Julián Faivovich

• Ph.D.
• Curator at Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"

Of the many features that make frogs and toads unique, vocal sacs are among the most remarkable. Vocal sacs are inflatable, elastic chambers present in adult males of most anurans and are key elements in their social interactions. Traditionally vocal sacs have been associated primarily with acoustic communication, but their functions are currently...

Photoreceptor oil droplets (ODs) are spherical organelles placed most commonly within the inner segment of the cone photoreceptors. Comprising neutral lipids, ODs can be either non-pigmented or pigmented and have been considered optically functional in various studies. Among living amphibians, ODs were only reported to occur in frogs and toads (Anu...

Scinax is the most species-rich genus of Neotropical treefrogs, with 129 currently recognized species divided between two major clades, the S. catharinae and S. ruber clades. The S. catharinae clade includes 52 species currently placed in the S. perpusillus and S. catharinae groups, whereas the S. ruber clade is composed of 77 species, 13 of which...

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...

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 the tadpoles of some anuran species, there is a set of one or more anterior labial tooth rows that are divided by the upper jaw sheath, which we call paraoral tooth rows. We studied the taxonomic distribution of these tooth rows based on published information and preserved specimens in 4,595 species of anurans from all currently recognized famil...

In a recent speech to the UN General Assembly, Argentine President Javier Milei rejected the Pact for the Future and the 2030 Agenda, a comprehensive global framework for sustainable development encompassing ‘people, planet, and prosperity.’ This position undermines Argentina’s capacity to tackle urgent socio-environmental challenges like poverty,...

The casque-headed lophyohyline genus Nyctimantis is widespread in South America, being composed of seven species. A recent molecular and morphological review of the genus found some undescribed species, one of which, from the Brazilian Cerrado, is described in this paper. It is distinguished by its relatively small to medium size, skull without exp...

We describe a new species in the Scinax granulatus group from the Atlantic Forest of northeastern Brazil and include the new species in an updated phylogenetic hypothesis for the group. The new species differs from all other species in the S. granulatus group by a combination of characters, such as a weakly bilobate vocal sac, moderately developed...

The most generalized reproductive mode in anurans is the deposition of egg clutches in water that develop into exotrophic aquatic tadpoles. Yet, despite this extended distribution, cases of parental care on submerged egg clutches are poorly documented. Because of its high diversity, its aquatic habits, and reports on males of two species standing n...

Ololygon skuki is a species of the O. argyreornata group, only known to occur in an Atlantic Forest fragment in the state of Alagoas, Brazil. Current knowledge about this species is restricted to descriptions of both adults and larvae. In this study, we explore the phylogenetic relationships of O. skuki based on molecular data, provide new morpholo...

Isthmohyla insolita and Exerodonta catracha are Honduran hylids of uncertain phylogenetic relationships. In this paper we present a phylogenetic analysis of mitochondrial and nuclear genes to study their relationships. Our results show that these species are, respectively, the sister taxon of and nested among the few available species of Plectrohyl...

The genus Aplastodiscus (Hylidae) is widely distributed in the Atlantic Forest of Brazil and adjacent Argentina, and a single species inhabits the Cerrado in Central Brazil. The genus comprises 16 species included in 4 species groups. The A. albosignatus species group contains 6 described species, as well as two candidate species referred to as Apl...

We describe a new species of the Scinax cruentomma species group, with a red streak in the iris and a weakly bilobate vocal sac. It is known from oligotrophic soils in the sedimentary basin of the Ucayali River near Jenaro Herrera (province of Requena, Peru) and Río Blanco (buffer zone of the Matses Indigenous territory and reserve). The new specie...

Natural history museums are vital repositories of specimens, samples and data that inform about the natural world; this Formal Comment revisits a Perspective that advocated for the adoption of compassionate collection practices, querying whether it will ever be possible to completely do away with whole animal specimen collection.

Anuran skin is a dynamic organ involved in essential functions that strongly correlate with specific morphological traits. Particularly, gas exchange has been associated with epidermal modifications, such as reduced cell layers and increased vascularization. Here, we describe the epidermal morphology and its association with capillary networks in t...

‘Rewilding’ is a nature conservation strategy gaining prominence worldwide. Established in the Northern Hemisphere, rewilding initiatives have increasingly been proposed in Argentina, but their relative merits, feasibility of implementation and accountability have lacked adequate analysis and discussion. Recently, 125 scientists and practitioners w...

