Francisco Kolenc

Museo Nacional de Historia Natural, Montevideo, Uruguay · Sección Herpetología

The amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd) causes chytridiomycosis, a disease among the main causes of amphibian declines worldwide. However, Bd studies on Neotropical amphibians from temperate areas are scarce. We present a comprehensive survey of Bd in Uruguay, in temperate central eastern South America, carried out between...

We review the taxonomy of two historically problematic taxa of Neotropical frogs belonging to the Physalaemus cuvieri group: P. albonotatus and P. cuqui. A thorough revision of morphological, bioacoustic, cytogenetic, and genetic characters throughout their ranges indicated that P. cuqui is a junior synonym of P. albonotatus. In addition, our analy...

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...

We studied in this work the skin healing process in the terrestrial toad Melanophryniscus montevidensis. Wild specimens were acclimated in the laboratory, and an experimental skin wound of 1.5 mm diameter was made in the dorsum region under clove oil anesthesia, leaving the dermis exposed. Monitoring of the healing process by conventional histology...

Caiman latirostris is a Neotropical crocodilian for which there is scarce natural history information in regard to other species, as also about survey methods used by field researchers. In this work we report the capture methodology implemented during population monitoring in northern Uruguay and some observations about defensive and feeding behavi...

The holotype of Odontophrynus americanus collected by Alcide d'Orbigny in northern Patagonia, Argentina differs morphologically from the tetraploid frogs repeatedly assigned to this species and that are distributed from central Argentina and Uruguay to the north to Brazil and Paraguay (probably also Bolivia). Surprisingly, the external characterist...

Intending to increase the knowledge about cytogenetics of Physalaemus and the sparsely studied P. gracilis group, we analyzed the karyotypes of P. carrizorum, P. gracilis, P. lisei, and P. sp. aff. gracilis. We studied chromosome morphology, heterochromatin patterns, Ag-NORs location and mapped the repetitive DNA sequence PcP190. All species showed...

This study reviews the geographic distributions of four hylid frogs native to Uruguay: Dendropsophus nanus, D. minutus, Lysapsus limellum, and Scinax nasicus. Their current conservation status in Uruguay, according to the IUCN red listing criteria, is Endangered, as few locality records were available and published in the herpetological literature...

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...

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...

The criteria used by previous authors to define colour aberrancies of snakes, particularly albinism, are varied and terms have widely been used ambiguously. The aim of this work was to review genetically based aberrant colour morphs of wild Neotropical snakes and associated terminology. We compiled a total of 115 cases of conspicuous defective expr...

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

A new species of Leptodactylus frog (Anura: Leptodactylidae) from the South American Gran Chaco, morphologically similar and previously confused with the widespread Leptodactylus mystacinus, is described through the use of multiple sources of evidence (molecular, external morphology, coloration, osteology, bioacoustics, and behavior). The phylogene...

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...

The study of early development in Neotropical Leiuperinae frogs (Anura, Leptodactylidae) has been addressed by several works in recent times. However, a comparative developmental approach under a phylogenetic context was not available. Herein we analyzed the morphological and ontogenetic diversity of embryos belonging to 22 species of the three lar...

Histology is often underappreciated for the detection of the amphibian pathogenic fungus Batrachochytrium dendrobatidis, the cause of the potentially lethal skin disease chytridiomycosis. We evaluated the sensitivity of histology to detect chytrids in 20 wild specimens of 2 frog species from Uruguay that were clinically normal, but confirmed by PCR...

We report a case of nasal rhinosporidiosis in a dog native to Uruguay, being the sixth report of Rhinosporidium seeberi infection in this host from South America. Diagnosis was made by histopathology of biopsied tissue and specific PCR assay from nasal swab material. The patient was a 3-year-old male dog, of the Dogo Argentino breed, living in a ru...

We communicate the finding of a subcutaneous neoplasia in a female specimen of the toad Melanophryniscus montevidensis (Bufonidae) from Uruguay. The lesion extended from the cephalic to the abdominal region, and both gross and microscopic features were typical of lipomas. This is to our knowledge the fourth case reported in amphibians.

We studied in this work the prevalence of two eukaryotic skin pathogens in a population of the frog Boana pulchella (Anura, Hylidae) from southeastern Uruguay, the fungus Batrachochytrium dendrobatidis (Rhizophydiales) and the protoctistan Valentines rwandae (Ichthyosporea, Der-mocystida), between 2012 and 2014. In both cases higher prevalences wer...

