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This study presents morphological and molecular evidence for the establishment of a new species of Lulworthia based on the evaluation of 11 isolates of Lulworthiales collected in two marinas on the west coast of Portugal initially classified as Lulworthia sp. Maximum likelihood and Bayesian methods were applied to obtain phylogenetic trees for 18S-28S and internal transcribed spacer (ITS1-5.8S-ITS2 = internal transcribed spacer [ITS]) nuc rDNA. The isolates consistently grouped together in a distinct and highly supported clade; all other Lulworthiales analyzed, including the available sequences of Lulworthia spp., segregated separately. These results were supported by common and distinctive morphological characters and enabled recognition and description of the new species Lulworthia atlantica. Two Portuguese isolates were confirmed as Lulworthia cf. purpurea, and two were confirmed as asexual morphs of Zalerion maritima.

The occurrence, diversity and similarity of marine fungi detected by the sum of direct and indirect observations in Fagus sylvatica and Pinus pinaster baits submerged at two Portuguese marinas are analyzed and discussed. In comparison with the data already published in 2010, the higher number of specimens considered in this study led to the higher number of very frequent taxa for these environments and substrata; the significant difference in substrata and also in fungal diversity detected at the two environments is also highlighted, in addition to the decrease in fungal similarity. Because the identification of Lulworthia spp., Fusarium sp., Graphium sp., Phoma sp. and Stachybotrys sp. down to species level was not possible, based only on the morphological characterization, a molecular approach based on the amplification of the LSU rDNA region was performed with isolates of these fungi. This was achieved for three isolates, identified as Fusarium solani, Graphium eumorphum and Stachybotrys chartarum. To achieve this with the other isolates which are more complex taxa, the sequencing of more regions will be considered.

This survey reports the occurrence, diversity and similarity of marine fungi associated with five categories of drift substrates (Arundo donax, Phragmites australis, Spartina maritima, "other stems" and driftwood) collected on four sandy beaches of the western coast of Portugal. "Other stems" and driftwood are composite samples with a variety of identified and unidentified pieces of non-woody and woody substrates respectively. Fifty-six taxa were identified, including 38 Ascomycota and 18 anamorphic fungi. Twenty-six taxa were generalists; however several cases of "substrate recurrence" were identified. The very frequent fungi differed among the categories of studied substrates, with the exception of Corollospora maritima, very frequent on four categories. Except for S. maritima, P. australis and driftwood, cases of multiple fungal colonization were rare. S. maritima was the single substrate with five different marine fungi on one sample, as well as with the highest number of very frequent fungi, highest percentage of colonization and average number of fungi per sample. Driftwood presented the highest value of fungal richness (37 taxa) and A. donax the lowest (22 taxa). ANOSIM analysis of similarity showed that all substrates supported different fungal communities with the exception of the pair P. australis/"other stems". The effect of sample size on estimated fungal richness was tested, and the results let us conclude that, although most of the sporadic fungi (<1% occurrence) will be detected only in a very large number of samples, 60 samples of A. donax and "other stems" and 70 samples of all the other substrates may suffice to assess their respective representative marine mycota.