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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 understood. In order to test its monophyly and the relationships among its species, we performed a total evidence phylogenetic analysis of sequences of three mitochondrial and three nuclear genes, and 193 phenotypic characters from all species of Sphaenorhynchus. Our results support the monophyly of Sphaenorhynchus with molecular and phenotypic evidence, with S. pauloalvini as the earliest diverging taxon, followed by S. carneus, as the sister taxon of all remaining species of the genus. We recognize three species groups in Sphaenorhynchus (the S. lacteus, S. planicola and S. platycephalus groups), to facilitate its taxonomic study; only three species (S. carneus, S. pauloalvini and S. prasinus) remain unassigned to any group. Sequence data were not available for only two species (S. bromelicola and S. palustris) for which we scored phenotypic data; wildcard behaviour was detected only in S. bromelicola nested inside the S. platycephalus group. On the basis of the resulting phylogenetic hypothesis, we discuss the evolution of oviposition site and a number of phenotypic characters that could be associated with heterochronic events in the evolutionary history of this group. Fil: de Araujo Vieira, Katyuscia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Blotto Acuña, Boris Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Universidade de Sao Paulo; Brasil Fil: Confalonieri, Ulisses. Universidade Federal do Rio de Janeiro; Brasil Fil: Baptista Haddad, Célio Fernando. Universidade Estadual Paulista Julio de Mesquita Filho; Brasil Fil: Faivovich, Julián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina Fil: Grant, Taran. Universidade de Sao Paulo; Brasil

We describe the buccopharyngeal morphology of the dendrobatid poison frog Ameerega flavopicta—the first such description for the genus—and discuss diagnostic characters and variation of bu...

The trans-Andean genus Epipedobates comprises seven species, of which tadpoles have been described for five. Herein, we describe the tadpole of Epipedobates darwinwallacei and compare it to free-swimming tadpoles of E. anthonyi, E. boulengeri, E. espinosai, E. machalilla, E. narinensis, and E. tricolor. Furthermore, we suggest as putative synapomorphies for the genus Epipedobates the following larval character-states: (i) shelf on the upper jaw sheath, and (ii) subcutaneous melanophores distributed in two transverse bands in the peribranchial area. Additionally, the presence of white spots on the anterolateral and ventrolateral surfaces of the body is possibly synapomorphic but requires further study.

Amezquita et al. (2017) recently concluded that species of the Allobates femoralis group are toxic to mice at levels equivalent to syntopic alkaloid-containing poison frogs, which they attributed to the presence of alkaloids in skin secretions. However, the chemical composition of skin secretions was not analyzed, and here we present additional data supporting the absence of alkaloids in skin secretions of the Allobates femoralis group. Instead, we suggest the observed toxicity was caused by the anesthetic benzocaine, which was applied to the buccal cavity to euthanize frogs prior to skin removal. We show that orally administered benzocaine is rapidly incorporated into the skin of species that sequester and do not sequester alkaloids, which casts doubt on the conclusion that Allobates femoralis group skin secretions are toxic and makes the results of experiments with alkaloid-containing species of Adelphobates and Ameerega uninterpretable. To prevent experimental errors and misinterpretations in studies of amphibian chemical defense, we encourage researchers to test the chemical composition of samples prior to experimentation, include all necessary controls to detect false positives, conduct small pilot studies for new methods, and consider the limitations of particular methods and their ability to address the intended research questions.

We describe a striking new species of the genus Sachatamia from the eastern slope of Colombia's Central Andes. The new species differs from the most closely related species (i.e., Sachatamia albomaculata and S. punctulata) by its green dorsal coloration in life with yellow and blue dots, and unique semicirclular, white blotch in the dorsal portion of the iris. With this new species, we increase the currently recognized species in the genus to five. Mitochondrial DNA sequences corroborate both the phylogenetic position of the new species within Sachatamia and its status as a new species. In addition, in light of our results some taxonomic implications are briefly discussed.

Centrolenidae is a monophyletic group of Neotropical tree frogs. Centrolenid tadpoles usually lack pigmentation on their bodies, presenting reddish coloration in life, and are fossorial. Several phenotypic characters have been associated with fossoriality, but data on larval morphology is scarce. Herein, we describe the buccopharyngeal morphology of two Vitreorana tadpoles and identify putative synapomorphies for the family, including 1) the presence of vacuities on the buccal roof arena; 2) the nares being oriented longitudinally; 3) the presence of a conical median ridge at the end of the postnarial arena; and 4) the posterior–most pair of postnarial papilla being aligned in row with the median ridge.

