Papers by Guilherme Ramos da Silva Muricy
Manned submersible dives reveal a singular assemblage of Hexactinellida (Porifera) off the Amazon River mouth, Northern Brazil
Zootaxa, 2022
The outer shelf and upper slope region under the influence of the Amazon River mouth harbors an e... more The outer shelf and upper slope region under the influence of the Amazon River mouth harbors an extensive reef system with a rich sponge fauna, but no hexactinellids were recorded in the area so far. In this work, manned submersibles were used to describe for the first time three species of Hexactinellida off the Amazon River mouth: Hyalonema (Cyliconemaoida) alucia sp. nov., Dactylocalyx pumiceus and Claviscopulia facunda. We found two morphotypes of Dactylocalyx pumiceus, suggesting that it may be a complex of cryptic species. The populations of the three species off Pará State were sparse, but a large aggregation of D. pumiceus was found off Maranhão State from 145 to 230 m depth. These findings indicate that hexactinellid grounds may be more common along the Northern Brazilian continental outer shelf and slope than previously thought.
Zoological Journal of the Linnean Society, 2017
Among the Porifera, the taxonomy and systematics of Homoscleromorpha is one of the most challengi... more Among the Porifera, the taxonomy and systematics of Homoscleromorpha is one of the most challenging. Over the last two decades, this class and its single order Homosclerophorida have seen a high rate of new descriptions and phylogenetic investigations which have led to the resurrection of two well-supported families, defined as the `spiculate' Plakinidae and the `aspiculate' Oscarellidae. In recent years, the development of an integrative taxonomic approach and the exploration of new marine ecosystems have revealed an even higher diversity of Homoscleromorpha and highlighted the importance of complementary datasets (cytological, biochemical and molecular) to better explain the phylogenetic classification. Using this integrative approach, we here describe two new species of Plakinidae from submarine caves in the Caribbean Sea: Plakina arletensis sp. nov. and Aspiculophora madinina gen. nov. sp. nov., the latter being aspiculate with an unusually well-developed collagen layer ...
Diversity of Homoscleromorpha (Porifera) in two submarine caves in the Aegean Sea (eastern Mediterranean)
Sponges of the class Homoscleromorpha are hard substratum dwellers, often found in dark or semida... more Sponges of the class Homoscleromorpha are hard substratum dwellers, often found in dark or semidark habitats. During a research on cave sponge diversity in the north Aegean Sea, we surveyed with SCUBA diving two submarine caves in Lesvos Island (Aegean Sea, eastern Mediterranean): Fara Cave (18 m depth) and Agios Vasilios Cave (23-40 m depth). Among the collected material, we identified 10 homoscleromorph species, which we present in this study. Four of them were identified as species of the genus Oscarella (family Oscarellidae): O. cf. balibaloi, O. cf. tuberculata, O. cf. microlobata, and O. jarrei ) and six were species of Plakina (family Plakinidae): P. trilopha, P. bowerbanki, P. cf. crypta, P. aff. weinbergi, and Plakina spp. nov. 1–2. Some of these species have been rarely reported in the Mediterranean up to date: O. microlobata and P. weinbergi were sporadically recorded in a small number of caves in the Mediterranean Sea, while P. crypta was found in a single cave in the no...
