Raul Maneyro

Universidad de la República de Uruguay | UdelaR · Faculty of Sciences

Picloram (PIC) is an herbicide widely used in Uruguay to control weeds, especially in forest crops. In the present study, we evaluate the acute toxicity and genotoxicity of formulated 24.9% PIC-based Tordon®24K on Boana pulchella tadpoles under standard laboratory conditions. In the acute toxicity test we use mortality as the endpoint and we obtain...

Dendropsophus minutus is a hylid widely distributed in the Neotropics. Although this species is classified as "least concern," some populations are being affected by the advance of various anthropic activities. Despite previous studies on the biology of the species, some aspects of its trophic ecology are still unknown. We used stomach content anal...

Dendropsophus minutus is a hylid widely distributed in the Neotropics. Although this species is classified as «least concern», some populations are being affected by the advance of various anthropic activities. Despite previous studies on the biology of the species, some aspects of its trophic ecology are still unknown. We used stomach content anal...

La rana toro –Aquarana catesbeiana– fue introducida voluntariamente en Uruguay en 1986 con fines de cría para consumo humano. Su producción en cautiverio no fue viable económicamente y el abandono de la producción promovió la liberación accidental o deliberada de diversos ejemplares. Estos organismos llegaron a ambientes naturales y seminaturales,...

Background Experts use knowledge to infer the distribution of species based on fuzzy logical assumptions about the relationship between species and the environment. Thus, expert knowledge is amenable to fuzzy logic modelling, which give to propositions a continuous truth value between 0 and 1. In species distribution modelling, fuzzy logic may also...

Acute toxicity and genotoxicity of the S-metolachlor-based herbicide Dual Gold ® on Leptodactylus luctator (Hudson, 1892) tadpoles (Anura: Leptodactylidae). Herbicides used in agriculture and their metabolites are frequently detected in surface water bodies, where they can persist and cause adverse effects on aquatic organisms. The aim of this stud...

Herbicides used in agriculture and their metabolites are frequently detected in surface water bodies, where they can persist and cause adverse effects on aquatic organisms. The aim of this study was to evaluate the acute toxicity and genotoxic effects of the S-metolachlor (SM)-based herbicide Dual Gold® (DG®), on Leptodactylus luctator tadpoles (An...

The globally invasive Argentine ant (Linepithema humile) possesses a venom lethal to some amphibian species in the invaded range. To test the novel weapons hypothesis (NWH), the effects of the toxin on the cohabiting amphibian species in the ant’s native range need to be investigated. The invader should benefit from the novel chemical in the invade...

Knowledge on biodiversity is fundamental for conservation strategies. The Brazilian Pampa region, located in subtropical southern Brazil, is neglected in terms of conservation, and knowledge of its biodiversity is fragmented. We aim to answer the question: how many, and which, species occur in the Brazilian Pampa? In a collaborative effort, we buil...

Abstract. La desaparición de especies debido a la actividad antrópica es una realidad que afecta a la biodiversidad de todo el planeta. La Lista Roja de Aves del Uruguay, utilizando criterios de la UICN, considera 45 especies de aves amenazadas en nuestro territorio. Para conservar las especies, es necesario conocer y preservar sus áreas de distrib...

Intersexual morphological differences within a species occur in many traits, including body size and shape. Many processes that cause geographic variability in morphology have been proposed: population structure, phenotypic plasticity (environmental effects on development), and natural and/or sexual selection. Several hypotheses can explain pattern...

The uneven spatial distribution of biodiversity is a defining feature of nature. In fact, the implementation of conservation actions both locally and globally has progressively been guided by the identification of biodiversity ‘hotspots’ (areas with exceptional biodiversity). However, different regions of the world differ drastically in the availab...

Little consensus exists on the role of food partitioning in the organization of tadpole assemblages. We studied trophic ecology of syntopic tadpoles through the analysis of gut contents, selectivity, and stable isotopes to assess the occurrence of food partitioning in tadpole assemblages. Tadpoles (n = 194) were collected in three wetlands and corr...

