Botanica Marina 2017; 60(4): 361–362 Editorial Ka-Lai Pang and E. B. Gareth Jones Recent advances in marine mycology DOI 10.1515/bot-2017-0048 RNA-tag sequencing and fluorescent staining of samples, Richards et al. (2015) found low fungal abundance in The previous special issue of Botanica Marina on Marine upper seawater column samples. This is not surprising as Mycology was published in 2010 (Jones and Pang 2010), low organic matter in seawater does not support a stable when the number of known marine fungi was 530 species population of fungi; the exceptions are those that occur (Jones et al. 2009). Jones et al. (2015) updated this figure on phytoplankton. Also, recent molecular studies have to 1112 species (in 472 genera), which included newly repeatedly discovered the dominance of the Ascomycota described taxa, with the inclusion of the Chytridiomycota, and the Basidiomycota in seawater/sediments, without marine yeasts and a broader definition of what constitutes acknowledging the individual species, thus making com- a marine fungus (Pang et al. 2016). The documentation parisons between different studies difficult (Jones et al. of new marine fungi and new records brings the current 2015, Richards et al. 2015, Picard 2016, Hasset et al. 2017). total to 1206 (www.marinefungi.org, 2017). Jones (2011) There is therefore a gulf in appreciation about what is regarded these figures as an underestimate and suggested known about marine fungi using three approaches in their there may be as many as 10,000 marine fungi, indicat- documentation: (a) substrate based studies, (b) isolation ing where these missing fungi might be found. However, from seawater and (c) DNA sampling of water, sediments, controversy surrounds the diversity of marine fungi with often at great depths in the ocean. Although marine fungi Richards et al. (2012) concluding that fungi are low in are worldwide in their distribution, there are great differ- both diversity and abundance in marine environments. ences in their diversity in tropical, temperate and cold They questioned “Are we overlooking a large diversity of water habitats. Culture-independent studies have been fungi?” Furthermore, Tisthammer et al. (2016) stated that used only recently to study the diversity of marine fungi very little is known about the global distribution of marine and much greater sampling is required to obtain a full fungi and that marine fungi are understudied when com- picture of their occurrence and distribution. Another area pared to other microorganisms. that requires greater study is the much-neglected docu- Marine fungi are heterotrophic organisms, relying mentation of parasitic fungi and fungal-like organisms on degrading organic substrates for growth and reproduc- parasitizing plankton and marine invertebrates. This may tion, including plant-based substrata, macroalgae, animal be attributed to the lack of fresh material of epizootics and remains (Vrijmoed 2000). These substrates are abundant the techniques available for their study. This special issue in coastal environments and, therefore, research on has gathered up active marine mycologists to give updates marine fungi has been mainly focussed on fungi fruit- on marine mycology in the areas related to ecology, phy- ing on substrata in these environments, where they play logeny, pathology and applied aspects. They have also a significant role in nutrient cycling (Pang et al. 2016). highlighted the gaps of knowledge in marine mycology, Recent culture-independent analyses of fungal sequenc- suggesting further work in ecologically and industrially ing obtained from seawater and sediment samples have important but understudied groups of fungi. revealed a high abundance/richness of sequences related The recent research effort in Taiwan, the Middle East, to the Ascomycota and the Basidiomycota and possible Thailand and Arctic areas has increased our understand- new lineages of fungi early in the evolution of Fungi using ing of the diversity of marine fungi in these regions. In this different regions of the ribosomal RNA genes (Richards special issue, Suetrong et al. report the diversity of marine et al. 2015, Picard 2016, Hasset et al. 2017). Interpretation fungi in eastern and southern Thai mangroves, while of the results from molecular studies has to be cautious. Räma et al. have prepared a list of marine fungi in the Seawater is a dispersal medium, not a growth substrate, Arctic region. Supaphon et al. have investigated the phylo- while sediment represents a niche for accumulation of genetic diversity of fungi associated with a few seagrass fungal propagules. Fungi in these substrates may not species collected in Thailand. Exploration of wider geo- represent the active marine populations as many fungal graphical locations always results in new marine fungi. propagules may be of freshwater/terrestrial origin. Using Abdel-Wahab et al. report five new marine fungi collected 362 K.