Macroalgae of the genera Fucus, Ulva, and Enteromorpha are typically abundant in estuaries. Endophytic fungi may have beneficial effects on the hosts affecting their ability to cope with stress. They are also a source of biologically active compounds. However, little is known about the endophytic fungi that colonize these macroalgae. Endophytic isolates were obtained from macroalgae from various sites in the estuary Ria de Aveiro (Portugal), as well as from saline water and sponges. Six Acremonium-like species could not be affiliated to any known species. Phylogenetic analyses based on internal transcribed spacer (ITS) region of the ribosomal DNA and β-tubulin (tub2) and actin (act1) genes placed these species in the genera Emericellopsis and Parasarocladium, but distinct from all currently known species. Although sharing morphological characteristics with the most closely related species, these genera differ in micromorphological and molecular characters. Thus, three novel species of Emericellopsis (E. cladophorae, sp. nov., E. enteromorphae, sp. nov., and E. phycophila, sp. nov.) and three novel species of Parasarocladium (P. aestuarinum, sp. nov., P. alavariense, sp. nov., and P. fusiforme, sp. nov.) are proposed.
Keywords: 6 new taxa; Acremonium; endophyte; halotolerance; marine fungi; phylogeny; salt marsh.