Amphibian parasites of the Order Dermocystida (Ichthyosporea) are widespread pathogens known mainly from Europe and North America, which cause primarily a disease of skin and subcutaneous tissue in their hosts. The taxonomy of these organisms has been problematic given their conserved morphology, similar clinical disease and pathology. Currently re...

Observations on stereotyped defensive behaviours are presented for 7 frog species of the Neotropical genus Odontophrynus from Argentina and Uruguay. Seven stereotyped postures were observed, among which the most common observed were puffing up the body, contracting, and crouching down. Newly reported behaviours include tongue protrusion, eye protec...

In a recent work, Ohler and Dubois (2018) discussed the correct application of Article 23.9 of the Code (Anonymous, 1999; 2012) and illustrated it with some concrete cases in which the authors considered that the Article was misinterpreted. Article 23.9 of the Code allows the “reversal of precedence”, that is, that when a senior homonym or synonym...

Research concerning the early development of anuran tadpoles has sparked new interest, ever since comparative studies revealed structural and temporal variations of embryonic stages within different taxonomic groups. In this paper we studied the early ontogeny of five species of the hylid genus Hypsiboas: H. curupi, H. pulchellus, H. riojanus and H...

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...

We describe the chromosome morphology, C-bands, NORs position, and DAPI/CMA3 staining of five species of Pseudopaludicola (P. boliviana, P. canga, P. falcipes, P. mystacalis, and P. ternetzi) from several populations from Argentina, Brazil, Paraguay, and Uruguay. In addition, the telomeric sequence locations of P. mystacalis and P. canga are evalua...

We report the first record of parasitic larval tapeworms of the genus Spirometra (sparganum) in the frog Hypsiboas pulchellus. A total of 139 frogs were collected in Uruguay, and two of them presented a single sparganum (1.4%). One sparganum was found free into the coelomic cavity, and the other was located under the skin and in the coelomic cavity...

We report infection by Ichthyophonus sp. in a South American amphibian, the hylid frog Hypsiboas pulchellus in Uruguay. This frog had a large subcutaneous mass over the urostyle and dorsal musculature comprised of parasitic cysts with mild granulomatous inflammation but otherwise appeared healthy.

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 the external morphology, buccal cavity, chondrocranium, hyobranchial skeleton, and musculature of the tadpole of Rhinella achavali (Achaval’s Toad), along with its karyotype. Tadpoles were found in a small, permanent stream and were showing schooling behavior. The characterization of the proposed species groups within Rhinella cannot be...

abstract : We present gross and histologic evidence of coinfection in amphibians by fungal-like parasites of the order Dermocystidia (Amphibiocystidium sp.) and the fungus Batrachochytrium dendrobatidis. The condition was observed in frogs Hypsiboas pulchellus (Hylidae) from Uruguay in 2009 to 2012. This report is the first of dermocystids in Neotr...

We present herein observations on A. darwinii made from 2008 to 2011 as part of herpetofaunal inventories in southern Uruguay. Some voucher specimens were accessioned at the herpetological collection of Museo Nacional de Historia Natural, Montevideo, Uruguay (MNHN). Specimens of Amphisbaena darwinii were found under stones or abandoned pieces of co...

The main goal of this manuscript is the reevaluation of the taxonomic status of the teiid lizard Contomastix charrua, known only from Cabo Polonio, a small coastal rocky outcrop in southeastern Uruguay. This species was erected on the basis of the presence of a second pair of ceratobranchials and longer cornua in the hyoid bone, in addition to a re...

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...

Melanophryniscus orejasmirandai is a species of toad known only from two localities in southern Uruguay. This toad is the southernmost suggested taxon of the M. tumifrons group, whose species are characterized by a glandular frontal swelling on the snout. The study of the type series of M. orejasmirandai and of M. pachyrhynus, along with observatio...

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...

Eupemphix fuscomaculatus Steindachner, 1864 was described on the basis of a single specimen collected at Caiçara, Mato Grosso, Brazil. This species, currently included in the genus Pleurodema, experienced a confusing taxonomic history and is supposedly known only from the holotype and seven specimens from Río Apa, Paraguay, collected by Alfredo Bor...

We present an annotated list of the herpetofauna at the Protected Area Quebrada de los Cuervos, Departamento de Treinta y Tres, Uruguay. We recorded 24 species of amphibians and 29 of reptiles, accounting for near half of the species already reported from Uruguay. New records of Dendropsophus minutus (Hylidae) and Liophis almadensis (Colubridae) ar...

