NEWS - Researchers report a new species of deep-sea fungus, Oceanitis abyssalis, described based on SU rDNA sequence analysis and morphological characteristics. The specimen was found attached to a branch of Prunus sp. at a depth of 5707 meters on the abyssal plain in the Northwest Pacific Ocean, east of the Japanese Islands.
This discovery is the deepest recorded for a marine fungus. Previous research by an international team in the Ocean Species Discoveries project reported 11 new species of ocean animals at a depth of 7000 meters.
Oceanitis Kohlm (1977) grows on a variety of plant species in a variety of coastal to deep-sea environments. This genus is also widespread in geologically isolated deep-sea areas as one of the most successful fungal taxa in these environments. The thick peridium allows it to adapt to extreme deep-sea conditions.
The morphology of O. abyssalis is very similar to O. scuticella Kohlmeyer, but O. abyssalis having unicellular ascospores, smaller deciduous polar appendages and occasionally tree-like appendages, semi-persistent asci, smaller ascomata that are drop-shaped and cream-colored.
Yuriko Nagano from the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) in Yokosuka and Mohamed Abdel-wahab from Sohag University in Sohag and their team also reviewed the taxonomic status of O. scuticella in the original phylogenetic tree, which is still unclear due to the lack of genetic information and specimen access.
However, the molecular and morphological characteristics of specimens previously identified as O. scuticella likely include several undescribed cryptic species. In particular, the Kuril-Kamchatka Trench material (M0229768) previously identified as O. scuticella is thought to be a representative of O. abyssalis.
The team showed that several deep-sea fungal species are able to colonize wood with intact bark. O. abyssalis has an appendage structure that helps these fungi to settle on submerged wood. Previously, the presence of bark inhibits colonization of deep-sea fungi on wood.
Comparative genomic analysis can provide important insights into the adaptation, evolution and ecology of deep-sea fungi. This genus produces enzymes to degrade submerged wood in an environment that is completely different from the terrestrial environment.
Original research
Yuriko Nagano, Mohamed A. Abdel-wahab, Ryota Nakajima, Akinori Yabuki (2024). Oceanitis abyssalis sp. nov., a new deep-sea fungus from sunken wood collected at the depth of 5707 m in the Northwest Pacific Ocean. Phytotaxa 663 (4): 171-183 DOI:10.11646/phytotaxa.663.4.1
This discovery is the deepest recorded for a marine fungus. Previous research by an international team in the Ocean Species Discoveries project reported 11 new species of ocean animals at a depth of 7000 meters.
Oceanitis Kohlm (1977) grows on a variety of plant species in a variety of coastal to deep-sea environments. This genus is also widespread in geologically isolated deep-sea areas as one of the most successful fungal taxa in these environments. The thick peridium allows it to adapt to extreme deep-sea conditions.
The morphology of O. abyssalis is very similar to O. scuticella Kohlmeyer, but O. abyssalis having unicellular ascospores, smaller deciduous polar appendages and occasionally tree-like appendages, semi-persistent asci, smaller ascomata that are drop-shaped and cream-colored.
Yuriko Nagano from the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) in Yokosuka and Mohamed Abdel-wahab from Sohag University in Sohag and their team also reviewed the taxonomic status of O. scuticella in the original phylogenetic tree, which is still unclear due to the lack of genetic information and specimen access.
However, the molecular and morphological characteristics of specimens previously identified as O. scuticella likely include several undescribed cryptic species. In particular, the Kuril-Kamchatka Trench material (M0229768) previously identified as O. scuticella is thought to be a representative of O. abyssalis.
The team showed that several deep-sea fungal species are able to colonize wood with intact bark. O. abyssalis has an appendage structure that helps these fungi to settle on submerged wood. Previously, the presence of bark inhibits colonization of deep-sea fungi on wood.
Comparative genomic analysis can provide important insights into the adaptation, evolution and ecology of deep-sea fungi. This genus produces enzymes to degrade submerged wood in an environment that is completely different from the terrestrial environment.
Original research
Yuriko Nagano, Mohamed A. Abdel-wahab, Ryota Nakajima, Akinori Yabuki (2024). Oceanitis abyssalis sp. nov., a new deep-sea fungus from sunken wood collected at the depth of 5707 m in the Northwest Pacific Ocean. Phytotaxa 663 (4): 171-183 DOI:10.11646/phytotaxa.663.4.1