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Maureen A Donnelly - One of the best experts on this subject based on the ideXlab platform.

  • The tadpole of the bamboo–breeding poison frog Ranitomeya biolat (Anura: Dendrobatidae)
    2011
    Co-Authors: Rudolf Von May, Maureen A Donnelly
    Abstract:

    Ranitomeya biolat occurs in the lowland rainforest of southern Peru and northwestern Bolivia and uses bamboo internodes as a retreat and reproduction site (Morales 1992; Maldonado & Reichle 2007). Unlike other members of the vanzolinii group, which exhibit biparental care of tadpoles (Summers & McKeon 2004), we have observed that R. biolat exhibits male–only parental care and that tadpoles are transported individually and deposited in water–filled bamboo internodes (Medina–Müller 2006; R. von May, unpublished data). After more than 12 months of sampling, we never observed individuals providing trophic eggs to tadpoles or observed oophagy as clutches were laid 3.5 ± 1.5 cm above the water (n = 55); hence, tadpole oophagy may not be an important food resource as previously suspected (Waldram 2008). Though basic information on its breeding biology has been published (Waldram 2008), its tadpole remains undescribed. With the purpose of filling this gap, we here describe the tadpole of R. biolat. Twenty tadpoles (MUSM–27564) were collected at the Los Amigos Research Center (SE Perú, 12°34'07 " S, 70°05'57 " W; 270 m elevation) in March 2003 and March 2007, and were fixed and stored in 10 % formalin. Descriptions follow the format of Caldwell et al. (2002) and measurements (to nearest 0.01 mm) were made using a Nikon SMZ 800 dissenting microscope with a micrometer scale attached to an ocular lens. Terminology follows Altig & McDiarmid (1999). Drawings of a single specimen were made by MMM using a camera lucida attached to the microscope. The morphology of all the other individuals observed was similar in appearance (n = 19). Morphometric measurements wer

  • experimental evidence for aposematism in the dendrobatid poison frog oophaga pumilio
    Copeia, 2007
    Co-Authors: Ralph A. Saporito, Rachel Zuercher, Marcus Roberts, Kenneth G Gerow, Maureen A Donnelly
    Abstract:

    Brightly colored poison frogs of the family Dendrobatidae contain an alkaloid-based chemical defense against predation. The bright coloration of these frogs is generally considered an aposematic signal to potential predators; however, relatively few studies have specifically tested this hypothesis. Herein we report the results of a field-based experiment designed to test the hypothesis of aposematism in the dendrobatid frog, Oophaga (=Dendrobates) pumilio from the La Selva Biological Station, Costa Rica. We used plasticine frog models to evaluate natural predation rates as a function of color. Predation rates on brown models were almost twice that of red models, suggesting that predators avoid brightly colored frog models. Birds accounted for the majority of attacks on the models. The results of this study provide experimental evidence in support of the hypothesis that bright coloration in dendrobatids functions as an aposematic signal to predators.

  • a siphonotid millipede rhinotus as the source of spiropyrrolizidine oximes of dendrobatid frogs
    Journal of Chemical Ecology, 2003
    Co-Authors: Ralph A. Saporito, Maureen A Donnelly, R L Hoffman, H M Garraffo, John W Daly
    Abstract:

    Poison frogs of the neotropical family Dendrobatidae contain a wide variety of lipophilic alkaloids, which are accumulated from alkaloid-containing arthropods. A small millipede, Rhinotus purpureus (Siphonotidae), occurs microsympatrically with the dendrobatid frog Dendrobates pumilio on Isla Bastimentos, Bocas del Toro Province, Panama. Methanol extracts of this millipede contain the spiropyrrolizidine O-methyloxime 236, an alkaloid previously known only from skin extracts of poison frogs, including populations of D. pumilio. Thus, R. purpureus represents a likely dietary source of such alkaloids in dendrobatid frogs.

