Taxonomy of some Indian and Pacific oceans Corticium, with the description of three new species from Western Australia (Porifera: Homosclerophorida).

The sponge genus Corticium has important evolutionary significance and great pharmacological potential, but its diversity remains poorly known. In this contribution we redescribe two poorly-known Indian and Pacific oceans species, viz., Corticium simplex and C. bargibanti, and describe three new species of Corticium from Western Australia. We observed for the first time the presence of rare calthrops in C. simplex, which has a wide distribution and may be a species complex. The three new species are mainly characterized by their spiculation: Corticium furcatum sp. nov. has large calthrops and exclusive candelabra with bifurcated rays in the apical actine; C. monolophum sp. nov. has large monolophose calthrops, smooth calthrops and candelabra; and C. verticillatum sp. nov. has acanthocalthrops with verticillated spines, which are exclusive to this species within the genus. The diversity of Corticium is raised to 11 species worldwide, but it still remains highly underestimated. A key to all valid species is here provided.

How a collaborative integrated taxonomic effort has trained new spongiologists and improved knowledge of Martinique Island (French Antilles, eastern Caribbean Sea) marine biodiversity.

Although sponges are important components of benthic ecosystems of the Caribbean Sea, their diversity remained poorly investigated in the Lesser Antilles. By organizing a training course in Martinique, we wanted both to promote taxonomy and to provide a first inventory of the sponge diversity on this island. The course was like a naturalist expedition, with a field laboratory and a classroom nearby. Early-career scientists and environmental managers were trained in sponge taxonomy. We gathered unpublished data and conducted an inventory at 13 coastal sites. We explored only shallow water habitats (0-30 m), such as mangroves, reefs or rocky bottoms and underwater caves. According to this study, the sponge fauna of Martinique is currently represented by a minimum of 191 species, 134 of which we could assign species names. One third of the remaining non-identified sponge species we consider to be new to science. Martinique appears very remarkable because of its littoral marine fauna harboring sponge aggregations with high biomass and species diversity dominating over coral species. In mangroves, sponges cover about 10% of the surface of subtidal roots. Several submarine caves are true reservoirs of hidden and insufficiently described sponge diversity. Thanks to this new collaborative effort, the Eastern Caribbean has gained a significant increase of knowledge, with sponge diversity of this area potentially representing 40% of the total in the Caribbean Sea. We thus demonstrated the importance of developing exploratory and educational research in areas historically devoid of biodiversity inventories and systematics studies. Finally, we believe in the necessity to consider not only the number of species but their distribution in space to evaluate their putative contribution to ecosystem services and our willingness to preserve them.

Sponges of the Guyana Shelf.

