I'm an Assistant Researcher and leader of the Deep-Sea Biodiversity and Conservation Team at CIIMAR, University of Porto (Portugal), and an invited Associate Professor II in Deep-Sea Biology at the Department of Biological Sciences of the University of Bergen (Norway). My research focusses in the understanding of basin- to global-scale diversity, biogeographic, and connectivity patterns of deep-sea sponges and the habitats they form (i.e. sponge grounds), using a combination of disciplines (taxonomy, systematics, ecology and genomics). I collaborate with a vast network of European and North American scientists, and have trained and mentored 15+ students (from BSc to PhD levels) in the fields of sponge taxonomy, systematics, phylogenetics, and population genomics. I coordinate the DEEPbaseline project, an awardee of the Ocean Conservation Fund; and was scientific manager and co-lead WP3 of the H2020 SponGES project, funded by the European Commission.

Vitenskapelig artikkel

• Theising, Franziska I.; Hentschel, Ute; Busch, Kathrin et al. (2025). Does an arctic circumpolar distribution exist for deep-sea sponges? Unravelling the systematics of Stylocordyla borealis (Porifera: Demospongiae) through integrative taxonomy. (ekstern lenke)
• Patova, Anna; Ribeiro, Pedro; Murillo, Francisco J. et al. (2025). Population genomics and connectivity of Vazella pourtalesii sponge grounds of the northwest Atlantic with conservation implications of deep sea vulnerable marine ecosystems. (ekstern lenke)
• Tojeira, Inês; Souto, Miguel; Kaufmann, Manfred et al. (2025). From physics to fish: 50 Years of research at Great Meteor Seamount, NE Atlantic. (ekstern lenke)
• Gregório, Inês; Xavier, Joana R.; Davies, Andrew J. (2024). Present and future distribution of the deep-sea habitat-forming sponge - Pheronema carpenteri ( Thomson, 1869) in a changing ocean. (ekstern lenke)
• Scepanski, Dominik; Augustin, Nico; Dünn, Manon et al. (2024). Vertical distribution of epibenthic megafauna of a large seamount west of Cape Verde islands (tropical North Atlantic). (ekstern lenke)
• Ramirez-Llodra, Eva; Meyer, Heidi Kristina; Bluhm, Bodil Annikki Ulla Barbro et al. (2024). The emerging picture of a diverse deep Arctic Ocean seafloor: From habitats to ecosystems. (ekstern lenke)
• Canning-Clode, João; Gizzi, Francesca; Braga-Henriques, Andreia et al. (2024). A pioneering longterm experiment on mesophotic macrofouling communities in the North Atlantic. (ekstern lenke)
• Hendry, K.R.; Pryer, H.; Bates, S.L. et al. (2024). Spicule morphology impacts stable silicon isotopic composition of sponge archives. (ekstern lenke)
• Campanyà-Llovet, Neus; Bates, Amanda E.; Cuvelier, Daphne et al. (2023). FUN Azores: a FUNctional trait database for the meio-, macro-, and megafauna from the Azores Marine Park (Mid-Atlantic Ridge). (ekstern lenke)
• Taboada, Sergi; Whiting, Connie; Wang, Shuangqiang et al. (2023). Long distance dispersal and oceanographic fronts shape the connectivity of the keystone sponge Phakellia ventilabrum in the deep northeast Atlantic. (ekstern lenke)
• Mejía-Saenz, Alejandra; Simon-Lledó, Erik; Partridge, Louis S. et al. (2023). Rock outcrops enhance abyssal benthic biodiversity. (ekstern lenke)
• Brodnicke, Ole Bjørn; Meyer, Heidi Kristina; Busch, Kathrin et al. (2023). Deep-sea sponge derived environmental DNA analysis reveals demersal fish biodiversity of a remote Arctic ecosystem. (ekstern lenke)
• Brix, Saskia; Kaiser, Stephanie; Lörz, Anne-Nina et al. (2022). Habitat variability and faunal zonation at the Aegir Ridge, a canyon-like structure in the deep Norwegian Sea. (ekstern lenke)