  • bioactive alkaloids of frog skin combinatorial bioprospecting reveals that pumiliotoxins have an arthropod source
    Proceedings of the National Academy of Sciences of the United States of America, 2002
    Co-Authors: John W Daly, Thomas F Spande, Martin H Garraffo, Tetsuo Kaneko, Jason M Wilham, Alex Espinosa, Maureen A Donnelly
    Abstract:

    Nearly 500 alkaloids have been detected in skin extracts from frogs of the family Dendrobatidae. All seem to have been sequestered unchanged into skin glands from alkaloid-containing arthropods. Ants, beetles, and millipedes seem to be the source of decahydroquinolines, certain izidines, coccinellines, and spiropyrrolizidine oximes. But the dietary source for a major group of frog-skin alkaloids, namely the pumiliotoxins (PTXs), alloPTXs, and homoPTXs, remained a mystery. In hopes of revealing an arthropod source for the PTX group, small arthropods were collected from eight different sites on a Panamanian island, where the dendrobatid frog (Dendrobates pumilio) was known to contain high levels of two PTXs. The mixed arthropod collections from several sites, each representing up to 20 arthropod taxa, contained PTX 307A and/or alloPTX 323B. In addition, the mixed arthropod collections from several sites contained a 5,8-disubstituted indolizidine (205A or 235B), representing another class of alkaloids previously unknown from an arthropod. An ant alkaloid, decahydroquinoline 195A, was detected in the mixed arthropod collections from several sites. Thus, “combinatorial bioprospecting” demonstrates that further collection and analysis of individual taxa of leaf-litter arthropods should reveal the taxa from which PTXs, alloPTXs, and 5,8-disubstituted indolizidines are derived.

  • herpetofauna of the yutaje corocoro massif venezuela second report from the robert g goelet american museum terramar expedition to the northwestern tepuis
    Bulletin of the American Museum of Natural History, 2001
    Co-Authors: Charles W. Myers, Maureen A Donnelly
    Abstract:

    Abstract The Yutaje–Corocoro massif is a highly eroded sandstone table mountain, with internal drainage mainly to the central valley of the Rio Corocoro, a stream in the headwater drainage of the Rio Manapiare—some 100 km east of the middle Rio Orinoco, at the northern edge of the State of Amazonas in southern Venezuela. The rocky soil supports a mosaic of diverse scrubland and forest, with small tepui meadows at the higher elevations. The herpetofauna is depauperate, as is typical of the Venezuelan tepuis. Eight species of amphibians and reptiles were collected during a 7-day period in the dry season (February). This sample includes two new frogs (Hyalinobatrachium eccentricum, n. sp., Centrolenidae; Colostethus undulatus, n. sp., Dendrobatidae) and a new genus and species of lizards (Adercosaurus vixadnexus, n. gen. & sp., Teiidae), all of which were found in humid montane mossy forest at 1700–1750 m elevation. Another new lizard (Tropidurus panstictus, n. sp., Tropiduridae) was discovered at lower elev...

David C Cannatella - One of the best experts on this subject based on the ideXlab platform.

  • Convergent Substitutions in a Sodium Channel Suggest Multiple Origins of Toxin Resistance in Poison Frogs
    Molecular biology and evolution, 2016
    Co-Authors: Rebecca D. Tarvin, Juan C. Santos, Lauren A. O’connell, Harold H. Zakon, David C Cannatella
    Abstract:

    Complex phenotypes typically have a correspondingly multifaceted genetic component. However, the genotype–phenotype association between chemical defense and resistance is often simple: genetic changes in the binding site of a toxin alter how it affects its target. Some toxic organisms, such as poison frogs (Anura: Dendrobatidae), have defensive alkaloids that disrupt the function of ion channels, proteins that are crucial for nerve and muscle activity. Using protein-docking models, we predict that three major classes of poison frog alkaloids (histrionicotoxins, pumiliotoxins, and batrachotoxins) bind to similar sites in the highly conserved inner pore of the muscle voltage-gated sodium channel, Nav1.4. We predict that poison frogs are somewhat resistant to these compounds because they have six types of amino acid replacements in the Nav1.4 inner pore that are absent in all other frogs except for a distantly related alkaloid-defended frog from Madagascar, Mantella aurantiaca. Protein-docking models and comparative phylogenetics support the role of these replacements in alkaloid resistance. Taking into account the four independent origins of chemical defense in Dendrobatidae, phylogenetic patterns of the amino acid replacements suggest that 1) alkaloid resistance in Nav1.4 evolved independently at least seven times in these frogs, 2) variation in resistance-conferring replacements is likely a result of differences in alkaloid exposure across species, and 3) functional constraint shapes the evolution of the Nav1.4 inner pore. Our study is the fi rst to demon strate the genetic basis of autoresistance in frogs with alkaloid defenses.

