Marine fungi

Marine fungi are <a href="/facts/Species/oDg6b96r">species</a> of <a href="/facts/Fungus/BHo5DP59">fungi</a> that live in <a href="/facts/Marine_(ocean)/8W8lYgjD">marine</a> or <a href="/facts/Estuary/WmkSInmK">estuarine</a> environments. They are not a <a href="/facts/Taxonomy_(biology)/Qkg8wuyw">taxonomic</a> group, but share a common habitat. Obligate marine fungi grow exclusively in the <a href="/facts/Marine_habitat/FQdopCYb">marine habitat</a> while wholly or sporadically submerged in sea water. Facultative marine fungi normally occupy terrestrial or freshwater habitats, but are capable of living or even <a href="/facts/Spore/6qDRdcrs">sporulating</a> in a marine habitat. About 2,149 species of marine fungi have been described, within eleven phyla and 856 genera, although only about 64 species have been fully genetically sequenced. Many species of marine fungi are known only from <a href="/facts/Spore/6qDRdcrs">spores</a> and it is likely a large number of species have yet to be discovered. In fact, it is thought that less than 1% of all marine fungal species have been described, due to difficulty in targeting marine fungal DNA and difficulties that arise in attempting to grow cultures of marine fungi. It is impracticable to culture many of these fungi, but their nature can be investigated by examining seawater samples and undertaking <a href="/facts/Ribosomal_DNA/r0Ah7R7L">rDNA</a> analysis of the fungal material found.
Different marine habitats support very different fungal communities. Fungi can be found in niches ranging from ocean depths and coastal waters to <a href="/facts/Mangrove_swamp/JreUUsuG">mangrove swamps</a> and estuaries with low salinity levels. Marine fungi can be <a href="/facts/Saprotrophic_nutrition/sJkDfrJW">saprobic</a> or <a href="/facts/Parasitism/HWPcgky7">parasitic</a> on animals, saprobic or parasitic on <a href="/facts/Algae/U1ftVKU3">algae</a>, saprobic on plants, or saprobic on dead wood.
There has been some debate as to what exactly a marine fungus should be defined as. A definition used previously was "individuals with a long-term presence and metabolic activities in a marine habitat." A more commonly used definition now is from Ka-Lai et al. 2016: "any fungus that is recovered repeatedly from marine habitats because: 1) it is able to grow and/or sporulate (on substrata) in marine environments; 2) it forms symbiotic relationships with other marine organisms; or 3) it is shown to adapt and evolve at the genetic level or be metabolically active in marine environments."

Marine fungi open-in-new

Marine fungi