• Taboada, Sergi; Ríos, Pilar; Mitchell, Alex et al. (2022). Genetic diversity, gene flow and hybridization in fan-shaped sponges (Phakellia spp.) in the North-East Atlantic deep sea. (ekstern lenke)
• Busch, Kathrin; Slaby, Beate M.; Bach, Wolfgang et al. (2022). Biodiversity, environmental drivers, and sustainability of the global deep-sea sponge microbiome. (ekstern lenke)
• Meyer, Heidi Kristina; Davies, A.J.; Roberts, Emyr Martyn et al. (2022). Beyond the tip of the seamount: Distinct megabenthic communities found beyond the charismatic summit sponge ground on an arctic seamount (Schulz Bank, Arctic Mid-Ocean Ridge). (ekstern lenke)
• Denderen, P. Daniël Van; Holah, Helen; Robson, Laura M. et al. (2022). A policy-based framework for the determination of management options to protect vulnerable marine ecosystems under the EU deep-sea access regulations. (ekstern lenke)
• Santin, Andreu; Uriz, Maria-Jesus; Cristobo, Javier et al. (2021). Unique spicules may confound species differentiation: Taxonomy and biogeography of Melonanchora Carter, 1874 and two new related genera (Myxillidae: Poecilosclerida) from the Okhotsk Sea. (ekstern lenke)
• Dudik, Olesia; Amorim, Sara; Xavier, Joana R. et al. (2021). Bioactivity of Biosilica Obtained From North Atlantic Deep-Sea Sponges. (ekstern lenke)
• Figueiredo, Cátia; Caetano, Miguel; Mil-Homens, Mário et al. (2021). Rare earth and trace elements in deep-sea sponges of the North Atlantic. (ekstern lenke)
• Xavier, Joana R.; Rees, David John; Pereira, Raquel et al. (2021). Diversity, distribution and phylogenetic relationships of deep-sea lithistids (Porifera, Heteroscleromorpha) of the Azores archipelago. (ekstern lenke)
• Howell, Kerry L.; Hilário, Ana; Allcock, A. Louise et al. (2021). A decade to study deep-sea life. (ekstern lenke)
• Rooks, Christine; Fang, James Kar-Hei; Mørkved, Pål Tore et al. (2020). Deep-sea sponge grounds as nutrient sinks: Denitrification is common in boreo-Arctic sponges. (ekstern lenke)
• Martins, Eva; Rapp, Hans Tore; Xavier, Joana R. et al. (2020). Macro and Microstructural Characteristics of North Atlantic Deep-Sea Sponges as Bioinspired Models for Tissue Engineering Scaffolding. (ekstern lenke)
• Carvalho, Francisca Correia De; Cárdenas, Paco; Ríos, Pilar et al. (2020). Rock sponges (lithistid Demospongiae) of the Northeast Atlantic seamounts, with description of ten new species. (ekstern lenke)
• Ríos, Pilar; Prado, Elena; Carvalho, Francisca Correia De et al. (2020). Community Composition and Habitat Characterization of a Rock Sponge Aggregation (Porifera, Corallistidae) in the Cantabrian Sea. (ekstern lenke)
• Alvizu, Adriana; Xavier, Joana R.; Rapp, Hans Tore (2019). Description of new chiactine-bearing sponges provides insights into the higher classification of Calcaronea (Porifera: Calcarea). (ekstern lenke)
• Riesgo, Ana; Taboada, Sergi; Pérez-Portela, Rocío et al. (2019). Genetic diversity, connectivity and gene flow along the distribution of the emblematic Atlanto-Mediterranean sponge Petrosia ficiformis (Haplosclerida, Demospongiae). (ekstern lenke)
• Ramiro-Sanchez, Berta; Gonzalez-Irusta, Jose Manuel; Henry, Lea-Anne et al. (2019). Characterization and mapping of a deep-sea sponge ground on the tropic seamount (Northeast Tropical Atlantic): Implications for spatial management in the high seas. (ekstern lenke)
• Howell, Kerry L.; Davies, Jaime S.; Allcock, A. Louise et al. (2019). A framework for the development of a global standardised marine taxon reference image database (SMarTaR-ID) to support image-based analyses. (ekstern lenke)