Sponges collected on the Guyana Shelf, predominantly in Suriname offshore waters, by Dutch HMS 'Snellius' O.C.P.S. 1966, HMS 'Luymes' O.C.P.S. II 1969, and HMS 'Luymes' Guyana Shelf 1970 expeditions are described in this study. Sponges were obtained by trawling, dredging or grabbing on sandy, muddy, shelly, and fossil reef bottoms at 88 stations between 19 and 681 m depth. A total of 351 samples were identified to species level, each consisting of one or more specimens of a given species from each individual station (together comprising 547 individuals and fragments). The collection yielded 119 species together belonging to all sponge classes, but in large majority are Demospongiae. All species are identified to species level, occasionally tentatively, and all are described and illustrated. A new subgenus is proposed, Tedania (Stylotedania) subgen. nov. and a previously synonymized genus, Tylosigma Topsent, 1894 is revived. Thirtysix species were found to be new to science, excluding the first Central West Atlantic record of the genus Halicnemia, not named at the species level because of lack of sufficient material. The new species erected are, in alphabetical order: Amphoriscus ancora sp. nov., Biemna rhabdotylostylota sp. nov., Callyspongia (Callyspongia) scutica sp. nov., Chelonaplysilla americana sp. nov., Cladocroce guyanensis sp. nov., Clathria (Axosuberites) riosae sp. nov., Clathria (Clathria) gomezae sp. nov., Clathria (Microciona) snelliusae sp. nov., Clathria (Thalysias) complanata sp. nov., Clathria (Thalysias) zeai sp. nov., Coelosphaera (Coelosphaera) lissodendoryxoides sp. nov., Craniella crustocorticata sp. nov., Diplastrella spirastrelloides sp. nov., Epipolasis tubulata sp. nov., Erylus rhabdocoronatus sp. nov., Erylus surinamensis sp. nov., Geodia pocillum sp. nov., Geodia sulcata sp. nov., Hemiasterella camelus sp. nov., Hymedesmia (Stylopus) alcoladoi sp. nov., Hymenancora cristoboi sp. nov., Penares sineastra sp. nov., Hymerhabdia kobluki sp. nov., Leucosolenia salpinx sp. nov., Petrosia (Strongylophora) devoogdae sp. nov., Placospongia ruetzleri sp. nov., Pyloderma tropicale sp. nov., Raspailia (Parasyringella) thamnopilosa sp. nov., Raspailia (Raspailia) johnhooperi sp. nov., Sphaerotylus bouryesnaultae sp. nov., Spirastrella erylicola sp. nov., Stelletta vervoorti sp. nov., Suberites crispolobatus sp. nov., Tedania (Stylotedania) folium subgen. nov. sp. nov., Timea tylasterina sp. nov., and Tylosigma ostreicola sp. nov. Two new combinations are proposed: Amphimedon nanaspiculata (Hartman, 1955) comb. nov. and Oceanapia ascidia (Schmidt, 1870) comb. nov. In addition, for two preoccupied combinations, new names, Coelosphaera (Coelosphaera) barbadensis nom. nov. and Hymedesmia (Hymedesmia) rowi nom. nov., are erected. The spatial distribution of the collected specimens over the Guyana Shelf was traced and the results were compared with existing information on bottom conditions. There was a convincing correlation between the location of fossil reefs and other hard substrates such as shell ridges with peaks in the occurrence of species diversity and specimen numbers. Stations made on sand and mud bottoms away from these zones of hard substrates were generally poor in species, but some were found to be rich in individuals of specialized soft bottom dwellers such as Tetilla pentatriaena, Tribrachium schmidtii, Fangophilina submersa, and Oceanapia species. The species composition of the Guyana Shelf was compared with that of neighbouring regions of the Caribbean and from North and East Brazil (Díaz in Miloslavich et al. 2010; Muricy et al. 2011). About 35% of the species encountered are widespread in the Central West Atlantic, occurring both to the north and to the south. Indications that the Guyana Shelf sponge fauna is clearly transitional are southernmost occurrences for Caribbean species (about 30%), and northernmost occurrences of Brazilian species (13%), with a high proportion (25%) of new species, which may be expected to have distributions extending to the Caribbean, to Brazil or both regions.

Cytotoxic Compounds Derived from Marine Sponges. A Review (2010-2012).

Abstract: This extensive review covers research published between 2010 and 2012 regarding new compounds derived from marine sponges, including 62 species from 60 genera belonging to 33 families and 13 orders of the Demospongia class (Porifera). The emphasis is on the cytotoxic activity that bioactive metabolites from sponges may have on cancer cell lines. At least 197 novel chemical structures from 337 compounds isolated have been found to support this work. Details on the source and taxonomy of the sponges, their geographical occurrence, and a range of chemical structures are presented. The compounds discovered from the reviewed marine sponges fall into mainly four chemical classes: terpenoids (41.9%), alkaloids (26.2%), macrolides (8.9%) and peptides (6.3%) which, along with polyketides, sterols, and others show a range of biological activities. The key sponge orders studied in the reviewed research were Dictyoceratida, Haplosclerida, Tetractinellida, Poecilosclerida, and Agelasida. Petrosia, Haliclona (Haplosclerida), Rhabdastrella (Tetractinellida), Coscinoderma and Hyppospongia (Dictyioceratida), were found to be the most promising genera because of their capacity for producing new bioactive compounds. Several of the new compounds and their synthetic analogues have shown in vitro cytotoxic and pro-apoptotic activities against various tumor/cancer cell lines, and some of them will undergo further in vivo evaluation.

Analysis of bacterial composition in marine sponges reveals the influence of host phylogeny and environment.