Genomic and in silico protein structural analyses provide insights into marine polysaccharide-degrading enzymes in the sponge-derived Pseudoalteromonas sp. PA2MD11
International Journal of Biological Macromolecules, 2021
Active heterotrophic metabolism is a critical metabolic role performed by sponge-associated micro... more Active heterotrophic metabolism is a critical metabolic role performed by sponge-associated microorganisms, but little is known about their capacity to metabolize marine polysaccharides (MP). Here, we investigated the genome of the sponge-derived Pseudoalteromonas sp. strain PA2MD11 focusing on its macroalgal carbohydrate-degrading potential. Carbohydrate-active enzymes (CAZymes) for the depolymerization of agar and alginate were found in PA2MD11's genome, including glycoside hydrolases (GHs) and polysaccharide lyases (PLs) belonging to families GH16, GH50 and GH117, and PL6 and PL17, respectively. A gene potentially encoding a sulfatase was also identified, which may play a role in the strain's ability to consume carrageenans. The complete metabolism of agar and alginate by PA2MD11 could also be predicted and was consistent with the results obtained in physiological assays. Despite the polysaccharide utilization locus (PUL) potentially involved in the metabolism of agarose contained mobile genetic elements from other marine Gammaproteobacteria, its unusual larger size might be due to gene duplication events. Homology modelling and structural protein analyses of the agarases, alginate lyases and sulfatase depicted clear conservation of catalytic machinery and protein folding together with suitable industrially-relevant features. Pseudoalteromonas sp. PA2MD11 is therefore a source of potential MP-degrading biocatalysts for biorefinery applications and in the preparation of pharmacologically-active oligosaccharides.
Taxonomy of Plakina (Porifera: Homoscleromorpha) from Aegean submarine caves, with descriptions of three new species and new characters for the genus
Marine Biodiversity, 2018
Sponges of the Class Homoscleromorpha, despite their high evolutionary significance, are still po... more Sponges of the Class Homoscleromorpha, despite their high evolutionary significance, are still poorly known due to their small size and cryptic habit. In this study, we describe five species of the homoscleromorph genus Plakina from submarine caves in the Aegean Sea (Lesvos Island, Greece): Plakina bowerbanki, P. trilopha, P. anisoactina sp. nov., P. anomala sp. nov., and P. hellenica sp. nov. Plakina anomala sp. nov. is the first species of the genus with papillae and the first Homoscleromorpha with a microcavity-filling habit. Plakina bowerbanki, P. anomala sp. nov. and P. anisoactina sp. nov. present exceptionally stout, annulated lophose spicules with highly variable ramification patterns, including some original types. The high diversity of Plakina in the two caves of Lesvos Island is similar to that of northwestern Mediterranean caves. Despite being much less studied, the Aegean Sea now equals the Western Mediterranean as the two ecoregions of the Mediterranean with the highest diversity of Plakina, with eight species each. The Aegean Sea encompasses a huge number of submarine caves, and therefore it has great potential for the discovery of new species of Homoscleromorpha.
Taxonomy and phylogeny of calcareous sponges (Porifera: Calcarea: Calcinea) from Brazilian mid-shelf and oceanic islands
Zootaxa, 2017
Despite the enormous economic, scientific and strategic value of the Brazilian oceanic and mid-sh... more Despite the enormous economic, scientific and strategic value of the Brazilian oceanic and mid-shelf islands (BOMIs), the biological communities of these islands are still poorly known. An example is their fauna of calcareous sponges (Porifera: Calcarea), with only six species described up to date. In the present study, we analysed the Calcinean sponges from the mid-shelf Abrolhos Archipelago and four of the five Brazilian oceanic islands (São Pedro e São Paulo Archipelago, Fernando de Noronha Archipelago, Rocas Atoll, and Trindade Island), using both morphological and molecular approaches for taxonomy. Fourteen species were found, of which 12 are new to science: Arturia trindadensis sp. nov., Borojevia tenuispinata sp. nov., B. trispinata sp. nov., Clathrina insularis sp. nov., C. lutea sp. nov., C. mutabilis sp. nov., C. zelinhae sp. nov., Ernstia citrea sp. nov., E. multispiculata sp. nov., E. rocasensis sp. nov., E. sanctipauli sp. nov., and E. solaris sp. nov. These results rai...