Population declines are noticeable when adults disappear locally or massive die-offs are reported. However, populations can slowly decline if recruitment is unsuccessful. We aimed to determine the recruitment rates and the biotic factors involved in the metamorphosing success of a threatened species, Melanophryniscus montevidensis. Using in situ en...

Lambert et al . question our retrospective and holistic epidemiological assessment of the role of chytridiomycosis in amphibian declines. Their alternative assessment is narrow and provides an incomplete evaluation of evidence. Adopting this approach limits understanding of infectious disease impacts and hampers conservation efforts. We reaffirm th...

Density has been proposed as a factor that could determine larval growth in anurans. We studied such effects on Boana pulchella. After hatching, we reared the tadpoles during 90 days and 93 tadpoles with similar size and developmental stages were chosen. We placed them in 800 cm3 cans with declorified water at five densities (1, 2, 4, 8 and 16 indi...

We present a list of amphibian species from the protected area Barra de la Laguna de Rocha (BLR), Uruguay. Fifteen monthly three-day field trips were performed between September 2011 and March 2013. During each field trip, active searches of individuals and auditive samplings were performed at seven selected sites. We recorded 19 species of amphibi...

Table S1. Detail of the specimens used for this study. LJAMM: Herpetological collection of the Centro Nacional Patagónico (CENPAT-CONICET), Puerto Madryn, Chubut, Argentina. ZVC-R: Vertebrate Zoology collection of the Faculty of Sciences, Montevideo, Uruguay. UFRGST: collection of the Herpetology Laboratory of the Federal University of Rio Grande d...

Table S2. Posterior probabilities of the number of species and each candidate species estimated by BPP 3.4 for all the replicates run. Each combination of starting tree and priors for Θ and τ (a-d) where run under four different seeds which are indicated with ’. Top1: ((((A, B), H), (C, D)), (E, (F, G))); Top2: ((((A, H), B), (C, D)), (E, (F, G)));...

Table S3. Lineage assignment for each of the 113 individual of Liolaemus wiegmannii with ddRADseq data, according to DAPC and RAxML. A: South-Central Argentina; B: Uruguay; D: Catamarca; E: Tucumán & Salta I; F: Jujuy and G: Salta II. All the individuals that belong to the lineage Mendoza C from BPP are recovered as part of lineage A (using ddRADse...

Figure S2. K values explored for the Liolaemus wiegmannii complex based on 3912 SNPs. Blue circle represents the best K under BIC (A) and AIC (B) criteria.

Figure S1. Bayesian cytochrome b genealogy of the Liolaemus wiegmannii complex considering haplotypes of L. gardeli and two unique haplotypes of Argentina: LJAMM 13266 (25 km N Villa Mercedes, General Pedernera Department, San Luis Province) and LJAMM 3132 (Copacabana, Sierras de Córdoba, Córdoba Province). Correspondence between colors and lineage...

Conferencia dictada en el Simposio: Diseccionando la Geografía de la Biodiversidad, en el Congreso Biociencias, 2019

The Uruguayan anphibian distribution is presented in a temporary window.

The continental and marine territories of Uruguay are characterised by a rich convergence of multiple biogeographic ecoregions of the Neotropics, making this country a peculiar biodiversity spot. However, despite the biological significance of Uruguay for the South American subcontinent, the distribution of biodiversity patterns in this country rem...

The demise of amphibians? Rapid spread of disease is a hazard in our interconnected world. The chytrid fungus Batrachochytrium dendrobatidis was identified in amphibian populations about 20 years ago and has caused death and species extinction at a global scale. Scheele et al. found that the fungus has caused declines in amphibian populations every...

Estimates of demographic parameters are scarce for Neotropical amphibians, a concerning fact because this region has the highest proportion of threatened amphibians in the world. We conducted a 3-year study where we applied a robust capture–mark–recapture design to assess the importance of breeding and non-breeding activity patterns over the surviv...

