Two new species in the family Axinellidae (Porifera,Demospongiae) from British Columbia and adjacent waters

Two new species of Demospongiae are described for British Columbia and adjacent waters in the family Axinellidae, Auletta krautteri sp. n. and Dragmacidon kishinensis sp. n. They represent range extensions for both of these genera. Both are fairly commonly encountered, Auletta krautteri below diving depths (87 to at least 300 m) and Dragmacidon kishinensis in shallow water (intertidal to 30 m). We propose an amended genus diagnosis for Auletta to account for the variability among species in principal spicules that form the ascending tracts to be either oxeas, styles or strongyles rather than just oxeas.     

New carnivorous sponges of the genus Abyssocladia (Demospongiae, Poecilosclerida, Cladorhizidae) from Myojin Knoll, Izu-Ogasawara Arc, southern Japan

Two new species of carnivorous sponges of the genus Abyssocladia are described. These sponges were collected from Myojin Knoll, Izu-Ogasawara (Izu-Bonin) Arc, in southern Japan. Detailed morphological observation based on specimen both in situ and preserved revealed functional differentiation of spicule distribution. Abyssocladia natsushimae sp. nov. is distinct within the genus in its mop-like gross morphology, large body size, and soft tissue packed with numerous microspined microstrongyles. Abyssocladia myojinensis sp. nov. is characterized by possession of both typical abyssochelae and palmate abyssochelae. This is the first record of the genus from Japan.     

Vertical transmission of cyanobacterial symbionts in the marine sponge Chondrilla australiensis (Demospongiae)

The cyanobacterial symbionts of the marine sponge Chondrilla australiensis (Demospongiae) were examined using fluorescent microscopy and Transmission Electron Microscopy. Unicellular cyanobacteria with ultrastructure resembling Aphanocapsa feldmannii occur in the cortex and bacterial symbionts are located throughout the mesohyl. In C. australiensis, the developing eggs are distributed throughout the mesohyl and are surrounded by nurse cells attached to them by thin filaments. The nurse cells form cytoplasmic bridges with the eggs, apparently releasing their contents into the egg cytoplasm. The presence of cyanobacterial and bacterial symbionts inside developing eggs and nurse cells in 25% of female Chondrilla australiensiswas established using Transmission Electron Microscopy, suggesting that these symbionts are sometimes passed on to the next generation of sponges via the eggs.     

First observations on egg release in the oviparous sponge Chondrilla nucula (Demospongiae, Chondrosida, Chondrillidae) in the Mediterranean Sea

Abstract. The reproduction of the demosponge Chondrilla nucula in Portofino (Ligurian Sea, Italy) was studied during August 2001. Eighteen individuals were sampled and examined with light microscopy for the presence of gametes, and 5 individuals carrying oocytes were found. In addition to microscopic observations, reproductive individuals could be easily identified as female even at the macroscopic level because of the presence of a grayish layer in the mesohyl where oocytes were concentrated. Oogenesis resulted in modifications of the external sponge morphology and of the aquiferous system. Approximately one‐third of the sponge body was filled with oocytes with the consequent disappearance of choanocyte chambers in the reproductive portion of the sponge. Under laboratory conditions, we obtained fertilized eggs from females and observed the first stages of embryonic development. Our observations suggest that fertilization in specimens of Chondrilla nucula occurs internally and not in the water. During the 2 years following these observations, no reproductive specimens were found among the same population during the reported reproductive period.     

Large expansion segments in 18S rDNA support a new sponge clade (Class Demospongiae, Order Haplosclerida)

Newly emerging molecular phylogenetic hypotheses involving the sponge Order Haplosclerida (Class Demospongiae) are far removed from traditional views on their classification using morphology. In the new grouping of marine haplosclerid taxa by molecular data all members of one highly supported clade were found to have three large indels in the 18S rRNA gene. These indels were not found in this gene in other marine haplosclerids or in any other demosponges analysed. These indels were found in the variable V4 and V7 region of the gene, had high GC contents and formed stable double stranded helices in the 18S rRNA secondary structure. These indels are very important synapomorphies, provide high support for an alternative taxonomic scheme and could help resolve the phylogeny of this order in conjunction with other phylogenetically informative characters.     