Biography of Juan R. León-Ochoa

The Pehuenche Spiny-chest Frog (Alsodes pehuenche) is a nocturnal aquatic frog that inhabits small streams and wetlands in the Central Andean Cordillera near the border between Argentina and Chile. The International Union for Conservation of Nature (IUCN) classified it as Critically Endangered (CR) due to its small extent of occurrence (EOO) and ar...

En los últimos años se han desarrollado en Argentina distintas intervenciones relacionadas con el rewilding (o re-asilvestramiento), abarcando una variedad de especies (e.g., grandes carnívoros, ungulados, psitácidos) y ecorregiones (e.g., Chaco Húmedo y Seco, Estepa Patagónica). El reasilvestramiento es definido como una estrategia aplicada en el...

Book Review

Amphibians have a great diversity of bioactive peptides in their skin. The cDNA prepro-peptide sequencing allowed the identification of five novel mature peptides expressed in the skin of Boana pulchella, four with similar sequences to hylin peptides having a cationic amphipathic-helical structure. Whole mature peptides and some of their fragments...

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...

We describe the larval morphology of the stream-dwelling tadpole of Hyloscirtus antioquia based on specimens from the type locality, Antioquia, Colombia. The larvae of H. antioquia (belong to the suctorial ecomorphological guild) show morphological characters commonly associated with lotic habitats, like a depressed body, low fins, long tail, well-...

The hands of adult males of many dendrobatid poison frogs and their relatives possess swelling formed by glandular tissue hypothesized to secrete courtship pheromones delivered to the female during cephalic amplexus. Variation in the occurrence and external morphology of the swelling of finger IV has provided important evidence for dendrobatoid sys...

Several species of Cophomantini are known to have an enlarged prepollex, commonly modified as an osseous spine. We surveyed the osteology and myology of the prepollex and associated elements of 94 of the 190 species of Cophomantini, sampling all genera, except Nesorohyla. Two distinct prepollex morphologies were found: a bladeshaped and a spine-sha...

For almost 30 years, there have been active discussions about the taxonomic impediment and the challenge this represents to address the current human-induced biodiversity crisis. From the start (Systematics Agenda 2000, 1994), the term ‘taxonomic impediment’ has been ambiguous, designating both the insufficiency and inadequacy of the resources put...

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,...

Vocal sacs are among the most conspicuous features of anurans and are particularly striking in casque-headed treefrogs (Hylidae: Hylinae: Lophyohylini) with their wide array of morphologies. In this paper, we assessed the anatomy of vocal sacs in representatives of the Lophyohylini, described eight discrete characters, and studied their evolution....

Vocal sacs are among the most conspicuous features of anurans and are particularly striking in casque-headed treefrogs (Hylidae: Hylinae: Lophyohylini) with their wide array of morphologies. In this paper, we assessed the anatomy of vocal sacs in representatives of the Lophyohylini, described eight discrete characters, and studied their evolution....

The most ventral muscles of the head (the mm. submentalis, intermandibularis, and interhyoideus) provide support to the gular region and lift the buccal floor during ventilation and feeding. These muscles show limited variation in most gnathostomes, but in Anura they exhibit a surprising diversity. The few studies that have explored this character...

Anurans have the greatest diversity of reproductive modes among tetrapod vertebrates, with at least 41 being currently recognized. We describe a new reproductive mode for anurans, as exhibited by the Paranapiacaba Treefrog, Bokermannohyla astartea, an endemic and poorly known species of the Brazilian Atlantic Forest belonging to the B. circumdata g...

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...

The light that emerges from a biological entity is relevant from many aspects. In the first place, it allows the construction of the organism’s image and consequently it is responsible for visual perception and communication. Secondly, it can become an important tool in obtaining both physiological and chemical information from the observed entity,...

We report recent findings of Isthmohyla pictipes (Cope, 1875) in the Cordillera de Talamanca, Costa Rica, roughly two decades after it was last registered. We provide notes on microhabitat use, color variation, external morphology of adults and larvae, and geographic variation, and discuss some taxonomic characters employed to differentiate I. pict...

The uncertain identity of Hyla x-signata Spix, 1824 has been a pervasive problem in the taxonomy of the genus Scinax. A species supposedly distributed from northeastern Brazil northwards to Colombia and Venezuela, described in a few lines without much information and with an accompanying figure, and its type specimen lost during World War II, combi...

