Phylogenomic species delimitation in microendemic frogs of the Brazilian Atlantic Forest

The advent of next-generation sequencing allows researchers to use large-scale datasets for species delimitation analyses, yet one can envision an inflection point where the added accuracy of including more loci does not offset the increased computational burden. One alternative to including all loci could be to prioritize the analysis of loci for which there is an expectation of high informativeness. Here, we explore the issue of species delimitation and locus selection with montane species from two anuran genera that have been isolated in sky islands across the southern Brazilian Atlantic Forest: Melanophryniscus (Bufonidae) and Brachycephalus (Brachycephalidae). To delimit species, we obtained genetic data using target enrichment of ultraconserved elements from 32 populations (13 for Melanophryniscus and 19 for Brachycephalus), and we were able to create datasets that included over 800 loci with no missing data. We ranked loci according to their number of parsimony-informative sites, and we performed species delimitation analyses using BPP with the most informative 10, 20, 40, 80, 160, 320, and 640 loci. We identified three types of phylogenetic node: nodes with either consistently high or low support regardless of the number of loci or their informativeness and nodes that were initially poorly supported where support became stronger as we included more data. When viewed across all sensitivity analyses, our results suggest that the current species richness in both genera is likely underestimated. In addition, our results show the effects of different sampling strategies on species delimitation using phylogenomic datasets.

Redescription of the advertisement call of Brachycephalus tridactylus (Anura: Brachycephalidae)

Redescription of the advertisement call of Brachycephalus tridactylus (Anura: Brachycephalidae). Miniaturized frogs of the genus Brachycephalus have restricted geographical distributions throughout the Atlantic Forest. Ecological data for most species are scarce and advertisement calls have been described for only 12 of the 36 known species, including B. tridactylus. The considerable duration of note length of the advertisement call of B. tridactylus has been mentioned in comparative studies of vocalizations in Brachycephalus. The single original recording of B. tridactylus, together with recordings made in March 2016 at the type locality, were analyzed to document any variation and redescribe the advertisement call of the species. In the recent recordings of B. tridactylus, the average length of the call is 50.8 s and the call is composed of 10–13 notes emitted at a note rate of 3.7–8.3 notes per min. The notes are isolated and composed of 1–3 pulses, with the note duration varying from 0.002–0.021 s. These values are not consistent with the original description of the call of B. tridactylus. The note duration is 89% shorter and the original description does not include notes with 1–3 pulses. The notes of B. tridactylus have few pulses, whereas those of B. ephippium have several. The advertisement call of B. tridactylus differs from that of B. albolineatus and B. mirissimus by having only isolated notes.

A second record of the recently described Brachycephalus albolineatus Bornschein, Ribeiro, Blackburn, Stanley & Pie, 2016 (Anura, Brachycephalidae)

When Brachycephalus albolineatus was described, it was known only from its type locality in the state of Santa Catarina, Brazil. Here we provide a new record for the species. Collected specimens were identified in comparison with the type series. We collected 7 specimens in Morro do Garrafão, municipality of Corupá, state of Santa Catarina, at 500–530 m above sea level, in December 2016. The new record is 22 km away from the type locality and also extends the altitudinal distribution of the species, which was previously between 790–835 m above sea level.

A new species of Brachycephalus (Anura: Brachycephalidae) from southern Brazil

A new miniaturized frog of the genus Brachycephalus (Anura: Brachycephalidae) is described from Morro Santo Anjo in the municipality of Massaranduba, Santa Catarina, southern Brazil. Specimens were collected from the leaf litter between 470 and 540 above sea level. The new species is distinguished from all its congeners by the combination of the following characters: (1) body robust and bufoniform; (2) size snout-vent length 9.9–11.7 mm for males and 10.0–12.9 mm for females; (3) smooth dorsum; (4) general color (in life) orange with white dots and stripe in the middle of the head and along its vertebral column; (5) iris completely black; (6) advertisement call composed of note groups; (7) isolated notes with 1–3 pulses; and (8) short isolated notes (0.002–0.027 s). An estimate of the male density of the new species is also presented. Phylogenetic information indicates that the new species is part of the southernmost clade of Brachycephalus, which includes Brachycephalus fuscolineatus, B. albolineatus, and B. boticario. The severe anthropogenic impacts in and around the type locality indicate that immediate actions should be taken to ensure the long-term preservation of the new species.