  • evolution of dietary specialization and chemical defense in poison frogs Dendrobatidae a comparative analysis
    The American Naturalist, 2005
    Co-Authors: Catherine R Darst, Pablo A Menendezguerrero, Luis A Coloma, David C Cannatella
    Abstract:

    Abstract: Defensive mechanisms, including noxious or toxic substances, are favored by predation‐driven natural selection. The acquisition of noxious/toxic substances can be either endogenous, in which the substances are produced by the organism, or exogenous, in which the substances are produced by another organism and are sequestered. Evidence indicates that the defensive skin alkaloids of Neotropical poison frogs (Dendrobatidae) have an exogenous source: a diet of ants and other small alkaloid‐containing arthropods, which we term the diet‐toxicity hypothesis. A critical prediction of the diet‐toxicity hypothesis is that independent origins of dietary specialization will be found to be correlated with independent origins of skin alkaloids. We tested this prediction in an integrated framework using comparative methods with new and published data on feeding ecology and chemical defense for 15 species of dendrobatids in five genera. We found a significant correlation between alkaloid profiles and degree of ...

  • novel relationships among hyloid frogs inferred from 12s and 16s mitochondrial dna sequences
    Molecular Phylogenetics and Evolution, 2004
    Co-Authors: Catherine R Darst, David C Cannatella
    Abstract:

    Advanced frogs (Neobatrachia) are usually divided into two taxa, Ranoidea (the firmisternal frogs) and Hyloidea (all other neobatrachians). We investigated phylogenetic relationships among several groups of Hyloidea using 12S and 16S rRNA mitochondrial gene sequences and tested explicit relationships of certain problematic hyloid taxa using a sample of 93 neobatrachians. Parsimony, maximum likelihood, and Bayesian inference methods suggest that both the Ranoidea and Hyloidea are well-supported monophyletic groups. We reject three hypotheses using parametric bootstrap simulation: (1) Dendrobatidae lies within the Ranoidea; (2) The group containing Hylidae, Pseudidae, and Centrolenidae is monophyletic; and (3) Brachycephalus is part of Bufonidae.

Heike Prohl - One of the best experts on this subject based on the ideXlab platform.

Janalee P. Caldwell - One of the best experts on this subject based on the ideXlab platform.

  • A taxonomic revision of the Neotropical poison frog genus Ranitomeya (Amphibia: Dendrobatidae)
    Zootaxa, 2011
    Co-Authors: Jason L. Brown, Adolfo Amezquita, Evan Twomey, Moisés Barbosa De Souza, Janalee P. Caldwell, Stefan Lötters, Rudolf Von May, Paulo Roberto Melo-sampaio, Daniel Mejía-vargas, Pedro E. Perez-peña
    Abstract:

