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Salinity and temperature are two of the key environmental variables influencing the distribution of fungi. Results from the limited research available on the effects of salinity and temperature on growth and reproduction of chytrids were inconclusive. This study investigated the combined effects of salinity (0, 1, 2, 4, 8, 16, 32) and temperature (17, 24, 30 °C) on the growth rate of Alphamyces chaetifer (isolates IMB230, IMB231, IMB232) and Gorgonomyces haynaldii (IMB233, IMB237, IMB239) cultured from low-salinity water samples collected from coastal wetlands/ponds of eastern Taiwan. All isolates grew well at salinity 4 or below, irrespective of the incubation temperatures, although some grew significantly faster at 30 °C. No growth was observed at salinity 16 or 32. At or below 4, A. chaetifer IMB230 and IMB231, isolated from the same collection site where salinity was 2, produced the fastest growth rate at these salinities while G. haynaldii IMB237 and IMB239, isolated from water samples of zero salinity, had the slowest growth rate. These results agree with previous research that chytrids are sensitive to salinity, and may explain why only 27 culturable Chytridiomycota species and allied taxa have been documented from the marine environment. [ABSTRACT FROM AUTHOR]

The fungal community associated with marine crabs is poorly known, except for the fungi causing diseases of marine animals of economic value. In this study we examined the diversity of fungi cultured from carapace and gut of the marine crab Portunus sanguinolentus, and the identification was based on nucleotide BLAST search results of the internal transcribed spacers of rDNA (ITS). A total of 256 fungal isolates representing 23 species were cultured from seven individuals of P. sanguinolentus including two unidentified species. The majority of the species belong to the Ascomycota, while three species of the Basidiomycota were isolated from the gut. Overall, Candida tropicalis (45.70 %, percentage occurrence), Apiotrichum lignicola (8.98 %) and Rhodotorula sp. (8.20 %) were the dominant fungi on the crab. The most dominant fungi on the carapace were C. tropicalis (66.95 %), Emericellopsis maritima (8.47 %), A. lignicola and Purpureocillium lilacinum (both 4.24 %). In the gut, C. tropicalis (27.54 %), A. lignicola (16.67 %), Rhodotorula sp. (15.22 %) and Fusarium solani (14.49 %) were dominant. The fungal diversity in the gut of P. sanguinolentus was higher than on the carapace according to the diversity indices. Although some of the isolated fungi were reported to be pathogenic, none were reported as pathogens of crabs, and no disease symptoms were noticed from the crab samples. [ABSTRACT FROM AUTHOR]

An apparently undescribed lignicolous Dactylospora species was collected on a rocky shore in northern Taiwan. The ascomatal morphology of this fungus is similar to other marine Dactylospora species, whereas the unique feature of the new fungus is a distinct perispore forming an ascospore appendage, which comprises a thick and hyaline sheath connected at the septum that opens at both ends. Dactylospora vrijmoediae is described and illustrated as new to science. On the basis of a phylogenetic analysis of the partial 18S and 28S rRNA and RPB2 genes, D. vrijmoediae occurs with other marine species, D. haliotrepha, D. mangrovei, and the terrestrial Sclerococcum sphaerale in an unnamed clade within the Eurotiomycetes, Ascomycota. The marine Dactylospora species are distantly placed and are separated from the terrestrial Dactylospora species included in the analysis ( D. lobariella, D. imperfecta). [ABSTRACT FROM AUTHOR]

This paper reports the diversity of fungi associated with substrates collected at a shallow hydrothermal vent field at Kueishan Island, Taiwan, using both culture-based and metabarcoding methods. Culture of fungi from yellow sediment (with visible sulfur granules), black sediment (no visible sulfur granules), the vent crab Xenograpsus testudinatus, seawater and, animal egg samples resulted in a total of 94 isolates. Species identification based on the internal transcribed spacer regions of the rDNA revealed that the yellow sediment samples had the highest species richness with 25 species, followed by the black sediment (23) and the crab (13). The Ascomycota was dominant over the Basidiomycota; the dominant orders were Agaricales, Capnodiales, Eurotiales, Hypocreales, Pleosporales, Polyporales and Xylariales. Hortaea werneckii was the only common fungus isolated from the crab, seawater, yellow and black sediment samples. The metabarcoding analysis amplifying a small fragment of the rDNA (from 18S to 5.8S) recovered 7–27 species from the black sediment and 12–27 species from the yellow sediment samples and all species belonged to the Ascomycota and the Basidiomycota. In the yellow sediments, the dominant order was Pleosporales and this order was also dominant in the black sediment together with Sporidiobolales. Based on the results from both methods, 54 and 49 species were found in the black and yellow sediments, respectively. Overall, a higher proportion of Ascomycota (~70%) over Basidiomycota was recovered in the yellow sediment and the two phyla were equally abundant in the black sediment. The top five dominant fungal orders in descending order based on species richness were Pleosporales>Eurotiales>Polyporales>Hypocreales>Capnodiales in the black sediment samples, and Polyporales>Pleosporales>Eurotiales>Capnodiales>Hypocreales in the yellow sediment samples. This study is the first to observe a high diversity of fungi associated with various substrates at a marine shallow water hydrothermal vent ecosystem. While some fungi found in this study were terrestrial species and their airborne spores might have been deposited into the marine sediment, several pathogenic fungi of animals, including Acremonium spp., Aspergillus spp., Fusarium spp., Malassezia spp., Hortaea werneckii, Parengyodontium album, and Westerdykella dispersa, were recovered suggesting that these fungi may be able to cause diseases of marine animals. [ABSTRACT FROM AUTHOR]

