikation in der Deutschen Nationalbibliographie; detaillierte bibliographische Daten sind im Internet über <http://dnb.ddb.de> abrufbar.
Molecular systematic studies have indicated that the hexactinellid sponge species Rossella nodast... more Molecular systematic studies have indicated that the hexactinellid sponge species Rossella nodastrella Topsent (Lyssacinosida, Rossellidae), previously only known from the NE Atlantic, is only distantly related to its congeners, which are restricted to the Southern Ocean, representing the only case thus far reported of a diphyletic genus in the class Hexactinellida. Here we describe new material of "Rossella" nodastrella from cold-water coral reefs in the NW Atlantic (Florida). Morphological comparison with the holotype from the Azores and specimens recently reported from off Ireland reveal at least two distinct species, which we corroborate with molecular data. Because the diphyletic nature of "Rossella" is further supported with inclusion of the new specimens in the molecular phylogeny, we erect a new genus, Nodastrella gen. nov., for these two species. The Irish specimens are synonymized with our new species Nodastrella asconemaoida sp. nov. Subtle morphological and molecular differences between the E and W Atlantic specimens are for the time being ascribed to intraspecific geographic variation, but indicate that Nodastrella might contain more (sub)species, pending investigation of additional specimens, especially from intermediate locations.
Page 1. CHAPTER 10 Southern Ocean Deep Benthic Biodiversity A. Brandt1, C. De Broyer2, B. Ebbe3, ... more Page 1. CHAPTER 10 Southern Ocean Deep Benthic Biodiversity A. Brandt1, C. De Broyer2, B. Ebbe3, KE Ellingsen4, AJ Gooday5, D. Janussen6, S. Kaiser1, K. Linse7, M. Schueller8, MRA Thomson9, PA Tyler5, and A. Vanreusel10 ...
The under-explored abyssal depths of the Kurile–Kamchatka region have been re-examined during the... more The under-explored abyssal depths of the Kurile–Kamchatka region have been re-examined during the KuramBio (Kurile–Kamchatka Biodiversity Study) expedition.
Deep Sea Research Part II: Topical Studies in Oceanography, 2014
Eastern Weddell--Sea, Antarc;ca, during the ANT XXIV--2 (SYSTCO I) expedi;on of RV Polarstern. Al... more Eastern Weddell--Sea, Antarc;ca, during the ANT XXIV--2 (SYSTCO I) expedi;on of RV Polarstern. All sponges analyzed in here were sampled by an Agassiz trawl (AGT) and originate from the sponge--rich sta;on 48--1 on the deep Ekström Shelf, situated in 602.1 m depth (Figure 1). We analyzed associated infauna of fiVeen individuals of the sponge species Mycale (Oxymycale) acerata Kirkpatrick, 1907 (Demospongiae: Mycalina), Rossella antarc4ca Carter, 1872 and R. racovitzae Topsent, 1901 (both Hexac;nellida: Lyssacinosida) (Figure 2).
There are few sponges known from the end-Ordovician to early-Silurian strata all over the world, ... more There are few sponges known from the end-Ordovician to early-Silurian strata all over the world, and no records of sponge fossils have been found yet in China during this interval. Here we report a unique sponge assemblage spanning the interval of the end-Ordovician mass extinction from the Kaochiapien Formation (Upper Ordovician-Lower Silurian) in South China. This assemblage contains a variety of well-preserved siliceous sponges, including both Burgess Shale-type and modern type taxa. It is clear that this assemblage developed in deep water, low energy ecosystem with less competitors and more vacant niches. Its explosion may be related to the euxinic and anoxic condition as well as the noticeable transgression during the end-Ordovician mass extinction. The excellent preservation of this assemblage is probably due to the rapid burial by mud turbidites. This unusual sponge assemblage provides a link between the Burgess Shale-type deep water sponges and the modern forms. It gives an ...