    The Neotropical poison frog genus Ranitomeya is revised, resulting in one new genus, one new species, five synonymies and one species classified as nomen dubium. We present an expanded molecular phylogeny that contains 235 terminals, 104 of which are new to this study. Notable additions to this phylogeny include seven of the 12 species in the minuta group, 15 Ranitomeya amazonica, 20 R. lamasi, two R. sirensis, 30 R. ventrimaculata and seven R. uakarii. Previous researchers have long recognized two distinct, reciprocally monophyletic species groups contained within Ranitomeya, sensu Grant et al. 2006: the ventrimaculata group, which is distributed throughout much of the Amazon, and the minuta group of the northern Andes and Central America. We restrict Ranitomeya to the former group and erect a new genus, Andinobates Twomey, Brown, Amezquita & Mejia-Vargas gen. nov., for members of the minuta group. Other major taxonomic results of the current revision include the following: (i) A new species, Ranitomeya toraro Brown, Caldwell, Twomey, Melo-Sampaio & Souza sp. nov., is described from western Brazil. This species has long been referred to as R. ventrimaculata but new morphological and phylogenetic data place it sister to R. defleri. (ii) Examination of the holotype of R. ventrimaculata revealed that this specimen is in fact a member of what is currently referred to as R. duellmani, therefore, Dendrobates duellmani Schulte 1999 is considered herein a junior synonym of D. ventrimaculatus Shreve 1935 (= R. ventrimaculata). (iii) For the frogs that were being called R. ventrimaculata prior to this revision, the oldest available and therefore applicable name is R. variabilis. Whereas previous definitions of R. variabilis were restricted to spotted highland frogs near Tarapoto, Peru, our data suggest that this color morph is conspecific with lowland striped counterparts. Therefore, the definition of R. variabilis is greatly expanded to include most frogs which were (prior to this revision) referred to as R. ventrimaculata. (iv) Phylogenetic and bioacoustic evidence support the retention of R. amazonica as a valid species related to R. variabilis as defined in this paper. Based on phylogenetic data, R. amazonica appears to be distributed throughout much of the lower Amazon, as far east as French Guiana and the Amazon Delta and as far west as Iquitos, Peru. (v) Behavioral and morphological data, as well as phylogenetic data which includes topotypic material of R. sirensis and numerous samples of R. lamasi, suggest that the names sirensis, lamasi and biolat are applicable to a single, widespread species that displays considerable morphological variation throughout its range. The oldest available name for this group is sirensis Aichinger; therefore, we expand the definition of R. sirensis. (vi) Ranitomeya ignea and R. intermedia, elevated to the species status in a previous revision, are placed as junior synonyms of R. reticulata and R. imitator, respectively. (vii) Ranitomeya rubrocephala is designated as nomen dubium. In addition to taxonomic changes, this revision includes the following: (i) Explicit definitions of species groups that are consistent with our proposed taxonomy. (ii) A comprehensive dichotomous key for identification of ‘small’ aposematic poison frogs of South and Central America. (iii) Detailed distribution maps of all Ranitomeya species, including unpublished localities for most species. In some cases, these records result in substantial range extensions (e.g., R. uakarii, R. fantastica). (iv) Tadpole descriptions for R. amazonica, R. flavovittata, R. imitator, R. toraro sp. nov., R. uakarii and R. variabilis; plus a summary of tadpole morphological data for Andinobates and Ranitomeya species. (v) A summary of call data on most members of Andinobates and Ranitomeya, including call data of several species that have not been published before. (vi) A discussion on the continued impacts of the pet trade on poison frogs (vii) A discussion on several cases of potential Mullerian mimicry within the genus Ranitomeya. We also give opinions regarding the current debate on recent taxonomic changes and the use of the name Ranitomeya.

  • phylogenetic systematics of dart poison frogs and their relatives amphibia athesphatanura Dendrobatidae
    Bulletin of the American Museum of Natural History, 2006
    Co-Authors: Janalee P. Caldwell, Taran Grant, Darrel R Frost, Ron Gagliardo, Celio F B Haddad, Philippe J R Kok, Bruce D Means, Brice P Noonan, Walter E Schargel
    Abstract:

    Abstract The known diversity of dart-poison frog species has grown from 70 in the 1960s to 247 at present, with no sign that the discovery of new species will wane in the foreseeable future. Although this growth in knowledge of the diversity of this group has been accompanied by detailed investigations of many aspects of the biology of dendrobatids, their phylogenetic relationships remain poorly understood. This study was designed to test hypotheses of dendrobatid diversification by combining new and prior genotypic and phenotypic evidence in a total evidence analysis. DNA sequences were sampled for five mitochondrial and six nuclear loci (approximately 6,100 base pairs [bp]; x¯ = 3,740 bp per terminal; total dataset composed of approximately 1.55 million bp), and 174 phenotypic characters were scored from adult and larval morphology, alkaloid profiles, and behavior. These data were combined with relevant published DNA sequences. Ingroup sampling targeted several previously unsampled species, including Ar...