• Hawkes, Nickolas James; Korabik, Michelle; Beazley, Lindsay et al. (2019). Glass sponge grounds on the Scotian Shelf and their associated biodiversity. (ekstern lenke)
• Beazley, Lindsay; Wang, Zeliang; Kenchington, Ellen et al. (2018). Predicted distribution of the glass sponge Vazella pourtalesi on the Scotian Shelf and its persistence in the face of climatic variability. (ekstern lenke)
• Alvizu, Adriana; Eilertsen, Mari Heggernes; Xavier, Joana R. et al. (2018). Increased taxon sampling provides new insights into the phylogeny and evolution of the subclass Calcaronea (Porifera, Calcarea). (ekstern lenke)
• Cardenas, Paco; Vacelet, Jean; Chevaldonné, Pierre et al. (2018). From marine caves to the deep sea, a new look at caminella (Demospongiae, geodiidae) in the atlanto-Mediterranean region. (ekstern lenke)
• Cassarino, Lucie; Coath, Christopher D.; Xavier, Joana R. et al. (2018). Silicon isotopes of deep sea sponges: New insights into biomineralisation and skeletal structure. (ekstern lenke)
• Dudik, Olesia; Leonor, Isabel; Xavier, Joana R. et al. (2018). Sponge-derived silica for tissue regeneration: Bioceramics of deep-sea sponge. (ekstern lenke)
• Karimi, Elham; Ramos, Miguel; Gonçalves, Jorge M.S. et al. (2017). Comparative metagenomics reveals the distinctive adaptive features of the Spongia officinalis endosymbiotic consortium. (ekstern lenke)
• Hestetun, Jon Thomassen; Rapp, Hans Tore; Xavier, Joana R. (2016). Carnivorous sponges (Porifera, Cladorhizidae) from the Southwest Indian Ocean Ridge seamounts. (ekstern lenke)
• Gaspar, Helena; Cutignano, Adele; Grauso, Laura et al. (2016). Erylusamides: Novel atypical glycolipids from Erylus cf. deficiens. (ekstern lenke)
• Graca, Ana Patrícia; Viana, Flávia; Bondoso, Joana et al. (2015). The antimicrobial activity of heterotrophic bacteria isolated from the marine sponge Erylus deficiens (Astrophorida, Geodiidae). (ekstern lenke)
• Xavier, Joana R.; Tojeira, Inês; Soest, Rob W.M. Van (2015). On a hexactinellid sponge aggregation at the Great Meteor seamount (North-east Atlantic). (ekstern lenke)
• Cristobo, Javier; Rios, Pilar; Pomponi, Shirley A. et al. (2015). A new carnivorous sponge, Chondrocladia robertballardi sp. nov. (Porifera: Cladorhizidae) from two Northeast Atlantic seamounts. (ekstern lenke)
• Syoc, Robert van; Soest, Rob W.M. Van; Xavier, Joana R. et al. (2015). A Phylogenetic Overview of Sponge-inhabiting Barnacles and Their Host Specificity (Crustacea, Cirripedia). (ekstern lenke)
• Xavier, Joana R.; Cárdenas, Paco A.; Cristobo, Javier et al. (2015). Systematics and biodiversity of deep-sea sponges of the Atlanto-Mediterranean region. (ekstern lenke)
• Carvalho, Francisca; Pomponi, Shirley A.; Xavier, Joana R. (2015). Lithistid sponges of the upper bathyal of Madeira, Selvagens and Canary Islands, with description of a new species of Isabella. (ekstern lenke)
• Taboada, Sergi; Riesgo, Ana; Blasco, Gema et al. (2015). Development of 10 microsatellite markers for the Atlanto-Mediterranean sponge Petrosia ficiformis. (ekstern lenke)
• Hardoim, CC; Cardinale, M; Cúcio, AC et al. (2014). Effects of sample handling and cultivation bias on the specificity of bacterial communities in keratose marine sponges. (ekstern lenke)
• Cristobo, Javier; Rios, Pilar; Pomponi, Shirley A. et al. (2014). A new carnivorous sponge, Chondrocladia robertballardi sp. nov. (Porifera: Cladorhizidae) from two north-east Atlantic seamounts. (ekstern lenke)