Spicule structure and affinities of the Late Ordovician hexactinellid‐like sponge Cyathophycus loydelli from the Llanfawr Mudstones Lagerstätte,Wales

Exceptionally well‐preserved specimens of the reticulosan sponge Cyathophycus loydelli from the Sandbian (Late Ordovician) Llanfawr Mudstones Formation of Llandrindod, Waes, UK, have been examined using scanning electron microscopy (SEM). The specimens include exquisitely detailed pyritized spicules, and granular pyritization of surrounding soft tissues. Spicules frequently show axial canals of diameter similar to those of modern siliceous sponges, with hexagonal symmetry typical of modern demosponges rather than hexactinellids. In one case, the axial filament is also preserved. The largest spicules (ray diameter >20 μm) show a complex structure, with a laminar external region similar to that of the extant hexactinellid Monorhaphis. Some spicules preserve sub‐micron detail of the spicule surface, resembling the reticulate collagenous sheath of Monorhaphis. The hexagonal symmetry of the canal confirms that at least some Reticulosa are not crown‐group hexactinellids, but stem‐group Hexactinellida or Demospongea, or stem‐group Silicea. This suggests that a square canal is a sufficient diagnostic feature of total‐group Hexactinellida, but that hexagonal canals were more widely distributed among Early Silicea and were probably not restricted to demosponges. Alternatively, comparison with the structure of modern verongiid fibres suggests that these may be homologous with the outer layers of Cyathophycus spicules, and Cyathophycus may instead be a stem‐group demosponge. The preserved detail of the surface layer shows that pyritization can preserve certain material with extraordinarily fine resolution.     

A reconsideration of the relationship between polyaxonid and monaxonid spicules in Demospongiae: new data from the genera Crambe and Discorhabdella (Porifera)

The relationships between different spicule lineages of Demospongiae are revised through the ontogenetic study of the main spicules of the genera Crambe and Discorhabdella. The presence of terminal orifices in the basal spines of the asterose acanthostyles of Discorhabdella, and the actines of the desmas of Crambe have been shown by examining young spicules under high magnification. Thus, the polyaxonid origin of both spicule types is hereby supported by the ontogenetic information, and their homology is also supported by their equivalent arrangement in the skeleton. The current differences in shape between both spicule types are considered the result of a divergent morphological evolution from an ancestral polyactinal corpuscle, by the atrophy/hypertrophy of a different number of actines. Arguments are also presented to support the homology of these two spicule types with the sphaeroclons of Vetulina, and other fossil genera. Moreover, the presence of axial canals inside the tubercles of the tuberose tylostyles of Discorhabdella and Crambe tuberosa indicates that the tubercles are actually atrophied actines as in the case of the hadromerid genus Terpios. According to the ontogeny, the tuberose morphology of these spicules may correspond to the retention of an ancestral characteristic in the Poecilosclerida and Hadromerida; in this case, a monophyletic origin, is suggested between both taxa. From the overall results here presented, the tetraxonid spicule, presently considered by most authors as the primitive morphotype, as well as some monaxons, could be considered as evolving from a polyaxial form.     

A late-surviving Triassic protomonaxonid sponge from the Paris Biota (Bear Lake County,Idaho, USA)

Protomonaxonid sponges are a major group of Cambrian and Ordovician fossils in exceptionally preserved (especially Burgess Shale-type) faunas, but are rare thereafter. Rare examples of apparent surviving lineages are known from the late Palaeozoic and Mesozoic, but by this time more derived groups of sponges have generally displaced them in at least shallow-water (shelf depth) ecosystems. The early Spathian (Early Triassic) Paris Biota includes abundant material of a new leptomitid protomonaxonid, Pseudoleptomitus advenus Botting nov. gen., nov. sp., distinguished by having an unbundled longitudinal skeleton and very weak transverse component. This is the first post-Ordovician leptomitid known, and indicates long-term survival of the group in unknown environments. Its occurrence near storm wave base is similar to the preferred environment of earlier examples of the family, suggesting either ecological rarity or taphonomic reasons for their ∼200-million-year absence from later Palaeozoic rocks.     