... sponge fossil, collected by R. Bromley from the Arnager Limestone Formation, on Bornholm, Den... more ... sponge fossil, collected by R. Bromley from the Arnager Limestone Formation, on Bornholm, Denmark. ... View larger version (126K): [in this window] [in a new window], FIGURE 7Prostalia ... rays between 0.8 and 1.2 mm long, project approximately 0.30.6 mm beyond outer wall ...
In this study we found 28 species, 6 new to science, from 17 genera and 11 families. Four familie... more In this study we found 28 species, 6 new to science, from 17 genera and 11 families. Four families: Aphrocallistidae, Rossellidae, Monorhaphididae and Euretidae have not been reported from the Australian seas before. Revision of the famous 'Venus-flower basket' Euplectella aspergillum has accompanied this investigation, which led to designation of the following subspecies defined by specific features and various geographical
New Hexactinellida from the deep Weddell Sea collected in 2005 during the ANT XXII/3 expedition (... more New Hexactinellida from the deep Weddell Sea collected in 2005 during the ANT XXII/3 expedition (ANDEEP III ) are described. This hexactinellid fauna includes 12 species from 8 genera, 2 of which are new to science: Lophocalyx profundum n. sp. and L. topsenti n. sp. It further contains the first record of Caulophacus (Caulodiscus) valdiviae in the Weddell Sea, and
Reconciliation of paleontological and molecular phylogenetic evidence holds great promise for a b... more Reconciliation of paleontological and molecular phylogenetic evidence holds great promise for a better understanding of the temporal succession of cladogenesis and character evolution, especially for taxa with a fragmentary fossil record and uncertain classification. In zoology, studies of this kind have largely been restricted to Bilateria. Hexactinellids (glass sponges) readily lend themselves to test such an approach for early-branching (non-bilaterian) animals: they have a long and rich fossil record, but for certain taxa paleontological evidence is still scarce or ambiguous. Furthermore, there is a lack of consensus for taxonomic interpretations, and discrepancies exist between neontological and paleontological classification systems. Using conservative fossil calibration constraints and the largest molecular phylogenetic data set assembled for this group, we infer divergence times of crown-group Hexactinellida in a Bayesian relaxed molecular clock framework. With some notable exceptions, our results are largely congruent with interpretations of the hexactinellid fossil record, but also indicate long periods of undocumented evolution for several groups. This study illustrates the potential of an integrated molecular/paleobiological approach to reconstructing the evolution of challenging groups of organisms.
In this study we provide evidence that the species Rossella podagrosa Kirkpatrick, 1907, commonly... more In this study we provide evidence that the species Rossella podagrosa Kirkpatrick, 1907, commonly considered a synonym of Rossella racovitzae Topsent, 1901, is truly a valid species. We show that it can be clearly distinguished from other species especially when taking into consideration the in situ habitus of the sponge in combination with the spicules. Furthermore we demonstrate the weaknesses in the so far published synonymy concept for the very complicated genus Rossella Carter, 1872. From this we conclude that the best strategy for further analysis of Rossella and establishment of acceptable synonymies will need to be based on detailed examination of the spicules, the holotypes, and in situ habitus. When possible it will be useful to analyze specimens from all Antarctic oceanographic regions.
Regional warming in the western sector of the Antarctic has been observed since the 1950s. In 199... more Regional warming in the western sector of the Antarctic has been observed since the 1950s. In 1995, this warming led to the collapse of the Larsen A ice-shelf, followed by the Larsen B ice shelf in 2002. Research expeditions in 2007, 2011, and 2013 were conducted by a multi-disciplinary team to track and monitor the ecological and oceanographic changes in this region, both from the former Larsen AB ice-shelves, but also from the still intact Larsen C ice-shelf and the adjacent Antarctic Peninsula. Sponges play a key role in Southern Ocean benthic communities, important both for biomass and as habitat for many other organisms. Recent studies utilising ROV (Remotely Operated Vehicle) in this region have shown that glass sponges have rapidly increased their abundance after ice-shelf collapse. This project aims to taxonomically identify all sponges collected in these expeditions to determine the biological diversity of these communities and how, during this time period, they have ecolog...