  • a new amazonian species of colostethus anura Dendrobatidae with a nidicolous tadpole
    Herpetologica, 2003
    Co-Authors: Janalee P. Caldwell, Albertina P Lima
    Abstract:

    We describe adults, tadpoles, and vocalization of a new Amazonian species of Colostethus from a terra firme rainforest locality south of the Amazon River near Manaus, Amazonas, Brazil. This species is characterized by the absence of dorsolateral and ventrolateral stripes, the presence of a short, diffuse oblique lateral stripe, Finger III of male not swollen, and the presence of a black or gray throat in the male. In addition, the new species is larger than three other species in the Amazon region (C. caeruleodactylus, C. marchesianus, and C. stepheni) and its call, typically composed of long bouts of continuous notes, is distinct from these three species. This species is the fourth known Colostethus with an endotrophic tadpole; in three of these species, including C. nidicola, eggs are deposited and develop entirely in a terrestrial nest. Clutches of C. nidicola are composed of about three eggs and are placed in leaf litter on the forest floor. Whether C. nidicola is closely related to any of the other t...

  • The evolution of myrmecophagy and its correlates in poison frogs (Family Dendrobatidae)
    Journal of Zoology, 1996
    Co-Authors: Janalee P. Caldwell
    Abstract:

    Poison frogs (Family Dendrobatidae) are common leaf litter inhabitants of New World tropical rainforests. The name of this group derives from several genera (especially Dendrobates, Minyobates, and Phyllobates) that are aposematically coloured and have toxic skin to varying degrees. Other species in the family, primarily the genus Colostethus, are cryptically coloured and non-toxic. Recent studies have revealed that the toxic compounds in the skin, which are lipophilic alkaloids, may have a dietary origin. Diets and associated characteristics, prey size, prey number, and niche breadth, of nine species in five genera, three of which have poisonous species, were examined. Interpretation of these characteristics in light of an independently constructed cladogram revealed the inclusion of a high percentage of Formicidae (ants) in the diets of toxic species. Although alkaloids have been reported in several insect groups, more alkaloids are known from ants than any other group. Species in the genus Dendrobates, which are poisonous and have many other derived characters, have diets composed of 50–73% ants, whereas percentages of ants used by non-toxic species in the genus Colostethus was 12–16%. Ants are the major prey category consumed by the five poisonous species considered in this study. In general, frogs separated into two groups. More basal groups with non-toxic skin and cryptic coloration had diets with low percentages of ants, low numbers of prey per individual, and high niche breadths, indicating inclusion of a broad range of prey categories in their diets. Species with poisonous skin and aposematic coloration had diets with large percentages of ants, large numbers of prey per individual, and low niche breadths, indicating diets with relatively few prey categories. Thus, diet, and the subsequent evolution of uptake systems for alkaloids, may be the primary character that led to the development of toxic skin and permitted aposematism, leading to radiation of poisonous species.

Adolfo Amezquita - One of the best experts on this subject based on the ideXlab platform.

  • the advertisement call of ameerega pulchripecta silverstone 1976 anura Dendrobatidae
    Zootaxa, 2016
    Co-Authors: Carlos Eduardo Costacampos, Albertina P Lima, Adolfo Amezquita
    Abstract:

    The name Ameerega picta was once used to denote a lineage of poison frogs (Dendrobatidae) distributed throughout most of the Amazon basin (Silverstone 1976); more recently, to describe a phenetic group involving at least 18 species, Lotters et al . (2007) pointed out that some of the lineages were indeed derived from the former A. picta . Among them, the nominal species with the widest distribution is A. hahneli (Haddad & Martins 1994; Twomey & Brown 2008), also an alleged complex of poorly defined species (Grant et al . 2006; Fouquet et al . 2007; Roberts et al . 2007). The mate-recognition signal, the advertisement call, was part of the evidence used to revalidate A. hahneli as a different species from A. picta. Although the advertisement call has been described for one or few individuals of other species in the group (Haddad & Martins 1994; Costa et al . 2006; Twomey & Brown 2008; Lotters et al. 2009), namely A. flavopicta, A. braccata and A. boehmei , and A. hahneli , we still lack a formal description for A. pulchripecta , the sister taxon of A. hahneli (Twomey & Brown 2008) . Its call has been qualitatively described as similar to A. hahneli ’s call, but “deeper-voiced” (Lotters et al. 2007).