Phagocytosis of sperm by follicle cells of the carnivorous sponge Asbestopluma occidentalis (Porifera, Demospongiae)

During spermatogenesis of the carnivorous sponge Asbestopluma occidentalis, follicle cells that lined the spermatocysts phagocytosed unreleased mature sperm. Such follicle cells are part of the complex envelope that limits spermatocysts of A. occidentalis, which is also comprised of a collagen layer, a thick layer of intertwined cells, and spicules. Follicle cells showed vesicles containing single phagocytosed spermatozoa within their cytoplasm. Additionally, lipids and other inclusions were observed within the cytoplasm of follicle cells. It is likely that follicle cells recapture nutrients by phagocytosing spermatozoa and use them to form lipids and other inclusions. Such sperm phagocytosis is usually performed in higher invertebrates and vertebrates by Sertoli cells that are located in the testis wall. While Sertoli cells develop a wide range of functions such as creating a blood-testis barrier, providing crucial factors to ensure correct progression of spermatogenesis, and phagocytosis of aberrant, degenerating, and unreleased sperm cells, sponge follicle cells may only display phagocytotic activity on spermatogenic cells.     

Regional and local controls on postglacial vegetation and fire in the Siskiyou Mountains, northern California, USA

The Siskiyou Mountains of northwestern California and southwestern Oregon are a floristic hotspot, and the high diversity of conifers there likely results from a combination of geological, ecological, climatological and historical factors. To evaluate how past climate variability has influenced the composition, structure and fire regime of the Siskiyou forests, pollen, charcoal, and lithological evidence was examined from two lakes along a moisture gradient to reconstruct the vegetation, fire and climate history. The late-glacial period was characterized by subalpine parkland and infrequent fire at both sites. During the late-glacial/Early Holocene transition period, subalpine parkland was replaced by a closed forest of Pinus, Cupressaceae, Abies and Pseudotsuga and more frequent fires a 1000 years earlier at the wetter site, and it is likely that reduced Pacific Ocean upwelling created warmer drier conditions at the coast. In the Early Holocene, Pinus, Cupressaceae were less abundant and fire less frequent at the coastal site during a period of increased coastal upwelling and fog production. In the Late Holocene, Abies, Pseudotsuga, Pinus, and Quercus vaccinifolia increased in the forest at both sites suggesting a widespread response to cooling. Fewer fires at the wetter site may account for the abundance of Picea breweriana within the last 1000 years. The comparison of the two records implies that large-scale controls in climate during the last 14,000 cal yr BP have resulted in major changes in vegetation and fire regime. Asynchrony in the ecosystem response of wetter and drier sites arises from small-scale spatial variations in effective moisture and temperature resulting from topographically-influenced microclimates and coastal-to-inland climate gradients.     

Fedomia mikhaili—A new spicule-bearing organism of sponge grade from the Vendian (Ediacaran) of the White Sea, Russia

The Vendian fossil locality on the Solza River is one of the most productive in the White Sea Region. The fossiliferous deposits belong to the Upper Vendian Verkhovka Formation correlated lithologically with strata dated at 558 ± 1 to 555.3 ± 0.3 Ma in adjacent regions. This locality is characterized by yielding more than 10 well-represented Ediacaran genera. Elongated imprints of Fedomia mikhaili, n. gen. et n. sp., are common at the Solza River fossil locality. The new taxon is characterized by its six- to eight-rayed star-shaped concave structures with diameters of 2–5 mm. The organism can be reconstructed with sacciform thin-walled body attached basally to the substrate. The star-shaped structures may be spicules that appear to be rather flexible than rigid. The new genus, Fedomia, shows some similarities to Eiffelia Walcott, 1920 from the Middle Cambrian of British Columbia, and thus is interpreted as an organism of sponge grade. The new taxon could represent an additional phylogenetic link between the Ediacaran and Cambrian worlds.     