Leder

• Xavier, Joana R.; Pomponi, Shirley A.; Kenchington, Ellen L. (2023). Editorial: Deep-sea sponge ecosystems: Knowledge-based approach towards sustainable management and conservation. (ekstern lenke)

Se en full oversikt over publikasjoner i Cristin

Xavier JR, Rees DJ, Pereira R, Colaço A, Pham CK and Carvalho FC (2021) Diversity, Distribution and Phylogenetic Relationships of Deep-Sea Lithistids (Porifera, Heteroscleromorpha) of the Azores Archipelago. Front. Mar. Sci. 8:600087.

Dudik O, Amorim S, Xavier JR, Rapp HT, Silva TH, Pires RA and Reis RL (2021) Bioactivity of Biosilica Obtained From North Atlantic Deep-Sea Sponges. Front. Mar. Sci. 8:637810.

Figueiredo C, Caetano M, Mil-Homens M, Tojeira I, Xavier JR, Rosa R, Raimundo J (2021) Rare earth and trace elements in deep-sea sponges of the North Atlantic. Marine Pollution Bulletin 166: 112217. 

Martins E, Rapp HT, Xavier JR, Diogo GS, Reis RL, Silva TH (2021) Macro and Microstructural Characteristics of North Atlantic Deep-Sea Sponges as Bioinspired Models for Tissue Engineering Scaffolding. Frontiers in Marine Science 7:613647.

Howell KL, Hilário A, Allcock AL, …, Xavier JR (2020) A Decade to Study Deep-Sea Life. Nature Ecology and Evolution 5, 265-267.

Howell KL, Hilario A, Allcock AL, …, Xavier JR (2020) A blueprint for an inclusive, global deep-sea Ocean Decade field programme. Frontiers in Marine Science 7. 

Carvalho FC, Cárdenas P, Rios P, Cristobo J, Rapp HT, Xavier JR (2020) Rock sponges (lithistid Demospongiae) of the Northeast Atlantic seamounts, with the description of ten new species. PeerJ 8, e8703. 

Ríos P, Prado E, Carvalho FC, Sánchez F, Rodríguez-Basalo A, Xavier JR, Ibarrola TP, Cristobo J (2020) Community Composition and Habitat Characterization of a Rock Sponge Aggregation (Porifera, Corallistidae) in the Cantabrian Sea. Frontiers in Marine Science 7.

Rooks C, Fang JKH, Mørkved PT, Zhao R, Rapp HT, Xavier JR, Hoffmann F (2020) Deep-sea sponge grounds as nutrient sinks: High denitrification rates in boreo-arctic sponges. Biogeosciences, 17, 1231–1245. 

Xavier JR, Carreiro-Silva M, Colaço A, Le Bris N, Levin L (2019) Vulnerabilities: invertebrate taxa (VME indicators). In: Levin L, Baker M, Thompson T (Eds.) Deep-ocean climate change impacts on habitat, fish and fisheries. FAO Fisheries and Aquaculture Technical Paper No. 638. Rome, FAO. 186 pp.

Otero, MM, Serena F, Gerovasileiou V, Barone M, Bo M, Arcos M, Vulcano A, Xavier JR (2019) Identification guide of vulnerable species incidentally caught in Mediterranean fisheries. Malaga, Spain. International Union for Conservation of Nature (IUCN).

Hawkes N, Korabik M, Beazley L, Rapp HT, Xavier JR, Kenchington E (2019) Glass sponge grounds on the Scotian Shelf and their associated biodiversity. Marine Ecology Progress Series 614, 91-109. 

Howell KL, Davies JS, Allcock AL, Braga-Henriques A, Buhl-Mortensen P, Carreiro-Silva M, Dominguez-Carrió C, Durden JM, Foster NL, Game CA, Hitchin B, Horton T, Hosking B, Jones DOB, Mah C, Marchais CL, Menot L, Morato T, Pearman TRR, Piechaud N, Ross RE, Ruhl HA, Saeedi H, Stefanoudis PV, Taranto GH, Thompson MB, Taylor JR, Tyler P, Vad J, Victorero L, Vieira RP, Woodall LC, Xavier JR, Wagner D (2019) A framework for the development of a global standardised marine taxon reference image database (SMarTaR-ID) to support imagebased analyses. PLoS ONE 14.

Ramiro-Sánchez B González-Irusta JM, Henry L-A, Cleland J, Yeo I, Xavier JR, Carreiro-Silva M et al (2019) Characterization and Mapping of a Deep-Sea Sponge Ground on the TropicSeamount (Northeast Tropical Atlantic): Implications for Spatial Management in the High Seas. Frontiers in Marine Science 6

Riesgo A, Taboada S, Pérez-Portela R, Melis P, Xavier JR, Blasco G, López-Legentil S (2019) Genetic diversity, connectivity and gene flow along the distribution of the emblematic Atlanto-Mediterranean sponge Petrosia ficiformis (Haplosclerida, Demospongiae). BMC Evolutionary Biology 19: 24.