The Rhinella granulosa group currently includes 12 species distributed eastern to the Andes, from Panama to central Argentina. We studied bioacoustic features of the advertisement calls in seven of these species: Rhinella azarai, R. bergi, R. centralis, R. dorbignyi, R. fernandezae, R. major, and R. merianae. In addition, we analyzed the release ca...

The oral apparatus of anuran tadpoles is a unique structure composed of soft and keratinized parts surrounding the mouth. Among the many variations, a common oral apparatus involves a dorsal gap in the marginal papillae, keratinized jaw sheaths, and two upper and three lower rows of labial teeth. In Leiuperidae, besides this generalized morphology,...

The hylid frog genus Scinax is the most species-rich within Hylinae, with more than 100 recognized species grouped in the S. catharinae and S. ruber clades. The karyotypes of 14 species of the S. catharinae clade and 14 of the S. ruber clade were analyzed, several of them for the first time. All studied species presented 2n = 2x = 24 biarmed chromo...

We studied the oral apparatus, buccal cavity and musculoskeletal features in tadpoles of five species of the genus Scinax (S. acuminatus, S. uruguayus, S. aff. pinima, S. aromothyella, and S. berthae). Observed variation is mainly related to intrageneric grouping. Scinax acuminatus (S. ruber clade, sister taxon of S. rostratus group) has a distinct...

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 native species of amphibians and reptiles of Uruguay were categorized according to the IUCN Red List criteria. Out of 47 amphibian species, seven are listed as Critically Endangered (CR), five as Endangered (EN), one as Vulnerable (VU), three as Near Threatened (NT), and two as Data Deficient (DD); the remaining species are considered to be Lea...

In this work, we studied chromosome morphology, Ag-NOR, and C-banding patterns in the Neotropical leiuperid frogs that compose the Physalaemus henselii species group: Physalaemus fernandezae, Physalaemus henselii, and Physalaemus riograndensis. The chromosome diploid complement in all species was 2n  =  22 and consisted of seven large to medium and...

Los estudios sobre demografía de crocodilianos en ambientes antropizados son escasos, particularmente en la Región Neotropical. Este trabajo aporta los primeros datos sobre abundancia y estructura poblacional de un caimán neotropical, Caiman latirostris, en hábitats alterados del noroeste de Uruguay (30°S, 57°W). Se realizaron muestreos nocturnos d...

Amphibian chytridiomycosis caused by Batrachochytrium dendrobatidis is reported in Uruguayan native amphibians for the first time. Histological evidence of infection was observed in tadpoles of Hypsiboas pulchellus, Odontophrynus maisuma, Physalaemus henselii, and Scinax squalirostris. The effects of chytridiomycosis on these species are still unkn...

The food habits of the Broad‐snouted Caiman (Caiman latirostris) were studied in northwestern Uruguay. The most common prey were insects, the shrimp Pseudopalaemon bouvieri, the snail Pomacea canaliculata, fish and birds. Spiders, crabs, amphibians, snakes, turtles and mammals were consumed less frequently. Arthropods were the most frequent prey fo...

Pleurodema bibroni and P. kriegi are poorly known species with a troublesome taxonomic history. They are cryptic taxa, currently considered as valid species on the grounds of biogeographic and ecological differences. The first is known from much of southern Uruguay and from the northeastern region of the State of Rio Grande do Sul, Brazil (from sea...

Pleurodema bibroni and P. kriegi are poorly known species with a troublesome taxonomic history. They are cryptic taxa, currently considered as valid species on the grounds of biogeographic and ecological differences. The first is known from much of southern Uruguay and from the northeastern region of the State of Rio Grande do Sul, Brazil (from sea...

FIGURE 6. Habitat of Pleurodema bibroni at the Department of Rocha, Uruguay: (A) flooded grassland with palm trees (Butia capitata) and (B) sandy coastal grassland close to the Atlantic shoreline, where tadpoles were found. Habitat of Pleurodema kriegi at Pampa de Achala, Province of Córdoba, Argentina (C) and pond inhabited by tadpoles of this spe...

FIGURE 7. Defensive behavior of some species of Pleurodema. Pleurodema bibroni (A) emerging from the ground covered with sand, (B) death feigning with limbs outstreched, (C) deimatic behavior, with exposition of lumbar glands and flash coloration and (D) body tilting towards a disturbing stimulus. Deimatic behavior in (E) Pleurodema bufoninum (note...