  • hybridization promotes color polymorphism in the aposematic harlequin poison frog oophaga histrionica
    Ecology and Evolution, 2013
    Co-Authors: Iliana Medina, Ian J. Wang, Camilo Salazar, Adolfo Amezquita
    Abstract:

    Whether hybridization can be a mechanism that drives phenotypic diversity is a widely debated topic in evolutionary biology. In poison frogs (Dendrobatidae), assortative mating has been invoked to explain how new color morphs persist despite the expected homogenizing effects of natural selection. Here, we tested the complementary hypothesis that new morphs arise through hybridization between different color morphs. Specifically, we (1) reconstructed the phylogenetic relationships among the studied populations of a dart-poison frog to provide an evolutionary framework, (2) tested whether microsatellite allele frequencies of one putative hybrid population of the polymorphic frog O. histrionica are intermediate between O. histrionica and O. lehmanni, and (3) conducted mate-choice experiments to test whether putatively intermediate females prefer homotypic males over males from the other two populations. Our findings are compatible with a hybrid origin for the new morph and emphasize the possibility of hybridization as a mechanism generating variation in polymorphic species. Moreover, because coloration in poison frogs is aposematic and should be heavily constrained, our findings suggest that hybridization can produce phenotypic novelty even in systems where phenotypes are subject to strong stabilizing selection.

  • A taxonomic revision of the Neotropical poison frog genus Ranitomeya (Amphibia: Dendrobatidae)
    Zootaxa, 2011
    Co-Authors: Jason L. Brown, Adolfo Amezquita, Evan Twomey, Moisés Barbosa De Souza, Janalee P. Caldwell, Stefan Lötters, Rudolf Von May, Paulo Roberto Melo-sampaio, Daniel Mejía-vargas, Pedro E. Perez-peña
    Abstract:

    The Neotropical poison frog genus Ranitomeya is revised, resulting in one new genus, one new species, five synonymies and one species classified as nomen dubium. We present an expanded molecular phylogeny that contains 235 terminals, 104 of which are new to this study. Notable additions to this phylogeny include seven of the 12 species in the minuta group, 15 Ranitomeya amazonica, 20 R. lamasi, two R. sirensis, 30 R. ventrimaculata and seven R. uakarii. Previous researchers have long recognized two distinct, reciprocally monophyletic species groups contained within Ranitomeya, sensu Grant et al. 2006: the ventrimaculata group, which is distributed throughout much of the Amazon, and the minuta group of the northern Andes and Central America. We restrict Ranitomeya to the former group and erect a new genus, Andinobates Twomey, Brown, Amezquita & Mejia-Vargas gen. nov., for members of the minuta group. Other major taxonomic results of the current revision include the following: (i) A new species, Ranitomeya toraro Brown, Caldwell, Twomey, Melo-Sampaio & Souza sp. nov., is described from western Brazil. This species has long been referred to as R. ventrimaculata but new morphological and phylogenetic data place it sister to R. defleri. (ii) Examination of the holotype of R. ventrimaculata revealed that this specimen is in fact a member of what is currently referred to as R. duellmani, therefore, Dendrobates duellmani Schulte 1999 is considered herein a junior synonym of D. ventrimaculatus Shreve 1935 (= R. ventrimaculata). (iii) For the frogs that were being called R. ventrimaculata prior to this revision, the oldest available and therefore applicable name is R. variabilis. Whereas previous definitions of R. variabilis were restricted to spotted highland frogs near Tarapoto, Peru, our data suggest that this color morph is conspecific with lowland striped counterparts. Therefore, the definition of R. variabilis is greatly expanded to include most frogs which were (prior to this revision) referred to as R. ventrimaculata. (iv) Phylogenetic and bioacoustic evidence support the retention of R. amazonica as a valid species related to R. variabilis as defined in this paper. Based on phylogenetic data, R. amazonica appears to be distributed throughout much of the lower Amazon, as far east as French Guiana and the Amazon Delta and as far west as Iquitos, Peru. (v) Behavioral and morphological data, as well as phylogenetic data which includes topotypic material of R. sirensis and numerous samples of R. lamasi, suggest that the names sirensis, lamasi and biolat are applicable to a single, widespread species that displays considerable morphological variation throughout its range. The oldest available name for this group is sirensis Aichinger; therefore, we expand the definition of R. sirensis. (vi) Ranitomeya ignea and R. intermedia, elevated to the species status in a previous revision, are placed as junior synonyms of R. reticulata and R. imitator, respectively. (vii) Ranitomeya rubrocephala is designated as nomen dubium. In addition to taxonomic changes, this revision includes the following: (i) Explicit definitions of species groups that are consistent with our proposed taxonomy. (ii) A comprehensive dichotomous key for identification of ‘small’ aposematic poison frogs of South and Central America. (iii) Detailed distribution maps of all Ranitomeya species, including unpublished localities for most species. In some cases, these records result in substantial range extensions (e.g., R. uakarii, R. fantastica). (iv) Tadpole descriptions for R. amazonica, R. flavovittata, R. imitator, R. toraro sp. nov., R. uakarii and R. variabilis; plus a summary of tadpole morphological data for Andinobates and Ranitomeya species. (v) A summary of call data on most members of Andinobates and Ranitomeya, including call data of several species that have not been published before. (vi) A discussion on the continued impacts of the pet trade on poison frogs (vii) A discussion on several cases of potential Mullerian mimicry within the genus Ranitomeya. We also give opinions regarding the current debate on recent taxonomic changes and the use of the name Ranitomeya.

