Martín O. Pereyra

Instituto de Biología Subtropical (IBS, CONICET), Universidad Nacional de Misiones (UNaM) Argentina

The Rhinella granulosa group consists of 13 species of toads distributed throughout open areas of South America and Panama. In this paper we perform a phylogenetic analysis considering all but one species of the group, employing five nuclear and four mitochondrial genes, for up to 7910 bp per specimen. Separate phylogenetic analyses under direct op...

Most anurans possess a tympanic middle ear (TME) that transmits sound waves to the inner ear; however, numerous species lack some or all TME components. To understand the evolution of these structures, we undertook a comprehensive assessment of their occurrence across anurans and performed ancestral character state reconstructions. Our analysis ind...

True toads of the genus Rhinella are among the most common and diverse group of Neotropical anurans. These toads are widely distributed throughout South America, inhabiting a great diversity of environments and ecoregions. Currently, however, the genus is defined solely on the basis of molecular characters, and it lacks a proper diagnosis. Although...

Skin glands in amphibians are either distributed throughout the skin or aggregated in multiglandular structures such as the parotoids typical of most species of Bufonidae. Although many early divergent and derived bufonids lack a discrete parotoid in the postorbital-supratympanic (PoSt) region, they have a great macroscopic diversity in the skin mo...

Although studies of anuran hand and foot musculature began in the first half of the 19th century, all studies to date have been taxonomically or anatomically restricted in scope, and none has considered the diversity of autopodial myology in Anura as a whole. As a model for future comparisons, we thoroughly describe the hand and foot musculature of...

In this work, we reanalyzed specimens from Paraguay assigned to the species Rhinella icterica from the departments of Canindeyú and Amambay located in the Cerrado ecoregion. Based on the evaluation of external morphological characters, we conclude that they should be assigned to the species Rhinella cerradensis. On the other hand, we consider that...

The evolution of reproductive strategies depends on the relative balance between current benefits and future costs. Geographic variation in demographic and ecological factors has the potential to affect reproductive strategies by altering this optimal cost-benefit balance. Here, we studied a population of the harvestmen Discocyrtus prospicuus inhab...

Ancestral character-state reconstruction is a powerful method in phylogenetics that can be applied to elucidate the evolutionary history of secondary sexual characters. Here, we surveyed the variation and reconstructed the ancestral states of secondary sexual characters (i.e. sexual dichromatism, vocal slits and nuptial pads) for the most species-r...

The best known Neotropical fossil bufonid discovered to date is described herein. This material includes well-preserved cranial and postcranial disarticulated remains that were part of a microvertebrate fossil assemblage generated by the accumulation of predatory bird pellets. The remains were recovered from the Middle Unit of the Uquía Formation (...

We describe the hand and foot musculature of the fossorial Indian purple frog, Nasikabatrachus sahyadrensis, and compare it to other members of Sooglossoidea: the Seychellean sooglossid genera Sechellophryne and Sooglossus. Due to the key phylogenetic position of Sooglossoidea, we compare its members with the diversity of Anura and define 52 charac...

The eyes of frogs and toads (Anura) are among their most fascinating features. Although several pupil shapes have been described, the diversity, evolution, and functional role of the pupil in anurans have received little attention. Studying photographs of more than 3200 species, we surveyed pupil diversity, described their morphological variation,...

In this work, we show that Bufo levicristatus Boettger, 1885 is a senior synonym of Bufo scitulus Caramaschi & Niemeyer, 2003, and not a junior synonym of Bufo ornatus Spix, 1824, as previously considered. In addition, we present evidence that Bufo scitulus Caramaschi & Niemeyer, 2003 complies with the International Code of Zoological Nomenclature...

The parotoid macrogland in toads of the family Bufonidae is a complex structure mainly related to a defensive function. It presents considerable variability among species regarding their morphology, chemical nature of the glandular content, and secretion release mechanisms. This macrogland is formed by a group of large syncytial glands (LSGs) that...

Anurans show a wide variety of anti-predator mechanisms, and the species of the Neotropical clade Leiuperinae display several of them. Most species of Edalorhina, Physalaemus and Pleurodema show eyespots, hidden bright colours, macroglands in a inguinal/lumbar position, defensive behaviours and/or chemical defence. We conducted a histological analy...

In this paper we present a phylogenetic analysis of the treefrogs of the Boana pulchella Group with the goals of (1) providing a rigorous test its monophyly; (2) providing a test of relationships supported in previous studies; and (3) exploring the relationships of the several species not included in previous analyses. The analyses included more th...

The Rhinella spinulosa group is a clade of toads that inhabit the Andes mountains from northern Ecuador to Patagonia. Its taxonomy was recently revised, and in its new arrangement comprises nine species, including Rhinella gallardoi, traditionally placed in a different intrageneric group. In this work we studied the larval external and internal mor...

The Rhinella granulosa group currently comprises 14 species of Neotropical toads, and its monophyly is strongly supported by several synapomorphies, including a distinctive set of larval characters. Recently, the identities of specimens used in the description of the tadpoles of R. major and R. mirandaribeiroi were questioned. In this work, we revi...

There is a great amount of ecological information for terrestrial arthropods in several types of habitats, but few studies have focused on populations living in tidal freshwater wetlands. During a two-year field survey, we studied the temporal dynamics of the harvestman Discocyrtus prospicuus inhabiting a freshwater wetland exposed to predictable t...

[This corrects the article DOI: 10.1371/journal.pone.0222131.].

Skin glands in amphibians are either distributed throughout the skin or aggregated in multiglandular structures such as the parotoids typical of most species of Bufonidae. Although many early divergent and derived bufonids lack a discrete parotoid in the postorbital–supratympanic (PoSt) region, they have a great macroscopic diversity in the skin mo...