GH11 xylanase from Aspergillus tamarii Kita: Purification by one-step chromatography and xylooligosaccharides hydrolysis monitored in real-time by mass spectrometry

The present study describes the one-step purification and biochemical characterization of an endo-1,4-β-xylanase from Aspergillus tamarii Kita. Extracellular xylanase was purified to homogeneity 7.43-fold through CM-cellulose. Enzyme molecular weight and pI were estimated to be 19.5kDa and 8.5, respectively. The highest activity of the xylanase was obtained at 60°C and it was active over a broad pH range (4.0-9.0), with maximal activity at pH 5.5. The enzyme was thermostable at 50°C, retaining more than 70% of its initial activity for 480min. The K_0.5 and V_max values on beechwood xylan were 8.13mg/mL and 1,330.20μmol/min/mg of protein, respectively. The ions Ba²⁺ and Ni²⁺, and the compounds β-mercaptoethanol and DTT enhanced xylanase activity, while the heavy metals (Co²⁺, Cu²⁺, Hg⁺, Pb²⁺ and Zn²⁺) strongly inhibited the enzyme, at 5mM. Enzymatic hydrolysis of xylooligosaccharides monitored in real-time by mass spectrometer showed that the shortest xylooligosaccharide more efficiently hydrolyzed by A. tamarii Kita xylanase corresponded to xylopentaose. In agreement, HPLC analyzes did not detect xylopentaose among the hydrolysis products of xylan. Therefore, this novel GH11 endo-xylanase displays a series of physicochemical properties favorable to its application in the food, feed, pharmaceutical and paper industries.

Is the taxonomy of <i>Brachycephalus</i> (Anura: Brachycephalidae) in need of rescue? A reply to Condez <i>et al.</i> (2017)

Brachycephalus is a fascinating genus of miniaturized frogs endemic to the Brazilian Atlantic Forest (Bornschein et al. 2016a). Given the many new species that have been recently discovered (20 species over the past 10 years [Frost 2017]) and their often microendemic distribution (see Bornschein et al. 2016a), there has been an increasing awareness about the need for more extensive field work to locate additional new species, to describe their geographical distributions, and to devise comprehensive efforts to ensure their conservation. In a recent correspondence in Zootaxa, Condez et al. (2017) singled out nine of those new species that have been described by our research group (Ribeiro et al. 2015; Pie & Ribeiro 2015; Bornschein et al. 2016b); two additional species (Ribeiro et al. 2017) were described after their paper was published. According to Condez et al. (2017), our species descriptions included "inadequate diagnoses, which lacked indispensable information for any further comparisons among species" (p. 395). Herein, we explore the extent to which their arguments would undermine the validity of those species.

Two new species of the Brachycephalus pernix group (Anura: Brachycephalidae) from the state of Paraná, southern Brazil

We describe two new species of miniaturized toadlet in the B. pernix group of Brachycephalus (Anura: Brachycephalidae) from the Atlantic Forest of the state of Paraná, southern Brazil. The first new species is distinguished from all congeners by the pale red coloration from the head to the pelvic region, with sides of the body and thighs dorsally yellowish green. It is known only from the type locality in a cloud forest at altitudes ranging between 1,144–1,228 m a.s.l. The second species, although more closely related to B. izecksohni, is morphologically similar to B. brunneus in its overall brown coloration, but distinct from that species in the color of the iris (black with conspicuous golden spots, instead of entirely black). It was found on three mountains, at altitudes between 1,095–1,320 m a.s.l., and in vegetation types including cloud forest, montane forest, and secondary forest. The two new species exhibit neither vertebral fusions nor osteoderms, but one has both a distinct neopalatine and well-developed odontoids on the maxillae. We discuss the conservation status of both species.