Bacterial communities associated with sponges are influenced by environmental factors; however, some degree of genetic influence of the host on the microbiome is also expected. In this work, 16S rRNA gene amplicon sequencing revealed diverse bacterial phylotypes based on the phylogenies of three tropical sponges (Aplysina fulva, Aiolochroia crassa and Chondrosia collectrix). Despite their sympatric occurrence, the studied sponges presented different bacterial compositions that differed from those observed in seawater. However, lower dissimilarities in bacterial communities were observed within sponges from the same phylogenetic group. The relationships between operational taxonomic units (OTUs) recovered from the sponges and database sequences revealed associations among sequences from unrelated sponge species and sequences retrieved from diverse environmental samples. In addition, one Proteobacteria OTU retrieved from A. fulva was identical to sequences previously reported from A. fulva specimens collected along the Brazilian coast. Based on these results, we conclude that bacterial communities associated with marine sponges are shaped by host identity, while environmental conditions seem to be less important in shaping symbiont communities. This is the first study to assess bacterial communities associated with marine sponges in the remote St. Peter and St. Paul Archipelago using amplicon sequencing of the 16S rRNA gene.

Checklist das esponjas do Estado do Mato Grosso do Sul, Brasil / Checklist of Porifera from Mato Grosso do Sul State, Brazil

The phylum Porifera, represented in the state of Mato Grosso do Sul (MS) solely by freshwater sponges, counts worldwide with around 230 species in freshwater habitats, of which 53 are presently known for Brazil and 11 for the MS. Remarkable is the fossil deposits of spicules (spongillites) produced by 6 species of these sponges in lentic quaternary freshwater habitats throughout the State and as such an important mineral resource. A new record is now produced for Mato Grosso do Sul, that of Sterrastrolepis brasiliensis. The Pantanal, Cerrado, Mata Atlântica and Chaco Biomes have not up to now been surveyed for this aquatic fauna in the State. Priority should be focused into the Pantanal, presently considered one of the world most endangered biomes.(AU)

O filo Porifera, representado no Estado do Mato Grosso do Sul somente por esponjas de água doce, conta atualmente a nível mundial com cerca de 230 espécies em ambientes dulcícolas, das quais 53 são conhecidas para o Brasil e 11 para o Estado. Destacam-se os depósitos fósseis de espículas (espongilitos) produzidos por 6 espécies dessas esponjas em ambientes lênticos quaternários de água doce em todo Estado, representando um importante recurso mineral. Um registro novo é aqui produzido para o Mato Grosso do Sul, o de Sterrastrolepis brasiliensis. Os Biomas Pantanal, Cerrado, Chaco e Mata Atlântica não foram até agora levantados para essa fauna aquática no Estado. Nesse sentido deve ser concedida prioridade ao Pantanal, considerado atualmente dos biomas mais ameaçados do planeta.(AU)

Checklist das esponjas do Estado do Mato Grosso do Sul, Brasil / Checklist of Porifera from Mato Grosso do Sul State, Brazil

The phylum Porifera, represented in the state of Mato Grosso do Sul (MS) solely by freshwater sponges, counts worldwide with around 230 species in freshwater habitats, of which 53 are presently known for Brazil and 11 for the MS. Remarkable is the fossil deposits of spicules (spongillites) produced by 6 species of these sponges in lentic quaternary freshwater habitats throughout the State and as such an important mineral resource. A new record is now produced for Mato Grosso do Sul, that of Sterrastrolepis brasiliensis. The Pantanal, Cerrado, Mata Atlântica and Chaco Biomes have not up to now been surveyed for this aquatic fauna in the State. Priority should be focused into the Pantanal, presently considered one of the world most endangered biomes.

O filo Porifera, representado no Estado do Mato Grosso do Sul somente por esponjas de água doce, conta atualmente a nível mundial com cerca de 230 espécies em ambientes dulcícolas, das quais 53 são conhecidas para o Brasil e 11 para o Estado. Destacam-se os depósitos fósseis de espículas (espongilitos) produzidos por 6 espécies dessas esponjas em ambientes lênticos quaternários de água doce em todo Estado, representando um importante recurso mineral. Um registro novo é aqui produzido para o Mato Grosso do Sul, o de Sterrastrolepis brasiliensis. Os Biomas Pantanal, Cerrado, Chaco e Mata Atlântica não foram até agora levantados para essa fauna aquática no Estado. Nesse sentido deve ser concedida prioridade ao Pantanal, considerado atualmente dos biomas mais ameaçados do planeta.

Integrative taxonomic re-description of Halisarca magellanica and description of a new species of Halisarca (Porifera, Demospongiae) from Chilean Patagonia.