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 relationships of the hyline tribe Dendropsophini remain poorly studied, with most published analyses dealing with few of the species groups of Dendropsophus. In order to test the monophyly of Dendropsophini, its genera, and the species groups currently recognized in Dendropsophus, we performed a total evidence phylogenetic analysis. The molecul...

Many vertebrates have distinctive blue-green bones and other tissues due to unusually high biliverdin concentrations—a phenomenon called chlorosis. Despite its prevalence, the biochemical basis, biology, and evolution of chlorosis are poorly understood. In this study, we show that the occurrence of high biliverdin in anurans (frogs and toads) has e...

The two species of the Bokermannohyla claresignata species group (Anura: Hylidae) have not been collected for the last four decades. It is the only species group of the hyline tribe Cophomantini that has not yet been analysed genetically. Its phylogenetic position is thus uncertain, and it has a combination of adult and larval character states that...

The two species of the Bokermannohyla claresignata species group (Anura: Hylidae) have not been collected for the last four decades. It is the only species group of the hyline tribe Cophomantini that has not yet been analysed genetically. Its phylogenetic position is thus uncertain, and it has a combination of adult and larval character states that...

The hyline tribe Lophyohylini includes 87 species of treefrogs, of which cytogenetics aspects have been studied in less than 20% of them. In order to evaluate the evolution of some of its chromosome characters (NOR position, C-bands, and DAPI/CMA3 bands), we studied the karyotypes of 21 lophyohylines, 16 of them for the first time, and analyzed the...

A recent publication reported the Atlantic Forest endemic hylid Trachycephalus mesophaeus for the Chacoan ecoregion in Argentina. In this paper, we analyzed the voucher specimen and showed that it is a misidentified specimen of the Asiatic microhylid Kaloula pulchra, a species commonly commercialized in the pet trade worldwide. Therefore, there is...

The world of Marcos Abraham Freiberg (1911-1990): herpetologist and popularizer of zoology in Argentina. This article reviews the biography and the contributions of Marcos Abraham Freiberg (1911-1990), emblematic figure of the popularization of zoological diversity in Argentina. His herpetological work is reviewed, as well as his contributions to e...

The South American and West Indian Casque-headed Treefrogs (Hylidae: Hylinae: Lophyohylini) include 85 species. These are notably diverse in morphology (e.g. disparate levels of cranial hyperossification) and life history (e.g. different reproductive modes, chemical defences), have a wide distribution, and occupy habitats from the tropical rainfore...

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

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...

Hyla varelae Carrizo, 1992 is an Argentinean species only known from the holotype. The study of this specimen indicates that it pertains to the Boana pulchella group and it is a junior synonym of Hyla riojana Koslowsky, 1895 (currently Boana riojana). We traced the itinerary of the field trip in which the holotype was collected using the catalog of...

We describe a new species of the Scinax catharinae group from the highlands of the State of Santa Catarina, southern Brazil. The new species is distinguished from the other species of the group for having a trapezoid interocular blotch, an externally distended vocal sac, hypertrophied forearms in males, and the extension of foot webbing on Toe V. T...

Vocal sacs are present in most species of frogs and are the product of the interaction of three elements: the gular skin, the superficial submandibular musculature and an internal mucosa derived from the buccal floor. In this paper, we surveyed the structural diversity in the vocal sac of microhylids and related families in 109 exemplar species, in...

Secondary sexual characters form a diverse group of traits widely spread in amphibians. Within anurans, the Hylini tribe represents an interesting group to examine the evolution of this type of characters because it has different skin structure modifications, including ventrolateral glands, nuptial pads, and unique swollen upper lips. We analysed t...

Cascades and fast-flowing streams impose severe restrictions on acoustic communication, with loud broadband background noise hampering signal detection and recognition. In this context, diverse behavioural features, such as ultrasound production and visual displays, have arisen in the evolutionary history of torrent-dwelling amphibians. The importa...

Cascades and fast-flowing streams impose severe restrictions on acoustic communication, with loud broadband background noise hampering signal detection and recognition. In this context, diverse behavioural features, such as ultrasound production and visual displays, have arisen in the evolutionary history of torrent-dwelling amphibians. The importa...

