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Four strains of Hortaea werneckii were isolated from different substrates in Brazil (a salt marsh macrophyte, a bromeliad and a marine zoanthid) and had their identification confirmed by sequencing of the 26S rDNA D1/D2 domain or ITS region. Most of the strains were able to express amylase, lipase, esterase, pectinase and/or cellulase, enzymes that recognize components of plant cells as substrates, but did not express albuminase, keratinase, phospholipase and DNAse, whose substrates are animal-related. Urease production was positive for all isolates, while caseinase, gelatinase and laccase production were variable among the strains. All the strains grew in media containing up to 30% NaCl. We propose that the primary substrate associated with H. werneckii is plant-related, in special in saline environments, where the fungus may live as a saprophyte and decomposer. Infection of animal-associated substrates would be secondary, with the fungus acting as an opportunistic animal pathogen. All strains were resistant to fluconazole and presented high MIC for amphotericin B, while they were susceptible to all the other antifungal agents tested.

This report describes the occurrence of mycotic infection in a loggerhead turtle, Caretta caretta, found on Mostardas beach in the state of Rio Grande do Sul, Southern Brazil. The specimen was observed alive, emaciated, and died the following day. A necropsy was performed soon after death and tissue samples routinely processed for histopathological and molecular evaluation. Significant pathological alterations included multifocal to coalescing, 0.5-4 cm in diameter nodules were observed throughout the peritoneum and kidneys that revealed caseous, grayish content when sectioned; histopathological evaluation revealed severe peritonitis and nephritis associated with intralesional fungi. Fungal PCR that targeted the internal transcribed spacer region of fungi revealed three different species of fungi: Cladosporium cladosporioides and Alternata arborescens within the kidneys while Ampelomyces sp. was identified within peritoneal granulomas. C. cladosporioides and A. arborescens are melanized fungi that produce phaeohyphomycosis in a wide range of species. However, the importance of the identification of the mycoparasite Ampelomyces sp. DNA within the peritoneal granulomas remains unclear.

Chromoblastomycosis is a chronic cutaneous and subcutaneous mycosis. The management of this infection continues to be challenging because there is no consensus on the therapeutic regimen. We report here a case of a 69-year-old male patient with cauliflower-like lesions on his left leg and foot. He had already been treated with itraconazole at a dose of 200 mg/day for 5 months, with mycological cure for all the affected areas. However, the lesions relapsed at both sites, and treatment with itraconazole was resumed at the dose previously used. Initially, direct mycological examination, cultural, and microculture slide observation were performed. Afterward, sequencing of the ITS1-5.8S rDNA-ITS2 region of the fungal DNA and evaluation of its susceptibility to antifungal agents alone and in combination were performed. In direct mycological examination, the presence of sclerotic cells was verified, and the fungus was identified as Fonsecaea based on cultural and microscopic examinations. Identification as Fonsecaea monophora was confirmed after sequencing of the ITS region and phylogenetic analysis. The isolate was susceptible to itraconazole and terbinafine. The combinations of amphotericin B and terbinafine and terbinafine and voriconazole were synergistic. The use of drugs for which the causative agent is susceptible to singly or in combination may be an alternative for the treatment of mycosis. Furthermore, the identification of the agent by molecular techniques is important for epidemiological purposes. To the best of our knowledge, this is the first case of relapsed chromoblastomycosis caused by F. monophora in Brazil.

Knowledge of natural ecology is essential for a better understanding of pathogenicity and opportunism in black yeast-like fungi. Although etiological agents of diseases caused by these fungi are supposed to originate from the environment, their isolation from nature is difficult. This is probably due to their oligotrophic nature, low competitive ability, and, overall, insufficient data on their natural habitat. We obtained environmental samples from mangrove areas where mortalities by lethargic crab disease (LCD) are reported and areas without disease recorded. Isolation of chaetothyrialean black yeasts and relatives was performed using a highly selective protocol. Species-specific primers were used to determine if these isolates represented Exophiala cancerae or Fonsecaea brasiliensis, two proven agents of LCD, in order to test hypotheses about the origin of the disease. Isolates, identified by morphology as Fonsecaea- or Exophiala-like, were tested specific diagnostic markers for the fungi associated with LCD. Although several black fungi were isolated, the main causative agent of the LCD, E. cancerae, was not found. Molecular markers for F. brasiliensis revealed 10 positive bands for isolates from biofilms on mangrove leaves, branches, and aerial roots, of which four were confirmed by ITS sequencing. The absence of E. cancerae in environmental samples suggests that the species is dependent on the crab, as a genuine pathogen, different from F. brasiliensis, which is probably not dependent on the host species, U. cordatus. However, we did not attempt isolation from the marine water, which may represent the pathway of dispersion of the black yeast species between neighbor mangroves.

Cryptostegia madagascariensis is a plant native from Madagascar, belonging to the Apocynaceae that is invading the native vegetation in Northeast Brazil and threatening the unique riverine formations dominated by the carnauba palm. Individuals of C. madagascariensis cultivated in the campus of the Universidade Federal de Viçosa, state of Minas Gerais, Brazil, showing leaf spot symptoms of unknown etiology were observed. Two fungal species were found associated to such leaf spots: Colletotrichum gloeosporioides and a new species of Pseudocercospora. The latter was named Pseudocercospora cryptostegiae-madagascariensis and described herein. The discovery of those two fungal pathogens on C. madagascariensis coincide with the recognition that the weedy vine that is involved in the infestations in the Northeast of Brazil is not Cryptostegia grandiflora as formerly reported. These mycological findings are of greater importance now since C. madagascariensis is likely to become a target for biological control together with its former status in Brazil of an ornamental plant of limited relevance.