A series of recent expeditions in fjords and canals of Southern Chilean Patagonia allowed the re-collection of Halisarca magellanica Topsent, 1901 and the discovery of a new species, Halisarca desqueyrouxae sp. nov. The material studied was collected at depths ranging from 3 to 30 m at latitudes comprised between 42° and 49°S. Both species share the same habitat and show a morphological plasticity, but differ in their colour. Halisarca magellanica is bright pink to whitish with three morphs whereas H. desqueyrouxae sp. nov. is light brown to beige with two morphs. An extensive investigation in TEM and SEM reveals several differences among cell types with inclusions between both species. Three distinct spherulous cells occur. Type 1 is shared by both species, Type 2 is occasional in H. magellanica but absent from H. desqueyrouxae sp. nov. Type 3 is rare in H. magellanica and occurs abundantly in half of the specimens of H. desqueyrouxae sp. nov. Granular cells are shared by both species but do not occur in all specimens. Microgranular cells are characteristic of H. magellanica. Both species also clearly differ by their endobiotic bacteria. Phylogenetic analysis of cox1 sequences places H. magellanica as a sister group to all other previously published Halisarca species sequences (9.1-9.7% difference) except H. harmelini, while H. desqueyrouxae sp. nov. is placed as a sister group to H. dujardini (2.3% difference).

A new shallow water species of Artemisina Vosmaer, 1885 (Microcionidae, Demospongiae; Porifera) from Northeastern Brazil.

Artemisina is a microcionid characterized by lacking a distinctive choanosomal skeleton or definite spongin fibres, lacking also echinating spicules, and with a nearly radial ectosomal skeleton (Hooper 2002). The genus currently has 19 valid species, six of which are recorded from the Atlantic Ocean (Van Soest et al. 2016): A. erecta Topsent, 1904, A. incrustans van Soest et al., 2013, A. melana van Soest, 1984, A. melanoides van Soest et al., 2013, A. transiens Topsent, 1890 and A. vulcani Lévi, 1963. The present study describes a new species of Artemisina from Northeastern Brazil. Four specimens of Artemisina brasili sp. nov. were collected by snorkelling at Pernambuco State. All specimens were preserved in 80% ethanol and deposited in the Porifera Collections at the Universidade Federal de Pernambuco (UFPEPOR) and Museu Nacional of Universidade Federal do Rio de Janeiro (MNRJ).

Thorectinae (Porifera: Demospongiae: Dictyoceratida) from Northeastern Brazil: two new species and transfer of Scalarispongia cincta (Boury-Esnault, 1973) to the genus Thorecta Lendenfeld, 1888.

The genus Scalarispongia was raised to gather species formerly allocated in Cacospongia with rectangular fibrous skeleton of cored primary fibers and uncored secondary fibers. Species of the genus Thorecta have a similar skeletal architecture, but the presence of a dermal armour distinguishes them from Scalarispongia. Here we describe two new species of Scalarispongia from northeastern Brazil and transfer Scalarispongia cincta to Thorecta cincta. Scalarispongia tubulata sp. nov. is thick encrusting to cushion-shaped, has tubular projections with thin walls, and surface irregularly microconulose. Scalarispongia cooki sp. nov. is massive lobate, with digitiform projections and irregular surface. Thorecta cincta n. comb. is pear-shaped with conulose surface, one large apical oscule and a belt of small oscula around the body. Its skeleton is composed by a regular and granular dermal armour and by a ladder-like network of concentrically laminated primary and secondary fibers. Cacospongia amorpha and Cacospongia levis are now the only species of the genus Cacospongia known to occur in the Brazillian coast, but both records need to be reassessed. A key to species of Thorectinae from the Tropical Western Atlantic is provided.

Cliona acephala (Porifera: Demospongiae: Clionaida), a new encrusting excavating reef sponge from the Colombian Caribbean belonging to the Cliona viridis species complex.