We analyzed the reproductive traits of a population of Melanophryniscus montevidensis. The reproductive events were associated to rainfalls. Males called from dawn to late night, were more abundant than females, and adopted alternative tactics to find partners (active search). Females were larger than males, and had mature oocytes and lipid reserve...

Conference presentation

Lizards of the Liolaemus wiegmannii group comprise 11 species that are widely distributed east of the Andes, occurring in Argentina, Uruguay, and Brazil. Here we analyzed a population of the genus Liolaemus, found in the Pampa region of Uruguay, on isolated sand dunes along the Tacuarembó River. We conducted biometric, meristic, and genetic compari...

Intraspecific morphological variation is a relatively common pattern among lizards, where several selective factors have been suggested as responsible for this phenomenon. For instance, geographic variation could result from natural selection along with historical processes, whereas sexual dimorphism has usually been attributed to sexual selection,...

This paper describes ecological features of the reproductive biology of a population of Elachistocleis bicolor from Uruguay. From a monthly sample obtained throughout a year, we measured mass of the fat bodies and the ovaries, testicular volume, and estimate fecundity. We found evidence of a relationship between reproductive activity and air temper...

Toads of the genus Melanophryniscus possess unique color patterns on the belly, which allows for individual recognition. Photo-identification has proven to be an efficient non-invasive technique to identify individuals for this genus. However, such color patterns are absent in newly metamorphosed individuals. We studied the development of the ventr...

Historically there has been taxonomic confusion among some Lygophis and Erythrolamprus species (previously belonging to the genus Liophis) due to their high similarity in color and general body form, in addition to a lack of understanding of their natural history and distribution. Lygophis anomalus is a common snake thought to be widely distributed...

Since 2000, the Sociedad Zoológica del Uruguay, along with the Uruguayan Committee of IUCN, leads a process to provide the herpetologists with the tools to conduct evaluations using the standardized criteria of IUCN. The new assessment process started in 2013 and followed entirely the IUCN guidelines, categories and criteria. All native amphibian s...

This paper describes the female reproductive pattern in a population of the frog Odontophrynus americanus from Uruguay. It is a species with explosive reproductive dynamics; such strategy has been little studied in temperate environments. Seventyfive adult females collected for one year were used, belonging to the Scientific Collection of the Facul...

The study of the patterns of movement is required to obtain knowledge of different aspects of the natural history of organisms, including foraging sites, shelter, breeding, capability of dispersion, and migration distance. This study analyzed the pattern of movements of a population of Melanophryniscus montevidensis among five sites selected in Bar...

The pattern of the testicular cycle and spermatogenic activity of the Neotropical yellow-striped snake Lygophis anomalus in Uru-guay was investigated. We gathered data on testicular size, seminiferous tubules, and histological samples of preserved specimens. Testis volume and seminiferous tubule diameter did not differ significantly over the year,...

Climate change (CC) constitutes one of the main biodiversity threats. The effects of CC on species are apparent worldwide, with primarily poleward and upward shifts in species distribution. Due to their narrow distribution, threatened species are highly vulnerable to CC. In this context, protected areas (PA) could be key tools for adaptation to CC....

This study describes the reproductive microhabitat of Melanophryniscus montevidensis and its use in two water bodies (WBs) in Barra de la Laguna de Rocha, Uruguay. Monthly field trips were performed between March 2012 and February 2013. Variables related to the WBs and vegetation, as well as parameters linked to the usage the amphibians make of the...

Climate change (CC) constitutes one of the main biodiversity threats. The effects of CC on species are apparent worldwide, with primarily poleward and upward shifts in species distribution. Due to their narrow distribution, threatened species are highly vulnerable to CC. In this context, protected areas (PA) could be key tools for adaptation to CC....

Lizards exhibit a variety of anti-predator strategies, but the most commonly used is escape. In the case of the lizard genus Teius they use mimesis with vegetation as a first strategy and escape as the second tactic. These lizards are fast runners and can run even using only the hind legs. Here we present data on the escape behaviour on Teius ocula...