Zootaxa, 2005
Stelletta anasteria sp. nov., a new species of Stelletta without microscleres from Abrolhos archi... more Stelletta anasteria sp. nov., a new species of Stelletta without microscleres from Abrolhos archipelago, northeastern Brazil, is described. The new species is best classified in Stelletta due to its growth habit, the shape of its triaenes and oxeas, presence of a cortex and a disorganized choanosomal skeleton. Besides the absence of microscleres, that set it apart from all other species of the genus, it differs from all other tropical Atlantic species of Stelletta in presenting at the same time all megascleres smaller than 590 µm long, the clads of plagiotriaenes smaller than 70 µm long, and those of anatriaenes smaller than 20 µm long. Additionally, anatriaenes with ill-formed and/or additional clads along the rhabdome are common in the new species.
Brazilian Journal of Microbiology, 2016
b r a z i l i a n j o u r n a l o f m i c r o b i o l o g y 4 7 (2 0 1 6) 617-620 h t t p : / / w... more b r a z i l i a n j o u r n a l o f m i c r o b i o l o g y 4 7 (2 0 1 6) 617-620 h t t p : / / w w w . b j m i c r o b i o l . c o m . b r /
Zoological Journal of the Linnean Society, 1998
Taxonomy and distribution of Bugula (Bryozoa: Cheilostomata
Proceedings of the 13th International Bryozoology Association conference, Concepción/Chile, 11-16 January 2004, 2005
A new species of Cinachyra (Demospongiae: Tetillidae) collected by Project REVIZEE off Espírito Santo State, SE Brazil
A new species of Cinachyra Sollas (Porifera, Spirophorida) was dredged from 500 m depth off Espir... more A new species of Cinachyra Sollas (Porifera, Spirophorida) was dredged from 500 m depth off Espirito Santo State, SE Brazil, by Project REVIZEE Central SCORE. Cinachyra helena sp. nov. is characterized by the presence of a single category each, of protriaenes, anatriaenes, anisoactinal choanosomal oxeas, isoactinal cortical oxeas, and sigmaspires. The cortex is formed by small isoactinal oxeas arranged obliquely to the surface, and an anchoring basal spicule mass is absent. This is the first valid record of Cinachyra from the Atlantic; all similar species lacking a cortex should be transferred to Cinachyrella or other genera of Tetillidae. At the present state of knowledge, there are four valid species in the genus Cinachyra: C. barbata Sollas, C. crustata (Wilson), C. uteoides Dendy, and C. helena sp. nov.
A new species of Gastrophanella from central western Atlantic, with a discussion of the family Siphonidiidae (Demospongiae: Lithistida)
Journal of the Marine Biological Association of the United Kingdom, 2000
A new species of Gastrophanella, G. cavernicola sp. nov. (Demospongiae: Siphonidiidae), is descri... more A new species of Gastrophanella, G. cavernicola sp. nov. (Demospongiae: Siphonidiidae), is described from submarine caves in Fernando de Noronha Island (north-east Brazil), Carrie Bow Cay and Columbus Cay, Belize (central Western Atlantic), at depths of 5-30 m. It differs from all other species of the genus by its lobate shape with thin superficial canals and centrotylote tylostrongyles. Gastrophanella cavernicola sp. nov. is the second record of the genus Gastrophanella from both Brazil and the Caribbean. It is the sixth ‘lithistid’ sponge reported from the Brazilian coast, whereas at least 32 other desma-bearing sponges are known from the Caribbean. The genus now includes five valid species, G. implexa Schmidt from the West Indies (type species), G. mammilliformis Burton from South Africa, G. primore Gómez from the Pacific Coast of Mexico, G. stylifera Mothes & Silva from south Brazil, and G. cavernicola sp. nov. from north-east Brazil and Belize. Aciculites oxytylota Lévi & Lévi ...