A new genus and species of deep-sea glass sponge (Porifera, Hexactinellida, Aulocalycidae) from the Indian Ocean

New hexactinellid sponges were collected from 2589 m depth on the Carlsberg Ridge in the Indian Ocean during deep-sea dredging. All fragments belong to a new genus and species, Indiellagen. n.ridgenensissp. n., a representative of the family Aulocalycidae described here. The peculiar features of this sponge, not described earlier for other Aulocalycidae, are: longitudinal strands present in several layers and epirhyses channelization.     

A new species of Polymastia (Porifera, Hadromerida, Polymastiidae) from the Aleutian Islands, Alaska, USA

Polymastia fluegeli n. sp. is described from deep water off the Aleutian Islands (Alaska, USA). P. fluegeli is disc-shaped and lives partly buried in the sediment, with only the papillae protruding above the surface. This new species has a basal layer of agglutinated sediment particles occurring between the choanosome and the ectosomal lower layer. This conspicuous sediment layer is not described for other species of Polymastia. Occurring spicule types and sizes are different from known species of the area.     

The extent of asexual reproduction in sponges of the genus Chondrilla (Demospongiae: Chondrosida) from the Caribbean and the Brazilian coasts

In this study, we estimated the extent of asexual reproduction and genotypic diversity at the intra- and interspecific levels in sponges of the genus Chondrilla in the Caribbean and along the coast of Brazil. Allozymes were used to identify the genotypes of specimens of Chondrilla in each location. The four species studied displayed a large variation in the extent of clonal reproduction and genotypic diversity, with the two species from the Bahamas having a greater proportion of asexually produced individuals than those along the coast of Brazil. Conspecific Brazilian populations of Chondrilla sp. had large differences in clonality: the population from a heterogeneous environment and under the influence of a strong upwelling had little clonality (7%), whereas the population located 350 km south along the coast, in a more homogeneous and temporally stable environment, had a five-fold larger (39%) proportion of asexually derived individuals. Finally, we were able to confirm that, besides fission, the genus Chondrilla displays a second mode of asexual reproduction, by fragmentation of teardrop shaped individuals.     

Investigation of the budding process in Tethya citrina and Tethya aurantium (Porifera, Demospongiae)

The budding process has been studied in two congeneric Mediterranean species belonging to Tethya from different sampling sites: Marsala and Venice Lagoons (Tethya citrina); Marsala Lagoon and Porto Cesareo Basin (Tethya aurantium). Buds, connected to the adult by a spiculated stalk, differ between the two species in morphology and size, since those of T. citrina are small with elongated bodies, showing only a few spicules protruding from the apical region, whereas those of T. aurantium are round, larger, and show spicules radiating from the peripheral border. In T. citrina, cells with inclusions, varying in electron density and size, represent the main cell types of the buds. In T. aurantium, the cell component shows a major diversification, resulting from spherulous cells, grey cells, vacuolar cells and peculiar micro-vesicle cells. Neither canals nor choanocyte chambers were observed in the buds of the two species. In T. citrina, bud production is similar in both sampling sites. In T. aurantium, budding occurs more rarely in Porto Cesareo Basin, probably in relation with environmental factors, such as the covering of the cortex by sediment and micro-algae. Finally, in the buds of both species, the spicule size does not differ from that of the cortex of the adult sponges, further supporting the main involvement of the cortex in organizing the skeletal architecture of the buds.     

A new clionaid sponge infests live corals on the west coast of India (Porifera,Demospongiae, Clionaida)