Several groups of sponges are able to excavate galleries and tunnels in calcareous substrata such as limestone rock, shells, calcareous algae and coral skeletons. Within the genus Cliona, some species share the common traits of being brown to olive-green in color, and harboring photosynthetic, unicellular dinoflagellates (zooxanthellae). These Cliona spp. have been grouped as the Cliona viridis species complex. Several species of this complex completely encrust the excavated substratum with a thin veneer of tissue and, when colonizing dead exposed parts of live coral colonies, they are able to undermine or overgrow and thus kill live coral tissue as they advance predominantly laterally. In the course of our taxonomic and ecological studies of Caribbean brown to brown-black encrusting Cliona, we found an as yet undescribed species that stands out by having tylostyle megasclere spicules with narrow heads and lacking the usual microsclere spicule complement of spirasters. This species, named and described here Cliona acephala n. sp., has so far been found exclusively in the Santa Marta area, Caribbean coast of Colombia. Previous studies with ITS2 ribosomal DNA showed it to be genetically distinct from other Caribbean encrusting species belonging to the Cliona viridis species complex, vis. Cliona aprica, Cliona caribbaea, Cliona tenuis and Cliona varians, but making it genetically closer to Indo-Pacific Cliona orientalis. An intriguing possibility, to be addressed with further studies, is that C. acephala n. sp. may have been introduced to the Caribbean. However, until proved otherwise, we regard the material presently described as distinct.

New Genus and species of Heteroxyidae from Brazil (Axinellida: Demospongiae: Porifera), with a revised identification key for the family.

Alveospongia sinuosclera gen. nov. sp. nov. is described from shallow-waters off Canavieiras (Bahia, Brazil). The species bears an unusual morphology, combining saccular or alveolar, evenly perforated habit, and sinuous spiny microrhabdose microscleres. This sponge is tentatively classified within the Heteroxyidae Dendy (1905), on the basis of its confused choanosomal architecture of styles, and possession of spiny microrhabdose microscleres. Assays to generate DNA sequences from this material were unsuccessful. We emended the diagnosis of the family to include species bearing saccular/alveolar shape, microrhabdose acanthomicrostrongyles and styles/strongyles with modifications at the ends. The proposed new genus is compared to the remaining heteroxyid genera, as well as Crella (Crellidae), Batzella (Chondropsidae), Goreauiella (Astroscleridae) and Sceptrintus (Podospongiidae). A revised key for identification of Heteroxyidae genera is provided.

Nicola gen. nov. with redescription of Nicola tetela (Borojevic & Peixinho, 1976) (Porifera: Calcarea: Calcinea: Clathrinida).

Guancha tetela was originally described as a species having a peduncle and a skeleton exclusively composed of sagittal triactines. Therefore, according to the most recent phylogeny of Clathrinida, it should be placed in the genus Clathrina. This species was collected on the Northeastern Brazilian coast in 1968 and it was not collected again until 2011 in Curaçao. In this study, we reanalyzed the type material and the new specimens from Curaçao under a morphological-molecular approach. Morphological analysis revealed the presence of tetractines in the skeleton of all the studied specimens, including a slide of the holotype. In the molecular phylogeny G. tetela grouped with genera containing tetractines, but as an independent new lineage, different from all the other genera of Clathrinida. Based on these results, we propose the erection of a new genus, Nicola gen. nov., to include species whose body is composed of tubes without anastomosis nor branches but that run in parallel and coalesce at the apical and basal regions. Moreover, the skeleton is exclusively composed of sagittal triactines and tetractines.

Neopetrosia de Laubenfels, 1949 from Brazil: description of a new species and a review of records (Haplosclerida: Demospongiae: Porifera).

The genus Neopetrosia was characterized by has fine brushes of oxeas issued from subectosomal tracts and compact choanosomal network. We report and describe here specimens collected in the coast of Brazil: Neopetrosia sulcata sp. nov. and Neopetrosia proxima. The first was previously recorded from Brazil as Neopetrosia proxima, but it was found that these specimens corresponded to a new species. Thus, we provide here the characterization of N. proxima from Brazilian coast. A taxonomic study of Brazilian samples is given, including description, illustrations and geographic distribution, combined with the comparison of the new species with all other descriptions of Neopetrosia from Atlantic.

Taxonomy of the Caribbean sponge Dragmacidon reticulatum (Ridley & Dendy, 1886) (Porifera, Demospongiae, Axinellida), with the description of a new species.