Alvizu A, Xavier JR, Rapp HT (2019) Description of new chiactine-bearing sponges provides insights into the higher classification of Calcaronea (Porifera: Calcarea). Zootaxa 4615, 201-251. 

Cassarino L, Coath CD, Xavier JR, Hendry KR (2018) Silicon isotopes of deep-sea sponges: new insights into biomineralisation and skeletal structure. Biogeosciences 15, 6959-6977. 

Beazley LI, Wang Z, Kenchington EL, Yashayaev Y, Rapp HT, Xavier JR, Murillo FJ, Fenton D, Fuller SD (2018) Predicted distribution of the glass sponge Vazella pourtalesi on the Scotian Shelf and persistence in the face of climatic variability. PLoS ONE 13(10): e0205505. 

Cárdenas P, Vacelet J, Chevaldonnée P, Pérez T, Xavier JR (2018) From marine caves to the deep sea, a new look at Caminella (Demospongiae, Geodiidae) in the Atlanto-Mediterranean region. Zootaxa 4466(1), 174-196.

Alvizu A, Eilertsen MH, Xavier JR, Rapp HT (2018) Increased taxon sampling provides new insights into the phylogeny and evolution of the subclass Calcaronea (Porifera, Calcarea). Organisms Diversity and Evolution 18(3), 279-290.

Dudik O, Leonor I, Xavier JR, Rapp HT, Pires RA, Silva TH, Reis RL (2018) Sponge-derived silica for tissue regeneration. Materials Today 21(5), 577-578.

Karimi E, Ramos M, Gonçalves JMS, Xavier JR, Reis MP and Costa R (2017) Comparative Metagenomics Reveals the Distinctive Adaptive Features of the Spongia officinalis Endosymbiotic Consortium. Frontiers in Microbiology 8, 2499. doi: 10.3389/fmicb.2017.02499 

Xavier JR, Bo M (2017) Deep-sea sponges of the Mediterranean Sea. http://www.fao.org/publications/card/en/c/df94258d-ed23-4a65-9fd9-d344f75f746e/

Hestetun JT, RappHT, Xavier JR (2017) Carnivorous sponges (Porifera, Cladorhizidae) from the Southwest Indian Ocean Ridge seamounts. Deep Sea Research II 137, 166-189.

Gaspar H, Cutignano A, Grauso L, Neng N, Cachatra V, Fontana A, Xavier JR, Cerejo M, Vieira, H, Santos S (2016) Erylusamides: Novel Atypical Glycolipids from Eryluscf. deficiens. Marine Drugs 14(10), 179.

Taboada S, Riesgo A, Blasco G, Solà J, Xavier JR, López-Legentil S (2015) Development of 10 microsatellite markers for the Atlanto-Mediterranean sponge Petrosia ficiformis. Conservation Genetics Resources 7(4), 895-897.

Xavier JR, Cárdenas P, Cristobo J, Van Soest RWM, Rapp HT (2015) Systematics and biodiversity of deep-sea sponges of the Atlanto-Mediterranean region (Foreword). JMBA of the UK 95(7), 1285-1286.

Xavier JR, Tojeira I, Van Soest RWM (2015) On a hexactinellid sponge aggregation at the Great Meteor seamount (North-east Atlantic). JMBA of the UK 95(7), 1389-1394.

Carvalho F, Pomponi SA, Xavier JR (2015) Lithistid sponges of the upper bathyal of Madeira, Selvagens and Canary Islands with description of a new species of Isabella. JMBA of the UK 95(7), 1287-1296.

Cristobo J, Pomponi SA, Rios P, Xavier JR (2015) A new carnivorous sponge, Chondrocladia robertballardi sp. nov. (Porifera: Cladorhizidae) from two Northeast Atlantic seamounts. JMBA of the UK 95(7), 1345-1352.

Van Syoc, Van Soest RWM, Xavier JR, Hooper JNA (2015) A Phylogenetic Overview of Sponge-inhabiting Barnacles and Their Host Specificity (Crustacea, Cirripedia). Proceedings of the California Academy of Sciences 62(11), 331-357.

