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Delimitation of species boundaries within the fungal genus Diaporthe has been challenging, but the analyses of combined multilocus DNA sequences has become an important tool to infer phylogenetic relationships and to circumscribe species. However, analyses of congruence between individual gene genealogies and the application of the genealogical concordance principle have been somehow overlooked. We noted that a group of species including D. amygdali, D. garethjonesii, D. sterilis, D. kadsurae, D. ternstroemia, D. ovoicicola, D. fusicola, D. chongqingensis and D. mediterranea, commonly known as D. amygdali complex, occupy a monophyletic clade in Diaporthe phylogenies but the limits of all species within the complex are not entirely clear. To assess the boundaries of species within this complex we employed the Genealogical Concordance Phylogenetic Species Recognition principle (GCPSR) and coalescence-based models: General Mixed Yule-Coalescent (GMYC) and Poisson Tree Processes (PTP). The incongruence detected between individual gene phylogenies, as well as the results of coalescent methods do not support the recognition of lineages within the complex as distinct species. Moreover, results support the absence of reproductive isolation and barriers to gene flow in this complex, thus providing further evidence that the D. amygdali species complex constitutes a single species. This study highlights the relevance of the application of the GCPSR principle, showing that concatenation analysis of multilocus DNA sequences, although being a powerful tool, might lead to an erroneous definition of species limits. Additionally, it further shows that coalescent methods are useful tools to assist in a more robust delimitation of species boundaries in the genus Diaporthe., (Copyright © 2021 British Mycological Society. Published by Elsevier Ltd. All rights reserved.)

Lignicolous marine fungi are a particular group of microorganisms that are typically found in mangroves, salt marshes, and estuaries, normally associated with driftwood or submerged wood. During investigations of lignicolous fungi occurring in the estuary Ria de Aveiro, Portugal, wood baits were submerged in a marina for 1 year. Seventeen distinct marine fungal species were identified, with the most abundant taxa belonging to the family Lulworthiaceae. Through single- and multilocus phylogenies based on sequences of the internal transcribed spacer (ITS) region and large subunit (28S) and small subunit (18S) of the ribosomal RNA gene cluster in combination with morphological and physiological data, we describe Remispora submersa , sp. nov., and Zalerion pseudomaritima , sp. nov., as novel species. Additionally, we propose that Papulaspora halima , a species whose taxonomic placement has been somehow confusing, be transferred to the genus Paralulworthia as Paralulworthia halima .

Blueberry, an increasingly cultivated fruit crop in Portugal, is known to be susceptible to twig blight and dieback caused by species of Diaporthe . The diversity of Diaporthe species associated with symptomatic and asymptomatic Vaccinium corymbosum plants in Portugal was assessed. A multilocus sequence analysis of the rDNA internal transcribed spacer (ITS) region and the translation elongation factor 1-alpha ( tef1-α ), β-tubulin ( tub2 ), calmodulin ( cal ), and histone 3 ( his3 ) genes revealed the presence of Diaporthe foeniculina, Diaporthe rudis , and four new species, which are described as Diaporthe crousii, Diaporthe phillipsii, Diaporthe rossmaniae , and Diaporthe vacuae . These new species were characterized in terms of their morphology, mating strategies, and temperature growth requirements. In artificial inoculation trials of V. corymbosum cv. Bluecrop plants, all Diaporthe species caused minor symptoms. Further, no differences in aggressiveness were apparent between species. This study provides the first survey of Diaporthe species associated with blueberry twig blight and dieback in Portugal. It disclosed the occurrence of a diverse assemblage of Diaporthe species, whose status and impact as pathogens of blueberry is not yet fully understood.