  • differential evolution of advertisement call traits in dart poison frogs anura Dendrobatidae
    Ethology, 2009
    Co-Authors: Luciana K Erdtmann, Adolfo Amezquita
    Abstract:

    The ability to recognise and discriminate between heterospecific and conspecific individuals plays an essential role in mate choice, reproductive isolation and thus species diversification. Many animals discriminate based on advertisement calls, whose evolution may be driven by a variety of forces such as natural selection, sexual selection or stochastic processes. The relative importance of stochastic processes acting on a given trait is usually correlated with its phylogenetic signal. Mate-recognition signals are complex traits composed of multiple features that could potentially respond independently to evolutionary forces. The advertisement call of anurans is used in species recognition and mate choice. In this study, we estimate the phylogenetic signal for body size and a suite of traits describing the male advertisement call from dart-poison frogs (Anura: Dendrobatidae). We found a surprisingly high phylogenetic signal for all call traits. In addition, call traits varied in their degree of phylogenetic signal, suggesting that evolutionary forces have been acting differently on different traits. Pulse duration showed the strongest phylogenetic signal. Peak frequency and body size were correlated and presented high phylogenetic signal indicating that the evolution of one trait may be driving or constraining the other. Since most variation in call traits can be explained by the phylogenetic history of the species, we cannot reject the hypothesis that stochastic processes account for significant evolutionary divergence in frog calls.

  • auditory matching of male epipedobates femoralis anura Dendrobatidae under field conditions
    Animal Behaviour, 2005
    Co-Authors: Adolfo Amezquita, Lina Castellanos, Walter Hodl
    Abstract:

    In the evolution of species recognition mechanisms, the differential reactions of receivers towards a signal may be as important as variation in the signal features. In many animals, the auditory system's most sensitive range often matches the dominant frequency range of the signals. The degree of spectral matching, however, can be modified by stimulus intensity and, therefore, patterns detected in the laboratory should ideally be confirmed by field experiments. Territorial males of the dart-poison frog, Epipedobates femoralis, approach vocally active conspecific intruders. Since phonotaxis (followed by fighting) affects male fitness, the auditory system is predicted to discriminate against heterospecific calls. We tested the role of spectral and temporal call features in call discrimination by conducting playback experiments in the field with synthetic calls. To study the effect of heterospecific interference on the male's phonotactic reaction, we measured signal parameters and signalling activity of four sympatric species. The highest probability of response coincided with the spectral and temporal features of the population's advertisement call and the probability of approach was matched to the average frequency of this call. In addition, the degree of matching was sensitive to the number of notes per call. The decrease in the probability of response, however, was steeper at lower than average frequencies, where the probability of heterospecific interference was highest. Our results suggest that under field conditions frequency tuning interacts with temporal call features in maximizing the detection of conspecific signals and reducing the probability of heterospecific interference.