Journal of Chemical Ecology, 1999
The furanosesterterpene variabilin was identified in an unpalatable crude extract and proved to b... more The furanosesterterpene variabilin was identified in an unpalatable crude extract and proved to be a feeding deterrent when offered at 0.23% of artificial diet dry weight to reef fishes in field assays. The icthyodeterrent property of variabilin was expressed when food pellets for the palatability assays were made with calcium alginate, but not carrageenan. Variabilin probably failed to show deterrent
Order Homosclerophorida Dendy, 1905, Family Plakinidae Schulze, 1880
Systema Porifera, 2002
Homosclerophorida Dendy (Demospongiae, Homoscleromorpha) contains a single family Plakinidae Schu... more Homosclerophorida Dendy (Demospongiae, Homoscleromorpha) contains a single family Plakinidae Schulze (including Oscarellidae Lendenfeld and Corticiidae Vosmaer), with seven valid genera and about 60 valid species worldwide. Species live mainly in shallow waters but a few have been recorded from abyssal depths (up to 2460m). Species are often encrusting, lobate, but massive species are common in some genera (Plakortis, Plakinastrella); surface is usually smooth or microhispid and consistency varies from soft to cartilaginous. All genera possess flagellated exo- and endopinacocytes, a basement membrane lining both choanoderm and pinacoderm, oval to spherical choanocyte chambers with a sylleibid-like or leuconoid organization, and a unique incubated cinctoblastula-type larvae; spicules, when present, are peculiar tetractines (calthrops) and derivatives. Genera are distinguished mainly by four morphological characters: presence of a siliceous skeleton; presence of a cortex associated with a leuconoid aquiferous system and well-developed mesohyl or a sylleibid aquiferous system with poorly developed mesohyl and ectosome; number of spicule size classes; and presence and type of ramifications in the actines of calthrops (tetractinal spicules), with three distinct general morphologies recognized.
Zootaxa, 2013
Seven species of Plakinidae are currently known from Brazil, belonging to genera Plakina (P. tril... more Seven species of Plakinidae are currently known from Brazil, belonging to genera Plakina (P. trilopha), Plakinastrella (P. microspiculifera, P. onkodes), and Plakortis (P. angulospiculatus, P. halichondrioides, P. insularis, and P. microrhabdifera). In this study we describe four new species of the genera Plakinastrella and Plakortis, increasing the number of plakinid species in Brazil to eleven. Plakortis petrupaulensis sp. nov. is encrusting, light brown; the skeleton is disorganized with few traces of reticulation; lacunae are absent; the spicules are diods and tuberculate microrhabds; spheres are common and triods are absent. Plakortis spinalis sp. nov. is encrusting, gray, cartilaginous, has a reticulated ectosomal skeleton, and is distinguished by the spines in some of the diods and triods; microrhabds are also tuberculate and smooth spheres are common. Plakortis potiguarensis sp. nov. is encrusting, brown with gray tinges, and cartilaginous; the skeleton is disorganized and scarce, composed of thin, irregular diods, triods and relatively large microrhabds. Plakinastrella globularis sp. nov. has a globular shape and dark blue color in vivo; the ectosomal skeleton has a double tangential reticulation and the choanosomal skeleton is reticulated. The spicules are diods, triods, calthrops and microrhabds; spheres are common. Two of the new species have characters previously unknown in their respective genera: the spined diods and triods of Plakortis spinalis sp. nov. and the blue color and microrhabds of Plakinastrella globularis sp. nov. The presence of microrhabds in Plakinastrella suggests a close relationship of this genus with Plakortis.
Three new species of Strongylacidon (Chondropsidae: Poecilosclerida: Demospongiae) from north-east Brazil, with new morphological characters for the family
Journal of the Marine Biological Association of the United Kingdom, 2011
Three new species ofStrongylacidonfrom north-east Brazil are described:Strongylacidon oxychaetums... more Three new species ofStrongylacidonfrom north-east Brazil are described:Strongylacidon oxychaetumsp. nov. andStrongylacidon solangeaesp. nov. from Bahia State, andStrongylacidon chelospinatasp. nov. from Fernando de Noronha Archipelago, Pernambuco State.Strongylacidon oxychaetumsp. nov. has thinly encrusting shape with lobate projections, strongyles, oxychaetes and arcuate chelae;S. solangeaesp. nov. is characterized by having massive shape with hispid surface, strongyles and unguiferate chelae; andS. chelospinatasp. nov. present thinly encrusting shape, strongyles, and arcuate isochelae with large spines on the outer edge of the axis. An identification key for the nine valid species ofStrongylacidonfrom the Tropical Western Atlantic is provided. New morphological characters, viz., oxychaetes and spined arcuate isochelae (here termed acanthochelae), are added to the definition of the genusStrongylacidonand of the family Chondropsidae.
