Brachycephalus (Anura: Brachycephalidae) is a remarkable genus of miniaturized frogs of the Brazilian Atlantic Rainforest. Many of its species are highly endemic to cloud forests, being found only on one or a few mountaintops. Such level of microendemism might be caused by their climatic tolerance to a narrow set of environmental conditions found only in montane regions. This restriction severely limits the chance of discovery of new species, given the difficulty of exploring these inaccessible habitats. Following extensive fieldwork in montane areas of the southern portion of the Atlantic Rainforest, in this study we describe seven new species of Brachycephalus from the states of Paraná and Santa Catarina, southern Brazil. These species can be distinguished from one another based on coloration and the level of rugosity of the skin in different parts of their body. These discoveries increase considerably the number of described species of Brachycephalus in southern Brazil.
1 September 2016 in Molecular Phylogenetics and Evolution
Background: The flea toad Brachycephalus sulfuratus was recently described from southeastern and southern Brazil. In its description, the authors overlooked previous records of flea toads that had been identified as “Brachycephalus sp. nov.” and B. hermogenesi occurring in the same regions, which could suggest the possibility of up to three flea toads coexisting in southern Brazil. In addition, B. sulfuratus is characterized by substantial phenotypic variability, to an extent that compromises its current diagnosis with respect to its congener B. hermogenesi. Therefore, the current state-of-affairs regarding the geographical distribution of these two species and the identification of previously known populations is hitherto uncertain. Our goals are to reassess previous records of flea toads attributable to B. hermogenesi, B. sulfuratus and “Brachycephalus sp. nov.”, considering the description of B. sulfuratus, and to review the diagnosis of B. sulfuratus. Methods: A critical analysis of the species identity of flea toad specimens attributable to B. hermogenesi, B. sulfuratus, or to a potentially undescribed species from southeastern and southern Brazil was based either on the analysis of morphology or on their advertisement calls. These analyses include our independent examinations of specimens and, when not possible, examinations of published descriptions. To allow for a consistent comparison of advertisement calls between B. hermogenesi and B. sulfuratus, we made recordings of both species, including in the type locality of the former. Results: We found that morphological and call characters originally proposed as diagnostic for B. sulfuratus in relation to B. hermogenesi vary intraspecifically. Live individuals with ventral yellow spots correspond to B. sulfuratus; individuals without yellow spots can be either B. sulfuratus or B. hermogenesi. In preservative, they are indistinguishable. Previous records of Brachycephalus sp. nov. correspond to B. sulfuratus. We propose that the reduced number of notes per call and the presence of only isolated notes in the call of B. sulfuratus, as opposed to a high number of notes per call with isolated notes and note groups in the call of B. hermogenesi, as the only diagnostic characters between them. Regarding their distributions and based in our assessment, only B. sulfuratus occurs in southern Brazil, without any overlap with B. hermogenesi. There is a narrow gap between the distributions of these species around the southeast of the city of São Paulo. Our revision also revealed that some records previously attributed to B. hermogenesi in Rio de Janeiro and north São Paulo represent a distinct, unidentified flea toad that is not B. sulfuratus. Both species occur side by side in Corcovado, São Paulo, a locality from where five paratypes of B. hermogenesi were obtained. Biogeographic events that might have led to vicariance between B. hermogenesi and B. sulfuratus are discussed.
The phylogeny of the vertebrate pathogen Histoplasma capsulatum and its varieties was analyzed on the basis of GenBank data, comparing preceding papers that distinguished lineages on the basis of a much smaller dataset, partly dating back two decades. The aim was to establish the predictive value of individual research papers on biodiversity, which eventually may lead to altered nomenclature with large clinical consequences. A total of 1985 sequences of ITS, ARF, OLE and H-anti were downloaded. ITS showed insufficient resolution, and the sequences of the H-anti gene were too short to provide reliable conclusions. Ten major lineages from the seven reports were selected for comparison. Compared to the currently available global data, several earlier studies applied somewhat skewed datasets, biased towards the Americas. Possible separation of Indian and Indonesian lineages were consequently overlooked. Previously distinguished lineages were again recognized, but because of low bootstrap values and extensive genetic exchange, several of these do not deserve species status. No recombination was observed with North American H. mississippiense and H. ohiense. An African clade (var. duboisii) was individualized. Despite its position in close association with South American clades, histopathology and clinical course of this entity underlines that it has other evolutionary drivers. This might also hold true for the North African donkey disease caused by var. farciminosum, although strains analyzed thus far are indistinguishable from South American strains. On the basis of phylogenetic data, Indian and Indonesian clades are separate, but more clinical data are needed to establish their value as individual species.