Graça AP, Viana F, Bondoso J, Correia MI, Gomes L, Humanes M, Reis A, Xavier JR, Gaspar H, Lage OM (2015) The antimicrobial activity of heterotrophic bacteria isolated from the marine sponge Erylus deficiens (Astrophorida, Geodiidae). Front. Microbiol. 6, 389.

Hardoim, CCP, Cardinale M, Cúcio ACB, Esteves, AIS, Berg G, Xavier JR, Cox CJ, Costa R (2014) Effects of sample handling and cultivation bias on the specificity of bacterial communities in keratose marine sponges. Frontiers in Microbiology 5, 611.

Graça AP, Bondoso J, Gaspar H, Xavier JR, Monteiro MC, de la Cruz M, Oves-Costales D, Vicente F, Lage OM (2013) Antimicrobial activity of heterotrophic bacterial communities from the marine sponge Erylus discophorus(Astrophorida, Geodiidae). PLoS ONE 8(11): e78922.

Esteves AIS, Hardoim CCP, Xavier JR, Gonçalves MS, Costa R (2013) Molecular richness and biotechnological potential of bacteria cultured from Irciniidae sponges in the Northeast Atlantic. FEMS Microbiology Ecology, 85(3): 519-536.

Hardoim CCP, Esteves AIS, Pires FR, Gonçalves JMS, Cox CJ, Xavier JR, Costa R (2012) Phylogenetically and spatially close marine sponges harbour divergent bacterial communities. PLoS ONE 7(12), e53029.

Xavier JR, Van Soest RWM (2012) Diversity patterns and zoogeography of the Northeast Atlantic and Mediterranean shallow-water sponge fauna. Hydrobiologia 687(1), 107-125.

Araújo M, Xavier JR, Nunes CD, Vaz PD, Humanes M (2012) Marine sponge melanin: a new source of an old biopolymer. Structural Chemistry 23(1), 115-122.

Cárdenas P, Xavier JR, Reveillaud J, Schander C, Rapp HT (2011) Molecular phylogeny of the Astrophorida (Porifera, Demospongiae) reveals an unexpected high level of spicule homoplasy. PLoS ONE 6(4): e18318 

Xavier JR, Van Soest RWM, Breeuwer JAJ, Frias Martins AMF, Menken SBJ (2010b) Phylogeography, genetic diversity and structure of the poecilosclerid sponge Phorbas fictitius at oceanic islands. Contributions to Zoology 79, 119-129.

Xavier JR, Rachello-Dolmen PG, Parra-Velandia F, Schönberg CHL, Breeuwer JAJ, Van Soest RWM (2010a) Molecular evidence of cryptic speciation in the “cosmopolitan” excavating sponge Cliona celata (Porifera, Clionaidae). Molecular Phylogenetics and Evolution 56, 13-20.

Reveillaud J, Remerie T, Van Soest RWM, Erpenbeck D, Cárdenas P, Sofie Derycke S, Xavier JR, Rigaux A, Vanreusel A (2010) Species boundaries and phylogenetic relationships between Atlanto-Mediterranean shallow-water and deep-sea coral associated Hexadella species (Porifera, Ianthellidae). Molecular Phylogenetics and Evolution 56, 104-114.

Webster N, Xavier JR, Freckleton M, Motti C, Cobb R (2008) Shifts in microbial and chemical patterns within the marine sponge Aplysina aerophoba during a disease outbreak. Environmental Microbiology 10(12), 3366-3376. 

Marques D, Esteves A, Almeida M, Xavier JR, Humanes M (2008) Superoxide dismutase in the marine sponge Cliona celata. Marine Biology 153, 807-813.

Xavier JR, Van Soest RWM (2007) Demosponge fauna of Ormonde and Gettysburg Seamounts (Gorringe Bank, Northeast Atlantic): diversity and zoogeographical affinities. J. Mar. Biol. Ass. U. K. 87, 1643-1653.

Cárdenas P, Xavier JR, Tendal O, Schander C, Rapp HT (2007) Redescription and resurrection of Pachymatisma normani (Demospongiae: Geodiidae), with remarks on the genus Pachymatisma. J. Mar.Biol. Ass. U. K. 87, 1511-1525.