A high diversity of fungi was discovered on various substrates collected at the marine shallow-water Kueishan Island Hydrothermal Vent Field, Taiwan, using culture and metabarcoding methods but whether these fungi can grow and play an active role in such an extreme environment is unknown. We investigated the combined effects of different salinity, temperature and pH on growth of ten fungi (in the genera Aspergillus, Penicillium, Fodinomyces, Microascus, Trichoderma, Verticillium) isolated from the sediment and the vent crab Xenograpsus testudinatus. The growth responses of the tested fungi could be referred to three groups: (1) wide pH, salinity and temperature ranges, (2) salinity-dependent and temperature-sensitive, and (3) temperature-tolerant. Aspergillus terreus NTOU4989 was the only fungus which showed growth at 45 °C, pH 3 and 30 ‰ salinity, and might be active near the vents. We also carried out a transcriptome analysis to understand the molecular adaptations of A. terreus NTOU4989 under these extreme conditions. Data revealed that stress-related genes were differentially expressed at high temperature (45 °C); for instance, mannitol biosynthetic genes were up-regulated while glutathione S-transferase and amino acid oxidase genes down-regulated in response to high temperature. On the other hand, hydrogen ion transmembrane transport genes and phenylalanine ammonia lyase were up-regulated while pH-response transcription factor was down-regulated at pH 3, a relative acidic environment. However, genes related to salt tolerance, such as glycerol lipid metabolism and mitogen-activated protein kinase, were up-regulated in both conditions, possibly related to maintaining water homeostasis. The results of this study revealed the genetic evidence of adaptation in A. terreus NTOU4989 to changes of environmental conditions. [ABSTRACT FROM AUTHOR]

This study investigated the morphological diversity of arenicolous marine fungi (only those forming fruiting bodies on sand grains) at 11 sandy beaches in Taiwan. The species of Corollospora were identified by ascospore morphology and confirmed through a phylogenetic analysis of the 28S rDNA with other published sequences. The phylogenetic analysis revealed four previously unknown clades of Corollospora spp. related to C. portsaidica, while differences in ascospore morphology of the isolates in these four clades were observed. A total of 13 species of arenicolous marine fungi was identified from the 11 sandy beaches, including two Arenariomyces spp., nine Corollospora spp. (including four unknown Corollospora clades), Kohlmeyeriella crassa and Carbosphaerella cf sp. Taan Beach had the highest species richness (eight species), followed by Yongzhen Sea Park and Pisirian (five species each). The Shannon's diversity index revealed the highest diversity at Taan Beach (1.51) over Pisirian (1.44), but the diversity was more even at the latter site (Pielou's evenness index = 0.9) compared with the former (0.73). Non-metric multidimensional scaling suggests that there was generally a divide in the fungal community composition between the east and the west coasts of Taiwan. [ABSTRACT FROM AUTHOR]

Reports on fungi occurring on marine crabs have been mostly related to those causing infections/diseases. To better understand the potential role(s) of fungi associated with marine crabs, this study investigated the culturable diversity of fungi on carapace of the marine shallow-water hydrothermal vent crab Xenograpsus testudinatus collected at Kueishan Island, Taiwan. By sequencing the internal transcribed spacer regions (ITS), 18S and 28S of the rDNA for identification, 12 species of fungi were isolated from 46 individuals of X. testudinatus: Aspergillus penicillioides, Aspergillus versicolor, Candida parapsilosis, Cladosporium cladosporioides, Mycosphaerella sp., Parengyodontium album, Penicillium citrinum, Penicillium paxili, Stachylidium bicolor, Zasmidium sp. (Ascomycota), Cystobasidium calyptogenae and Earliella scabrosa (Basidiomycota). With additional data from other published reports, a total of 26 species of fungi (23 Ascomycota, three Basidiomycota) have been recorded from X. testudinatus. Aspergillus is the most speciose genus on the crab, followed by Penicillium and Candida. All but one species (Xylaria arbuscula) had been previously isolated from substrates in the marine environment, although many are typical terrestrial taxa. None of the recorded fungi on X. testudinatus are reported pathogens of crabs, but some have caused diseases of other marine animals. Whether the crab X. testudinatus is a vehicle of marine fungal diseases requires further study. [ABSTRACT FROM AUTHOR]