Journal of the Marine Biological Association of the United Kingdom, 2004
The structure and distribution of the sponge community in five sites and four habitats in Cagarra... more The structure and distribution of the sponge community in five sites and four habitats in Cagarras Archipelago, Rio de Janeiro, Brazil, are described. The archipelago has three major islands (Cagarra, Palmas, and Comprida), and four islets. Qualitative samples were taken by SCUBA diving in the three islands and in two islets, and quantitative samples were taken in Palmas Island only. Cluster analysis using Jaccard's coefficient on qualitative data grouped the two islets (Cagarra Bank and Cagarra Islet), which are more exposed to wave action, and the three islands formed a group of relatively sheltered sites. Cluster analysis using Bray–Curtis coefficient on quantitative data from different habitats in Palmas Island allowed distinction of three groups of samples: overhangs, shallow horizontal surfaces (6 m depth), and vertical walls plus deeper horizontal surfaces (17 m depth). Sponge abundance was greater in overhangs (61·2 ind m−2), which were dominated by Protosuberites sp. an...
Diet of the queen angelfish Holacanthus ciliaris (Pomacanthidae) in São Pedro e São Paulo Archipelago, Brazil
Journal of the Marine Biological Association of the United Kingdom, 2012
Holacanthus ciliaris is an important benthic-feeding reef fish but the relationship between the c... more Holacanthus ciliaris is an important benthic-feeding reef fish but the relationship between the composition of its diet and prey availability is still unknown. Here we determined the quantitative composition of the gut contents of H. ciliaris in São Pedro e São Paulo Archipelago, Brazil (SPSPA), and compared it to the abundance of benthic organisms in the area. Holacanthus ciliaris has a relatively diversified diet with more than 30 prey species in SPSPA, especially sponges (13 spp., average 68% of gut contents total weight), algae (12 spp., 25%) and bryozoans (3 spp., 5%). In contrast, the benthic community is composed mainly of algae (average 81% of total cover) and followed by sponges (13%), bryozoans (5%), cnidarians (0.5%), polychaetes (0.5%) and tunicates (0.5%). The most common species were the algae Caulerpella ambigua and Caulerpa racemosa var. peltata; the bryozoan Margaretta buski; and the sponges Scopalina ruetzleri, Chondrosia collectrix and Clathria calla. The Manly re...
A new species of Thorecta (Porifera: Demospongiae) from the western Atlantic, with remarks on the taxonomy of the genus
Journal of the Marine Biological Association of the United Kingdom, 2010
The family Thorectidae includes 23 valid genera and 130 species, characterized by the presence of... more The family Thorectidae includes 23 valid genera and 130 species, characterized by the presence of laminated fibres and diplodal choanocytye chambers. Currently the genus Thorecta comprises approximately 20 valid species, distributed mainly in the Indo-Pacific. We describe here a new species of Thorecta that is the only valid species of the genus described in the Atlantic Ocean so far. Samples were collected by trawling on board of the RV ‘Astro Garoupa’ in Potiguar Basin, on the northern coast of Rio Grande do Norte State, north-eastern Brazil. Thorecta atlantica sp. nov. is greyish-brown to dark brownish-grey and presents a distinctive globular or clavulate shape, with 1–2 large apical oscules that open to deep atria. It was found between 61 and 160 m depth. A literature survey suggests that many species referred to Thorecta should be relocated to different genera due to absence of diagnostic characters, and that the genus Thorecta should group only 11 species: T. carteri, T. margi...
Uploads
Papers by Guilherme Ramos da Silva Muricy