We report the first feral population of Lithobates catesbeianus from Maldonado, whose origin is associated with a farm that was in activity between years 1993 and 2001. A potential expansion of this species toward the low basin of Maldonado stream could compromise the conservation of threatened anurans that occurs there.

We analyzed the reproductive pattern in males of Physalaemus riograndensis (n = 276). To identify the potential breeder males (n = 100), the presence of secondary sexual characters were recorded. These males were found mainly from September to April, and two peaks of abundance were observed. Breeding activity was positively correlated with temperat...

La Lista Roja de los Anfibios y Reptiles del Uruguay es el resultado de la evaluación realizada sobre la base de los criterios de la Unión Internacional para la Conservación de la Naturaleza (UICN) de todas las especies de estos grupos zoológicos de presencia confirmada en el país. Debido a sus características, los anfibios y reptiles son grupos q...

Cerro Verde Protected Area, on the coast of Uruguay, serves mainly to protect the marine fauna, which has charismatic species including marine turtles and dolphins. However, the terrestrial portion of this area has the conditions for hosting a great diversity of amphibians. The aims of this study were to build the inventory of amphibians from Cerro...

Validity of photo-identification technique to analyze natural markings in Melanophryniscus montevidensis (Anura: Bufonidae). Individual identification is useful for answering a variety of biological questions about animal life histories. Most of the techniques used to mark amphibians are invasive and can cause negative effects, compromising individ...

We studied the diet of the subtropical Lygophis anomalus through the analysis of 444 museum specimens collected along all its geographical range. Analysis of the stomach contents of specimens from all its distribution range indicate that this species feeds primarily on anurans, consuming reptiles like occasional items. Most of stomachs presented on...

Space and time are two of the main dimensions of the ecological niche. Because of their high dependence upon aquatic environments during breeding activity, anuran assemblages are interesting models for studying inter-populational relationships. The overlap in habitat use could be particularly high, especially for seasonal species and among taxa tha...

We used species distribution modeling to investigate the potential effects of climate change on 24 species of Neotropical anurans of the genus Melanophryniscus. These toads are small, have limited mobility, and a high percentage are endangered or present restricted geographical distributions. We looked at the changes in the size of suitable climati...

Species distributions are linked with climate. Among the effects predicted by the Intergovernmental Panel on Climate Change are changes in precipitation patterns and increases in mean temperatures—factors potentially having a major impact on threatened, rare, and endemic species. Using models to forecast possible changes in the distributions of dif...

The redbelly toadMelanophryniscus pachyrhynus(Miranda-Ribeiro, 1920) is a poorly known toad belonging to the M. tumifronsgroup, which inhabits rocky open areas on top of hilly landscapes of the Uruguayan Savanna ecoregion in Uruguay and southern Brazil. In this study we describe the advertisement and release calls from a redbelly toad population fr...

We describe the reproductive pattern of Liophis anomalus based on examination of museum specimens from its entire distribution area. This species shows seasonal activity, although follicles in secondary vitellogenesis were found throughout the year. Our data suggest that multiple clutches occur within a single reproductive period. As in many other...

This study describes the diet of Melanophryniscus devincenzii based on the analysis of stomach contents of 46 specimens from the Parque Municipal de Sertão, south Brazil. We found 935 items belonging to 33 prey categories (excluding plant material). The most important prey categories were Acari, ants (subfamilies Myrmicinae and Ponerinae) and beetl...

We describe the reproductive biology of female Physalaemus riograndensis from Uruguay. Mature ovaries with post-vitellogenic oocytes were extracted from females to obtain an index of reproductive investment (RI). Monthly variation in snout-vent-length (SVL, n=328) suggests a seasonal variation in reproductive activity. Gravid females were found bet...

RESUMEN Los anfibios anuros son de particular interés para la conservación ya que han sido señalados como uno de los grupos zoológicos más afectados por la pérdida global de diversidad. El presente trabajo tuvo como objetivo determinar la composición de la anurofauna en una microcuenca del arroyo Cuñapirú próxima a la ciudad de Rivera, Uruguay. En...