Although there is a long history of taxonomic investigation in Caribbean sponges, there are still many undescribed species. Furthermore, field observations and corroborating morphological analyses are revealing that what was believed to be single, somewhat variable species, may consist of two or more species, often easier to distinguish once well characterized. This is the case for Dragmacidon reticulatum (Ridley & Dendy, 1886) (Porifera, Demospongiae, Axinellida, Axinellidae), a rather well-known sponge, with an ample distribution and presence in rocky and reef environments of the tropical and subtropical Western Atlantic, with local records in the majority of the countries of the area, from Bermuda to Brazil. Field observations and a detailed review of material from different areas, including some type specimens, led us to the distinction of two different species in terms of external morphology, size of spicules, and skeletal architecture. The distinction was confirmed in the Bahamas and Santa Marta, Colombia, where the two species coexist. One of the species is Dragmacidon reticulatum sensu stricto, but for the other there is need to erect a new name, for which we propose Dragmacidon alvarezae n. sp. The purpose of the present work is to describe, illustrate and compare these two species.

Lissodendoryx (Ectyodoryx) Lundbeck, 1909 (Coelosphaeridae, Poecilosclerida, Demospongiae) from Southern Chile: new species and a discussion of morphologic characters in the subgenus.

Our ongoing studies of the Chilean sponge fauna revealed four new species of Lissodendoryx (Ectyodoryx) that are described here, including three from the fjord's region (< 30 m depth, L.(E.) ballena sp. nov., L. (E.) corrugata sp. nov.,      L. (E.) coloanensis sp. nov.), and one from the deep waters off Diego Ramírez Archipelago (ca. 2000 m, L. (E.) diegoramirezensis sp. nov.). In addition, the type of L. (E.) anacantha was revised and found to bear much larger acanthostyles than originally reported. Our results revealed skeletal architectures quite distinct from that reported from the type species of L. (Ectyodoryx), and not predicted in the current diagnosis of Lissodendoryx, requiring an amended diagnosis. Ectosomal megascleres also set the majority of the new species apart from the type species of L. (Ectyodoryx), which does not have terminally microspined (sub)tylotes. This character is widespread in Lissodendoryx and might be pointing to phylogenetic affinities across the current subgeneric arrangement. Further morphologic characters and alternative phylogenetic scenarios are discussed, including hymedesmiid and myxillid affinities of the species described here.

Investigation of freshwater sponges spicules deposits in a karstic lake in Brazil.

The environmental conditions which contributed to the formation of the notorious quaternary deposits of freshwater sponge spicules in karstic lentic environments in Brazil have been subject of some speculation. No investigation has yet been conducted to test whether these deposits currently originate in karstic lakes. To provide for such an investigation, Serra Negra Lake, which is formed on an ultramafic-alkaline-carbonatite dome at central western Brazil, close to the area of occurrence of the paleo-deposits was selected for the study. Bottom sediments were sampled at 10 stations across the lake, and water was sampled at five of the stations, in June/2011 (rainy season) and October/2011 (dry season). Analysis of granulometry, organic matter and presence of spicules were carried out in the sediments. Lake water was analysed for the main physical and chemical characteristics. Deposit of spicules was restricted to the northern area of the lake, which is rich in macrophyte. The taxonomic analysis of the spicules indicated the contribution of five sponge species, Dosilia pydanieli, Metania spinata, Radiospongilla amazonensis, Trochospongilla variabilis and Heterorotula fistula, which formed large deposits in neighbouring areas. The high silica concentration, derived from the dome volcanic rocks, constant water level and available substrate are credited for the continuous production of sponges and spicules, confirmed by the rare presence of gemmoscleres. The lake is classed as a minerotrophic fen type of bog with a heavy contribution from the surrounding creeks. Lake sediments are fine with high levels of organic matter and peat, which contributed to the trapping of spicules in the sediments.

Investigation of freshwater sponges spicules deposits in a karstic lake in Brazil / Investigação de depósito de espículas de esponjas de água doce em um lago cárstico no Brasil