-L. Pang and E.B.G. Jones: Recent advances in marine mycology from various countries including Japan, Malaysia, Saudi Hassett, B.T., A.L.L. Ducluzeau, R.E. Collins and R. Gradinger. 2017. Arabia, Thailand and Turkey. Lulworthia grandispora is Spatial distribution of aquatic marine fungi across the western Arctic and sub-Arctic. Environ. Microbiol. 19: 475–484. transferred to a new genus Sammeyersia based on mor- Jones, E.B.G. 2011. Are there more marine fungi to be described? phology and sequence analysis in the same study. Jones Bot. Mar. 54: 343–354. et al. also make two new combinations: Aniptodera lig- Jones, E.B.G. and K.L. Pang. 2010. 11th International Marine and natilis to Aniptosporopsis gen. nov. and A. longispora to Freshwater Mycology Symposium, Taichung, Taiwan ROC, Paraaniptodera gen. nov.; a taxonomic review of the Halo- November 2009. Bot. Mar. 53: 475–478. sphaeriaceae is provided in the same paper. Jones, E.B.G., J. Sakayaroj, S. Suetrong, S. Somrithipol and K.L. Pang. 2009. Classification of marine Ascomycota, anamorphic Marine fungi are known to produce bioactive sec- taxa and Basidiomycota. Fungal Divers. 35: 1–187. ondary metabolites and fatty acids. Zhong et al. optimize Jones, E.B.G., S. Suetrong, J. Sakayaroj, A.H. Bahkali, M.A. fermentation conditions including nitrogen and carbon Abdel-Wahab, T. Boekhout, and K.L. Pang. 2015. Classification sources and fermentation temperature to investigate of marine Ascomycota, Basidiomycota, Blastocladiomycota and microbial oil production by a Fusarium sp. isolated from Chytridiomycota. Fungal Divers. 73: 1–72. Massana, R., A. Gobet, S. Audic, D. Bass, L. Bittner, C. Boutte, A. seawater. Unagul et al. evaluate the polyunsaturated fatty Chambouvet, R. Christen, J.M. Claverie, J. Decelle, et al. 2015. acid profile of thraustochytrids isolated from fallen man- Marine protist diversity in European coastal waters and sedi- grove leaves in Thailand. They have also tested several ments as revealed by high-throughput sequencing. Environ. methods for cryopreservation of the thraustochytrids. Microbiol. 17: 4035–4049. From an environmental point of view, marine fungi Pang, K.L., D.P. Overy, E.B.G. Jones, M.D.L. Calado, G. Burgaud, A.K. produce degradative enzymes to remove chemical pollut- Walker, J.A. Johnson, R.G. Kerr, H.J. Cha and G.F. Bills. 2016. ‘Marine fungi’ and ‘marine-derived fungi’ in natural product ants, and Velmurugan et al. have evaluated the ability of chemistry research: toward a new consensual definition. a Paecilomyces sp. to degrade several polycyclic aromatic Fungal Biol. Rev. 30: 163–175. hydrocarbons and their biochemical response using a pro- Picard, K.T. 2016. Coastal marine habitats harbor novel early- teomic approach. diverging fungal diversity. Fungal Ecol. 25: 1–13. Recent studies have suggested the prevalence of the Richards, T.A., M.D.M. Jones, G. Leonard and D. Bass. 2012. Marine fungi: their ecology and molecular diversity. Annu. Rev. Mar. Chytridiomycota in seawater; this group alone accounted Sci. 4: 495–522. for more than 60% of the rDNA sequences sampled in Richards, T.A., G. Leonard, F. Mahé, J. Del Campo, S. Romac, M.D. six near-shore sites around Europe (Massana et al. 2015, Jones, F. Maguire, M. Dunthorn, C. De Vargas, R. Massana et al. Richards et al. 2015) and, in Arctic and sub-Arctic coastal 2015. Molecular diversity and distribution of marine fungi habitats, they have been described as the most abun- across 130 European environmental samples. Proc. R. Soc. B dant fungal group (Hassett and Gradinger 2016, Hassett 282: 20152243. Tisthammer, K.H., G.M. Cobian and A.S. Amend. 2016. Global et al. 2017). Many of these species cause diseases of biogeography of marine fungi is shaped by the environment. marine organisms in natural environment and in mari- Fungal. Ecol. 19: 39–46. culture. Scholz et al. report on the effects of environmen- Vrijmoed, L.L.P. 2000. Isolation and culture of higher filamentous tal parameters on infection prevalence in diatoms while fungi. In: (K.D. Hyde, S.B. Pointing, eds) Marine mycology-A Gleason et al. and Collier et al. have provided reviews practical approach. Fungal Diversity Press, Hong Kong. pp. 1–20. of the diseases of molluscs caused by Perkinsozoa and Labyrinthulomycota. Corresponding author: Ka-Lai Pang, Institute of Marine Biology and Centre of Excellence for the Oceans, National Taiwan Ocean University, 2 Pei-Ning Road, Keelung 20224, Taiwan (R.O.C.), References e-mail: [email protected] E. B. Gareth Jones: Department of Entomology and Plant Pathology, Hassett, B.T. and R. Gradinger. 2016. Chytrids dominate arctic marine Faculty of Agriculture, Chiang Mai University, Huay Keaw Road, fungal communities. Environ. Microbiol. 18: 2001–2009. Suthep, Muang District, Chiang Mai Province, Thailand 50200.