Coral reef ecosystems depend on the balanced interplay of constructive and destructive processes and are increasingly threatened by environmental change. In this context bioeroding sponges play a significant role in carbonate cycling and sediment production. They occasionally aggravate erosional processes on disturbed reefs. Like other coral ecosystems, Indian reefs have suffered from local and global effects. However, the systematic affiliation and diversity of many Indian bioeroding sponges and their infestation rates are largely confused or unknown. The present study describes a new bioeroding sponge species, Cliona thomasi sp. nov. from the central west coast of India. It belongs to the Cliona viridis species complex, displaying the key characters of tylostyles and spirasters, as well as harbouring photosymbiotic dinoflagellates. Specific morphological characteristics and molecular data from nrITS1 DNA and 28S rDNA distinguished C. thomasi sp. nov. from other known C. viridis complex and a number of Spheciospongia species. The historic sample of ‘Suberites coronarius’ from Mergui Archipelago (sensu Carter, 1887 Carter, H. J. (1887). Report on the marine sponges, chiefly from King Island, in the Mergui Archipelago, collected for the trustees of the Indian museum, Calcutta, by Dr. John Anderson, F. R. S., superintendent of the museum. Zoological Journal of the Linnean Society, 21, 61–84. https://doi.org/10.1111/j.1096-3642.1887.tb00381.x[Crossref] , [Google Scholar]), but not from the Caribbean (sensu Carter, 1882 Carter, H. J. (1882). Some sponges from the West Indies and Acapulco, in the Liverpool Free Museum, described with general and classificatory remarks. Annals and Magazine of Natural History, 9, 266–301, 346–368, pls. XI-XII. https://doi.org/10.1080/00222938209459039[Taylor &; Francis Online] , [Google Scholar]), is conspecific with C. thomasi sp. nov. Cliona thomasi sp. nov. is locally very abundant, appears to be a key bioeroder, and thus regular monitoring of its abundance, distribution and infestation patterns is recommended.     

A probable hyalonematid sponge (Hexactinellida: Amphidiscophora) from the Middle Ordovician of the Builth Inlier,Wales

Modern hexactinellid sponges are diverse, but almost exclusively deep-marine organisms with a very intermittent fossil record. Aside from the fused skeletons of hexactinosan lineages (which are also exceptionally rare in Palaeozoic sediments), identifying other families is challenging due to the microscopic nature of many diagnostic characters, and the need for exceptional preservation in a deep-water palaeoenvironment. Among the more distinctive living families is the Hyalonematidae, which have several preservable diagnostic features. A new sponge (Nectocollare zakdouli n. gen. n. sp.) from the Middle Ordovician Castle Bank fauna of Wales, UK, shows several of these characters, including pinular pentactine dermalia, unbundled choanosomal diactins, and a reticulate marginal rim at the apex. No root tuft is preserved, but these are often detached from fossil sponges. Although there remains some uncertainty over the assignment to Hyalonematidae, this sponge represents the only probable example from the Palaeozoic. Even in the absence of diagnostic microscleres, it likely represents a derived, crown-group hexactinellid, and further confirms the diversification of the class during the earliest Palaeozoic.     

Purification and in vitro cultivation of archaeocytes (stem cells) of the marine sponge <Emphasis Type="Italic">Hymeniacidon perleve</Emphasis> (Demospongiae)

Marine sponges (Porifera) are the best source of marine bioactive metabolites for drug discovery and development, although the sustainable production of most sponge-derived metabolites remains a difficult task. In vitro cultivation of sponge cells in bioreactors has been proposed as a promising technology. However, no continuous cell line has as yet been developed. Archaeocytes are considered to be toti/multipotent stem cells in sponges and, when purified, may allow the development of continuous sponge cell lines. As a prerequisite, we have developed a novel four-step protocol for the purification of archaeocytes from a marine sponge, Hymeniacidon perleve: (1) differential centrifugation to separate large sponge cells including archaeocytes; (2) selective agglomeration in low-Ca²⁺/Mg²⁺ artificial seawater in which living archaeocytes form small loose aggregates with some pinacocytes and collencytes; (3) differential adherence to remove anchorage-dependent pinacocytes, collencytes and other mesohyl cells; (4) Ficoll-Vrografin density gradient centrifugation to purify archaeocytes. The final purity of archaeocytes is greater than 80%. The proliferation potential of the archaeocytes has been demonstrated by high levels of BrdU incorporation, PCNA expression and telomerase activity. In 4-day primary cultures, the purified archaeocytes show a 2.5-fold increase in total cell number. This study opens an important avenue towards developing sponge cell cultures for the commercial exploitation of sponge-derived drugs. The authors are grateful for the financial support of the Chinese Academy of Sciences under the “100 Talent Project”, the “Innovation Fund” from the Dalian Institute of Chemical Physics, the “Hi-Tech Research and Development Program of China” (2001AA620404), and the European Commission (project: Silicon Biotechnology).