Abstract The environmental conditions which contributed to the formation of the notorious quaternary deposits of freshwater sponge spicules in karstic lentic environments in Brazil have been subject of some speculation. No investigation has yet been conducted to test whether these deposits currently originate in karstic lakes. To provide for such an investigation, Serra Negra Lake, which is formed on an ultramafic-alkaline-carbonatite dome at central western Brazil, close to the area of occurrence of the paleo-deposits was selected for the study. Bottom sediments were sampled at 10 stations across the lake, and water was sampled at five of the stations, in June/2011 (rainy season) and October/2011 (dry season). Analysis of granulometry, organic matter and presence of spicules were carried out in the sediments. Lake water was analysed for the main physical and chemical characteristics. Deposit of spicules was restricted to the northern area of the lake, which is rich in macrophyte. The taxonomic analysis of the spicules indicated the contribution of five sponge species, Dosilia pydanieli, Metania spinata, Radiospongilla amazonensis, Trochospongilla variabilis and Heterorotula fistula, which formed large deposits in neighbouring areas. The high silica concentration, derived from the dome volcanic rocks, constant water level and available substrate are credited for the continuous production of sponges and spicules, confirmed by the rare presence of gemmoscleres. The lake is classed as a minerotrophic fen type of bog with a heavy contribution from the surrounding creeks. Lake sediments are fine with high levels of organic matter and peat, which contributed to the trapping of spicules in the sediments.

Resumo As condições ambientais que contribuíram para a formação de notórios depósitos quaternários de espículas de esponjas de água doce em ambientes cársticos no Brasil têm sido objeto de algumas especulações. Nenhuma investigação foi ainda realizada para testar se esses depósitos originam-se atualmente em lagos cársticos. Para prover tal investigação, a Lagoa Serra Negra, formada em um domo ultramáfico-alcalino-carbonatítico, no centro oeste do Brasil, próximo à área de ocorrência dos referidos paleo-depósitos, foi selecionada para o estudo. Sedimentos de fundo foram amostrados em 10 estações ao longo do lago, e a água foi coletada em cinco das estações, em junho/2011 (estação chuvosa) e outubro/2011 (estação seca). Análises de granulometria, matéria orgânica e presença de espículas foram realizadas nos sedimentos. A água do lago foi analisada para as principais características físicas e químicas. O depósito de espículas foi restrito à área norte do lago, que é rico em macrófitas. A análise taxonômica das espículas indicou a contribuição de cinco espécies de esponjas, Dosilia pydanieli, Metania spinata, Radiospongilla amazonensis, Trochospongilla variabilis e Heterorotula fistula, que formaram grandes depósitos em áreas vizinhas. A alta concentração de sílica, derivada das rochas vulcânicas do domo, o nível constante da água e a disponibilidade de substrato são creditadas à produção contínua de esponjas e espículas, confirmada pela presença rara de gemoscleras. O lago é classificado como uma turfeira do tipo fen, minerotrófica, com forte contribuição dos arroios circundantes. Os sedimentos da lagoa são finos, com altos níveis de matéria orgânica e formação de turfa, o que contribuiu para a captura das espículas nos sedimentos.

Five new species of Jaspis (Porifera: Demospongiae: Tetractinellida:Astrophorina) from Brazil with redescription of the type species Jaspis johnstonii (Schmidt, 1862).

The genus Jaspis comprises 32 valid species, six of which were previously recorded from the Atlantic Ocean. Two species have already been recorded from the Brazilian coast: J. johnstonii and J. salvadori (Rio Grande do Sul and Espírito Santo States respectively). Their respective type specimens, deposited at Muséum National d'Historie Naturelle, Paris (Jaspis salvadori, holotype) and at Universalmuseum Joanneum, Zoology Center of Natural History, Austria (Jaspis johnstonii, syntype) were reexamined, but due to differences in spicule composition these records are considered to be invalid. The present paper describes five new species of Jaspis collected on the Brazilian coast (Jaspis atolensis sp. nov., J. iacuitaster sp. nov., J. corticomicroxea sp. nov., J. variaster sp. nov. and J. gigoxea sp. nov.) bringing the total number of species worldwide to 36, all of which were compared in tabular format. The type species, Jaspis johnstonii, was also redescribed.

Two new species of Timea from the Southwest Atlantic (Timeidae, Demospongiae, Porifera).

Comprising 56 species, Timea Gray, 1867 belongs to the monotypic family Timeidae Gray, 1867, with both family and genus characterized by the presence of (sub)tylostyles as megascleres, and euasters as microscleres. Two new species are described from the coast of Rio de Janeiro state, Timea berlincki sp. nov. and Timea clandestina sp. nov., the first of which also from São Paulo state (southeastern Brazil). Both are compared to other species based on their morphological and skeletal characters. Records of all species of the genus worldwide are tabulated and discussed, and an identification key for Tropical western Atlantic species of Timea is offered.