The genus Scinax currently includes more than 120 species, recovered in two major clades, the S. catharinae and the S. ruber clades. The latter comprises 75 species, most of which remain unassigned to any species groups, while 12 are included in the S. rostratus and S. uruguayus groups. In this paper we present a taxonomic review of the two species...

We present a molecular phylogenetic analysis of the hylid tribe Hylini, with the goals of testing the monophyly of the genera Du- ellmanohyla, Isthmohyla, and Ptychohyla and providing a discussion on the monophyly of Bromeliohyla, Charadrahyla, Ecnomiohyla, Exerodonta, Megastomatohyla, and Sarcohyla. Our results indicate the paraphyly of Ptychohyla...

A new species of Physalaemus from Misiones province, Argentina, in the Atlantic forest domain is described. The new species is a member of the P. gracilis group, based on its phylogenetic position and the occurrence of a putative morpho-logical synapomorphy (occurrence of an unpigmented median stripe on throat, chest, and/or abdomen). Physalaemus s...

We studied the foot musculature of the fossorial family Odontophrynidae (composed of the genera Macrogenioglottus, Odontophrynus, and Proceratophrys) plus several outgroup taxa from Hyloidea and other burrowing taxa from across Anura. We found novel character-states supporting the monophyly of Odontophrynus, Proceratophrys, and Odontophry-nus + Mac...

We report a new specimen of Tachymenis chilensis chilensis from Epu Lauquen Natural Reserve, Neuquén, Argentina. This specimen represents the northernmost voucher of T. c. chilensis in Argentina and confirms the presence of the subspecies occupying moist habitats remnants in dry areas of northern Neuquén province. Moreover, this record corresponds...

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009;...

In recent decades, a renewed interest in comparative studies of embryonic ontogeny in anurans is taking place. Toad embryos are often employed as model organisms, and scarce attention has been put on interspecific variations. In this work we analyze the development of transient embryonic and larval structures in 21 species in five genera of Bufonid...

Leech predation on amphibians has been previously reported. Amphibian egg predation has been reported in North and South America, Southeast Asia, Australia, and Europe. Previous reports of anuran eggs being predated by leeches in Argentina include an unidentified Oxyptychus feeding on eggs of Rhinella dorbignyi (Dorbigny's Toad) and Hypsiboas pulch...

Rhinella rumbolli is a poorly known, medium-sized toad endemic to the Yungas of Argentina. Recent fieldwork allowed observing its peculiar oviposition mode, which is described in this paper. A review of literature and examination of museum material indicate that oviposition in Rhinella can vary from strings of eggs in a gelatinous tube (uniserial,...

The horned frog family, Ceratophryidae, currently comprises three genera and 12 extant species, distributed from the Caribbean lowlands to the Pampean grasslands. Horned frogs are fossorial species that are remarkable in terms of their adult and larval morphology, karyotype, behavior, and other aspects of their biology. In this paper we present a m...

We describe the larval morphology of Rhinella azarai, a medium-sized species of the Rhinella granulosa group. None of the morphological characters allow the larvae of R. azarai to be distinguished unequivocally from those of other species in the group. However, the tadpoles show a distinctive set of character states shared with some species of the...

We present a comprehensive review of larval morphology in the Neotropical toad genus Melanophryniscus. The taxa studied included 23 species with representatives of recognized phenetic groups and different larval ecomorphological guilds: pond, stream, and phytotelm-dwelling tadpoles. Their external morphology variation is congruent with current phen...

We describe a new species of Oreobates from Jujuy, Argentina. The new species is clearly diagnosable from other species of Oreobates by a combination of morphological characters and support by molecular evidence (genetic distance and phylogenetic analysis). We also provide taxonomic comments about O. discoidalis and O. barituensis, emphasizing the...

Dendropsophini is the most species-rich tribe within Hylidae with 234 described species. Although cytogenetic information is sparse, chromosome numbers and morphology have been considered as an important character system for systematic inferences in this group. Using a diversity of standard and molecular techniques, we describe the previously unkno...

We compare the advertisement calls of Scinax aromothyella and S. berthae, two closely related Neotropical hylid frogs of the S. catharinae group. We studied several individuals from different localities in Argentina, Brazil and Uruguay. The call parameters analyzed did not allow the discrimination between the two species. Like in other species of t...

We present a cytogenetic survey of the basal bufonid genus Melanophryniscus that covered 14 of the 25 species currently recognized, representing the three phenetic species groups: M. moreirae, M. stelzneri, and M. tumifrons. All species presented a diploid chromosome complement constituted by 11 bi-armed chromosome pairs (2n = 2x = 22; FN = 44). So...

Odontophrynus maisuma is a recently described diploid species of the diploid-tetraploid O. americanus complex. It inhabits coastal regions of Uruguay and southern Brazil. Tadpoles of O. maisuma at stages 33–36 are about 47 mm of total length, and similarly to that of other Odontophrynus are typical pond dwelling anuran larvae; the oral disc is smal...

The frog genus Odontophrynus is a composite of diploid and tetraploid populations and species that are widely distributed in South America. Some of the several genetic studies on this group report the production of artificial hybrids but only a single case of natural hybridization has been documented, in southern Brazil. In this study we report the...

La rana toro Lithobates catesbeianus (Shaw, 1802) [conocida hasta recientemente como Rana catesbeiana (Frost et al., 2006)] es originaria de Norteamérica, con un rango de distribución nativa que comprende la región sudeste de Canadá, este de Estados Unidos y nor-deste de México (Frost, 2004). Esta especie es utilizada frecuentemente en la industria...