Phylogenetic relationships of diurnal, phytotelm-breeding Melanophryniscus (Anura: Bufonidae) based on mitogenomic data

Melanophryniscus is a bufonid frog genus with a broad geographic distribution over southeastern South America. In recent years, several new species of Melanophryniscus have been discovered in southern Brazil showing a distinctive life-history strategy for the genus - breeding in phytotelmata - as well as a strong association with high-altitude regions. In this study, we use mitogenomic data to infer the phylogenetic relationships among diurnal, phytotelm-breeding Melanophryniscus and to determine the timing of their divergence. We obtained the mitochondrial genomes (not including the control region) for eight individuals of Melanophryniscus representing all three described species (M. alipioi, M. milanoi, and M. xanthostomus), as well as some recently-discovered and potentially new species. Gene order was conserved in all species and corresponded to the general order found in bufonids. Although the phylogenetic relationships among the studied species was poorly supported, dating confirmed that they diverged during the Pleistocene, suggesting that phytotelm breeding could have arisen during drier periods in the glacial/interglacial cycles due to a decrease in the availability of permanent streams or ephemeral/temporary streams or ponds in which Melanophryniscus species commonly breed.

A new species of Brachycephalus (Anura: Brachycephalidae) from Santa Catarina, southern Brazil

A new species of Brachycephalus (Anura: Brachycephalidae) is described from the Atlantic Forest of northeastern state of Santa Catarina, southern Brazil. Nine specimens (eight adults and a juvenile) were collected from the leaf litter of montane forests 790-835 m above sea level (a.s.l.). The new species is a member of the pernix group by its bufoniform shape and the absence of dermal co-ossification and is distinguished from all its congeners by a combination of its general coloration (dorsal region of head, dorsum, legs, arms, and flanks light, brownish green to dark, olive green, with darker region in the middle of the dorsum and a white line along the vertebral column in most specimens) and by its smooth dorsum. The geographical distribution of the new species is highly reduced (extent of occurrence estimated as 25.04 ha, or possibly 34.37 ha). In addition, its habitat has experienced some level of degradation, raising concerns about the future conservation of the species. Preliminary density estimates suggest one calling individual every 3-4 m² at 815-835 m a.s.l. and every 100 m² at 790 m a.s.l. Together with the recently described B. boticario and B. fuscolineatus, the new species is among the southernmost species of Brachycephalus known to date.

Geographical and altitudinal distribution of Brachycephalus (Anura: Brachycephalidae) endemic to the Brazilian Atlantic Rainforest

Mountains of the Brazilian Atlantic Forest can act as islands of cold and wet climate, leading to the isolation and speciation of species with low dispersal capacity, such as the toadlet species of the genus Brachycephalus. This genus is composed primarily by diurnal species, with miniaturized body sizes (<2.5 cm), inhabiting microhabitats in the leaf litter of montane forests. Still, little is known about the geographical distribution, altitudinal range, and ecological limits of most Brachycephalus species. In this study, we review the available data on the geographical and altitudinal distribution of Brachycephalus based on occurrence records compiled from literature and museums, both for the genus as a whole and separately for the three recently proposed groups of species (ephippium, didactylus, and pernix). The final ensemble dataset comprised 333 records, 120 localities, 28 described species, and six undescribed ones. Species were recorded in six relief units, the richest of which being the Serra do Mar, with 30 species. When the Serra do Mar is subdivided into three subunits, Northern, Central and Southern Serra do Mar, the number of species increase from north to the south, with records of six, nine, and 16 species, respectively. We were able to estimate the extent of occurrence of nearly half of the described species, and the resulting estimates indicate that many of them show remarkably small ranges, some of which less than 50 ha. Brachycephalus species are present from sea level to roughly 1,900 m a.s.l., with the highest richness being found between 751 and 1,000 m a.s.l. (21 spp.). The species with the broadest altitudinal range were B. didactylus (1,075 m) and Brachycephalus sp. 1 (1,035 m), both in the didactylus group, and B. ephippium (1,050 m), of the ephippium group. The broadest altitudinal amplitude for species of the pernix group was recorded for B. brunneus (535 m). The lowest altitudinal records for the pernix group were at 845 m a.s.l. in the state of Paraná and at 455 m a.s.l. in the state of Santa Catarina. The altitudinal occurrence in the pernixspecies group seems to decrease southward. Syntopy between species is also reviewed.