The Neotropical hylid genus Sphaenorhynchus includes 15 species of small, greenish treefrogs widespread in the Amazon and Orinoco basins, and in the Atlantic Forest of Brazil. Although some studies have addressed the phylogenetic relationships of the genus with other hylids using a few exemplar species, its internal relationships remain poorly unde...

The non-monophyly of both the genus Myersiohyla and the Boana punctata group has been recovered in a number of published phylogenetic analyses. In this paper we report on the analysis of sequences of Boana liliae, a species originally assigned to the B. punctata group, in a dataset of Cophomantini that recovered novel phylogenetic relationships for...

The non-monophyly of both the genus Myersiohyla and the Boana punctata group has been recovered in a number of published phylogenetic analyses. In this paper we report on the analysis of sequences of Boana liliae, a species originally assigned to the B. punctata group, in a dataset of Cophomantini that recovered novel phylogenetic relationships for...

The nuptial pad is a secondary sexual character found in anuran amphibians. It includes modified epidermal and dermal tissues and is usually located on the first digit of the hand of males. In this study, we review the structure and diversity of nuptial pads based on a large-scale sample of morphological and phylogenetic diversity. Our findings sho...

Peptides from skin secretions of amphibians are considered important components of their immune system and also play a relevant role in their defense mechanism against predators. Herein, by using mass spectrometry (MS), we characterize the sequence of 13 peptides from the gland secretion of the hylid tree frog, Boana punctata. Using in situ matrix-...

The nuptial pad is a secondary sexual character found in anuran amphibians. It includes modified epidermal and dermal tissues and is usually located on the first digit of the hand of males. In this study, we review the structure and diversity of nuptial pads based on a large-scale sample of morphological and phylogenetic diversity. Our findings sho...

Sphaenorhynchus platycephalus was briefly described on the basis of a single specimen, with only “S‑Amerika” as its locality. Although it has been regarded as a distinct species, compelling evidence is lacking. A comparison of all currently described species of Sphaenorhynchus, including type specimens of several species, allowed us to provide morp...

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...

The hylid tribe Cophomantini is a diverse clade of Neotropical treefrogs composed of the genera Aplastodiscus, Boana, Bokermannohyla, Hyloscirtus, and Myersiohyla. The phylogenetic relationships of Cophomantini have been comprehensively reviewed in the literature, providing a suitable framework for the study of chromosome evolution. Employing diffe...

Information of the specimens analyzed of each species. (PDF)

Cytogenetic information in Cophomantini. Differential techniques performed, chromosome number (2n) and NORs position observed in each species. (PDF)

Chromosome measurements of 25 species of Boana and 3 of Hyloscirtus. (a) B. albopunctata group; (b) B. faber group; (c) B. pellucens group; (d) B. pulchella group; (e) B. punctata group; (f) B. semilineata group. (B) B chromosome in B. leucocheila. Chromosome percentage relative to the haploid set (Chromosome Mophology) Centromeric Index ± Standard...

Optimization of the basic number (X) and the position of NORs (NORs) in Cophomantini on the phylogenetic hypothesis of Duellman et al. (2016). (PDF)

DAPI and CMA3 staining in 20 species of Boana. The square shows heteromorphic NOR-bearing chromosome pair in B. punctata sequentially stained by the silver impregnation technique. (TIF)

Anuran vocal sacs are elastic chambers that recycle exhaled air during vocalizations and are present in males of most species of frogs. Most knowledge of the diversity of vocal sacs relates to external morphology; detailed information on internal anatomy is available for few groups of frogs. Frogs of the family Hylodidae, which is endemic to the At...

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...

In this paper we present information on fluorescent frogs that will be of use to interested researchers. We describe practical details and provide new data on the phenomenon in Boana punctata, while reporting for the first time its occurrence in the closely related B. atlantica. Both species leave persistent fluorescent marks on the substrate in fi...

Significance In this interdisciplinary study, we report naturally occurring fluorescence in amphibians; specifically, in a common South American tree frog. We show that fluorescence is traceable to a class of compound that occurs in lymph and skin glands. Our study indicates that in our model species, in low-light conditions, fluorescence accounts...

Among anuran embryonic structures, the adhesive (cement) glands appear posterolaterally to the stomodeum and produce a mucous secretion that adheres embryos to surfaces in and out of the egg. In this paper, we study the ontogeny of the adhesive glands in five species of Phyllomedusa representing the two main clades recognized in the genus, plus emb...

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;...