FIGURE 2. Tadpole of Pleurodema bibroni (stage 35) from Barra de Valizas, Department of Rocha, Uruguay (MNHN 7167), in lateral (A) and dorsal (B) views, and tadpole of Pleurodema kriegi (stage 36) from Parador El Cóndor, Pampa de Achala, Province of Córdoba, Argentina (MLP DB 5059), in lateral (C) and dorsal (D) views. Scale bars = 5 mm.

FIGURE 1. (A) Pleurodema bibroni, Barra de Valizas, Department of Rocha, Uruguay. (B) Pleurodema kriegi (MLP. A 3528), Pampa de Achala, Province of Córdoba, Argentina.

FIGURE 3. (A) Oral disc of a tadpole of Pleurodema bibroni (stage 35) from Barra de Valizas, Department of Rocha, Uruguay (MNHN 7167). (B) Oral disc of a tadpole of Pleurodema kriegi (stage 36) from Parador El Cóndor, Pampa de Achala, Province of Córdoba, Argentina (MLP DB 5059). Scale bars = 1 mm.

FIGURE 4. Advertisement call of Pleurodema bibroni (A) from Barra de Valizas, Department of Rocha, Uruguay (MNHN 7169, water temperature 16 ºC, air temperature 14 ºC), and Pleurodema kriegi (B) from Pampa de Achala, Province of Córdoba, Argentina (MLP. A 3526, water temperature 11 ºC, air temperature 8.5 ºC). Oscillogram (top) and sonogram (center)...

FIGURE 8. (A) Historical geographic distribution of Pleurodema bibroni (closed circles) and Pleurodema kriegi (open circles), based on specimens deposited in collections (see Appendix 1) and literature data (see text). (B) Current known distribution of P. bibroni in Uruguay, based on specimens collected in the last ten years deposited in collection...

We studied the external and oral cavity morphology of the tadpoles of eight species of Hypsiboas in the H. albopunctatus, H. faber, H. punctatus and H. pulchellus species groups. After a review of the available information about larval external and oral cavity morphology, no character state seems to be synapomorphic for Hypsiboas. The presence of a...

Physalaemus henselii (Peters, 1872) is a little known leiuperid frog that has not been studied since the 1960's. Herein, we redescribe its advertisement call, and assess the female sexual cycle and the reproductive period on the basis of the macroscopic analysis of the ovaries and field observations. The Ovarian Size Factor (OSF) was calculated. Th...

We describe the tadpole of Scinax aromothyella from the surroundings of Quebrada de los Cuervos, Departamento de Treinta y Tres, Uruguay. It shares with other larvae of the Scinax catharinae clade the slightly depressed body, a dextral vent tube that reaches the free margin of the ventral fin, and the oral disc with a dorsal gap in the marginal row...

In this work the tadpoles of the neotropical frogs Leptodactylus latinasus, Physalaemus biligonigerus and Physalaemus riograndensis are redescribed. Relevant features of L. latinasus tadpoles are a medial vent tube, labial tooth row formula (LTRF) 2(2)/3(1), and oral disc with a single row of marginal papillae interrupted by a dorsal gap, similarly...

In this work the tadpoles of the neotropical frogs Leptodactylus latinasus, Physalaemus biligonigerus and Physalaemus riograndensis are redescribed. Relevant features of L. latinasus tadpoles are a medial vent tube, labial tooth row formula (LTRF) 2(2)/3(1), and oral disc with a single row of marginal papillae interrupted by a dorsal gap, similarly...

Populations of Caiman latirostris are known to occur in Uruguay but their geographic distribution remains uncertain. This work presents anupdate of the species distribution and conservation status in Uruguay. Surveys conducted by the authors confirmed the presence of this species in the previously known distribution range of northwestern Uruguay, w...

Although Physalaemus frogs are prominent members of Neotropical herpetofauna, larval stages are not known from more than half of the species in this genus. Herein, we describe the tadpole of Physalaemus henselii based on samples collected in Departamento de Rivera, northern Uruguay. General aspect and major external morphological features are simil...

Chaunus dorbignyi and Chaunus fernandezae are the southernmost taxa of the Chaunus granulosus species group (formerly Bufo granulosus group). The biology of these species has been scarcely studied. In this sense, larval external morphology of Chaunus dorbignyi is described for the first time and compared with other species of the granulosus group,...