Three New Species of Phytotelm-Breeding Melanophryniscus from the Atlantic Rainforest of Southern Brazil (Anura: Bufonidae)

Three new species of Melanophryniscus are described from the Serra do Mar mountain range of the state of Santa Catarina, southern Brazil. All species are found at intermediate to high altitudes and share phytotelm-breeding as their reproductive strategy. The new species are distinguished from other phytotelm-breeding Melanophryniscus based on different combinations of the following traits: snout-vent length, presence of white and/or yellow spots on forearms, mouth, belly and cloaca, pattern and arrangement of warts, and presence and number of corneous spines. The discovery of these species in a rather restricted geographical area suggests that the diversity of phytotelm-breeding species of Melanophryniscus might be severely underestimated. The conservation status of these species is of particular concern, given that one of them is at risk of extinction not only due to its restricted habitat, but also because of anthropogenic disturbances.

A new species of Brachycephalus (Anura: Brachycephalidae) from the Quiriri mountain range of southern Brazil

A new miniaturized toadled of the genus Brachycephalus (Anura: Brachycephalidae) is described from Serra do Quiriri in the municipality of Campo Alegre, Santa Catarina, southern Brazil. Specimens were collected from the leaf litter between from 1,263 and 1,318 m above sea level. The new species is distinguished from all its congeners by the combination of the following characters: snout–vent length 9.9–13.1 mm; skin on head and dorsum without dermal co-ossification; snout mucronate in dorsal view; dorsum rugose; general color brown, with a narrow orange vertebral stripe. The region where the new species is located is also shared with other endemic anuran species and has experienced strong anthropogenic impacts,suggesting that immediate actions should be taken to ensure their long-term preservation.

Seven new microendemic species of Brachycephalus (Anura: Brachycephalidae) from southern Brazil

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.

Prediction of phylogeographic endemism in an environmentally complex biome

Phylogeographic endemism, the degree to which the history of recently evolved lineages is spatially restricted, reflects fundamental evolutionary processes such as cryptic divergence, adaptation and biological responses to environmental heterogeneity. Attempts to explain the extraordinary diversity of the tropics, which often includes deep phylogeographic structure, frequently invoke interactions of climate variability across space, time and topography. To evaluate historical versus contemporary drivers of phylogeographic endemism in a tropical system, we analyse the effects of current and past climatic variation on the genetic diversity of 25 vertebrates in the Brazilian Atlantic rainforest. We identify two divergent bioclimatic domains within the forest and high turnover around the Rio Doce. Independent modelling of these domains demonstrates that endemism patterns are subject to different climatic drivers. Past climate dynamics, specifically areas of relative stability, predict phylogeographic endemism in the north. Conversely, contemporary climatic heterogeneity better explains endemism in the south. These results accord with recent speleothem and fossil pollen studies, suggesting that climatic variability through the last 250 kyr impacted the northern and the southern forests differently. Incorporating sub-regional differences in climate dynamics will enhance our ability to understand those processes shaping high phylogeographic and species endemism, in the Neotropics and beyond.

Lactate and glucose minimum speeds and running performance

This study aimed to analyse the validity of glucose minimum speed (GMS) for lactate minimum speed (LMS) assessment during running and their relationship to endurance performance. Eight male trained runners (28.7 +/- 9.0 years) volunteered to take part in this study and underwent an official 10-km road race and a track lactate minimum test (LMT) (0.5-km sprint plus 6 x 800 m from 87 to 98% of maximal 3-km speed). Lactate and glucose minimum speeds were considered those related to the minimum blood lactate and glucose concentrations respectively attained during the graded phase of LMT. Significant correlations (p < 0.05) were found between LMS and GMS (r = 0.72) and LMS and 10-km performance (r = 0.83), but not between GMS and 10-km performance (r = 0.49). No significant differences (p > 0.05) were found between LMS (4.75 +/- 0.08 m/s), GMS (4.73 +/- 0.07 m/s) and 10-km mean speed (4.79 +/- 0.17 m/s). In conclusion, we found GMS to be a good predictor of LMS during track LMT, LMS being well related to endurance running performance.