Sponges play a key role in Antarctic marine benthic community structure, forming heterogeneous ha... more Sponges play a key role in Antarctic marine benthic community structure, forming heterogeneous habitats supporting rich benthic communities. Compiling, reviewing and analysing new sponge data enables us to better understand regional benthic biodiversity patterns in this region. Two new complementary syntheses of Southern Ocean sponge research have been produced to provide an up-to-date benchmark of biogeographic knowledge at the end of the successful CAML (Census of Antarctic Marine Life) program. The first publication provides an updated biogeographic review of Southern Hemisphere high-latitude sponges, assessing over 10,000 distribution records (Downey et al. 2012). The second publication reviews and summarises the key advances in Southern Ocean sponge research, highlighting new knowledge gained in the areas of taxonomy, ecology, habitat importance, and biogeography in the last 40 years (Janussen & Downey, 2014).
Bibliographische Information der Deutschen Nationalbibliothek Die Deutsche Nationalbibliothek ver... more Bibliographische Information der Deutschen Nationalbibliothek Die Deutsche Nationalbibliothek verzeichnet diese Publikation in der Deutschen Nationalbibliographie; detaillierte bibliographische Daten sind im Internet über <http://dnb.ddb.de> abrufbar.
Molecular systematic studies have indicated that the hexactinellid sponge species Rossella nodast... more Molecular systematic studies have indicated that the hexactinellid sponge species Rossella nodastrella Topsent (Lyssacinosida, Rossellidae), previously only known from the NE Atlantic, is only distantly related to its congeners, which are restricted to the Southern Ocean, representing the only case thus far reported of a diphyletic genus in the class Hexactinellida. Here we describe new material of "Rossella" nodastrella from cold-water coral reefs in the NW Atlantic (Florida). Morphological comparison with the holotype from the Azores and specimens recently reported from off Ireland reveal at least two distinct species, which we corroborate with molecular data. Because the diphyletic nature of "Rossella" is further supported with inclusion of the new specimens in the molecular phylogeny, we erect a new genus, Nodastrella gen. nov., for these two species. The Irish specimens are synonymized with our new species Nodastrella asconemaoida sp. nov. Subtle morphological and molecular differences between the E and W Atlantic specimens are for the time being ascribed to intraspecific geographic variation, but indicate that Nodastrella might contain more (sub)species, pending investigation of additional specimens, especially from intermediate locations.
Page 1. CHAPTER 10 Southern Ocean Deep Benthic Biodiversity A. Brandt1, C. De Broyer2, B. Ebbe3, ... more Page 1. CHAPTER 10 Southern Ocean Deep Benthic Biodiversity A. Brandt1, C. De Broyer2, B. Ebbe3, KE Ellingsen4, AJ Gooday5, D. Janussen6, S. Kaiser1, K. Linse7, M. Schueller8, MRA Thomson9, PA Tyler5, and A. Vanreusel10 ...
The under-explored abyssal depths of the Kurile–Kamchatka region have been re-examined during the... more The under-explored abyssal depths of the Kurile–Kamchatka region have been re-examined during the KuramBio (Kurile–Kamchatka Biodiversity Study) expedition.
Deep Sea Research Part II: Topical Studies in Oceanography, 2014
Eastern Weddell--Sea, Antarc;ca, during the ANT XXIV--2 (SYSTCO I) expedi;on of RV Polarstern. Al... more Eastern Weddell--Sea, Antarc;ca, during the ANT XXIV--2 (SYSTCO I) expedi;on of RV Polarstern. All sponges analyzed in here were sampled by an Agassiz trawl (AGT) and originate from the sponge--rich sta;on 48--1 on the deep Ekström Shelf, situated in 602.1 m depth (Figure 1). We analyzed associated infauna of fiVeen individuals of the sponge species Mycale (Oxymycale) acerata Kirkpatrick, 1907 (Demospongiae: Mycalina), Rossella antarc4ca Carter, 1872 and R. racovitzae Topsent, 1901 (both Hexac;nellida: Lyssacinosida) (Figure 2).
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