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 an arboreal species (the hylid Triprion petasatus), define the layers in which these muscles are arranged, and attribute presumed functions. On the basis of our myological analysis of 155 species representing 46 of the 54 currently recognized families and main clades of anurans, we describe 20 characters related to hand and foot muscles. Optimization of these characters on the most recent and inclusive phylogenetic hypothesis of Anura results in synapomorphies for several major clades (Bombinatoridae, Alytidae, Xenoanura + Acosmanura, Xenoanura, Pipidae, Acosmanura, Anomocoela, Scaphiopodidae, Pelodytidae + Pelobatidae + Megophryidae, Megophryidae, Neobatrachia, Heleophrynidae, Sooglossidae, Laurentobatrachia, Calyptocephalellidae, Myobatrachoidea, and Nobleobatrachia), including new, nonhomoplastic synapomorphies for clades previously supported only by molecular evidence and a few conflicting phenotypic characters (e.g., Acosmanura, Anomocoela, Neobatrachia). Additionally, we (1) address controversies regarding the homology of anuran and caudate muscles in the context of putative synapomorphies for Ascaphidae + Leiopelmatidae and its sister clade Lalagobatrachia; (2) evaluate a recently proposed terminology for anuran hand and foot musculature; (3) discuss the identities of several hand and foot muscles with problematic homologies; (4) establish a unified terminology for anuran hand and foot muscles, including a list of synonyms for all names employed in the literature; and (5) propose hypotheses for the origin of several myological novelties (neomorphs).

Made available in DSpace on 2020-12-10T19:54:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-03-27 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Rede Baiana de Pesquisa sobre Anfibios (RBPA) Fundacao O Boticario de Protecao a Natureza Fundacao de Amparo a Pesquisa da Bahia (FAPESB) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Mohamed bin Zayed Species Conservation Fund Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) Smithsonian Institution (USA) Agencia Nacional de Promocion Cientifica y Tecnologica (ANPCyT) 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 rainforests to semiarid scrubland. In this paper, we present a phylogenetic analysis of this hylid tribe based on sequence fragments of up to five mitochondrial (12S, 16S, ND1, COI, Cytb) and six nuclear genes (POMC, RAG-1, RHOD, SIAH, TNS3, TYR). We included most of its species (> 96%), in addition to a number of new species. Our results indicate: (i) the paraphyly of Trachycephalus with respect to Aparasphenodon venezolanus; (ii) the nonmonophyly of Aparasphenodon, with Argenteohyla siemersi, Corythomantis galeata and Nyctimantis rugiceps nested within it, and Ap. venezolanus nested within Trachycephalus; (iii) the polyphyly of Corythomantis; (iv) the nonmonophyly of the recognized species groups of Phyllodytes; and (v) a pervasive low support for the deep relationships among the major clades of Lophyohylini, including C. greeningi and the monotypic genera Itapotihyla and Phytotriades. To remedy the nonmonophyly of Aparasphenodon, Corythomantis, and Trachycephalus, we redefined Nyctimantis to include Aparasphenodon (with the exception of Ap. venezolanus, which we transferred to Trachycephalus), Argenteohyla, and C. galeata. Additionally, our results indicate the need for taxonomic work in the following clades: (i) Trachycephalus dibernardoi and Tr. imitatrix; (ii) Tr. atlas, Tr. mambaiensis and Tr. nigromaculatus; and (iii) Phyllodytes. On the basis of our phylogenetic results, we analyzed the evolution of skull hyperossification and reproductive biology, with emphasis on the multiple independent origins of phytotelm breeding, in the context of Anura. We also analyzed the inter-related aspects of chemical defences, venom delivery, phragmotic behaviour, co-ossification, and prevention of evaporative water loss. Univ Estadual Paulista, Inst Biociencias, Dept Biodiversidade, Av 24A 1515, BR-13506900 Rio Claro, SP, Brazil Univ Estadual Paulista, Inst Biociencias, Ctr Aquicultura, Av 24A 1515, BR-13506900 Rio Claro, SP, Brazil Univ Sao Paulo, Inst Biociencias, Dept Zool, BR-05508090 Sao Paulo, SP, Brazil Univ Fed Rio de Janeiro, Museu Nacl, Dept Vertebrados, Setor Herpetol, BR-20940040 Rio De Janeiro, RJ, Brazil Univ Estadual Santa Cruz, Dept Ciencias Biol, Trop Herpetol Lab, Rodovia Jorge Amado,Km 16, BR-45662900 Ilheus, BA, Brazil Univ Brasilia, Dept Engn Florestal, Lab Fauna & Unidades Conservacao, BR-70910900 Brasilia, DF, Brazil Univ Fed Vicosa, Dept Biol Anim, Museu Zool Joao Moojen, BR-36570900 Vicosa, MG, Brazil Univ West Indies, Zool Museum, Dept Life Sci, St Augustine, Trinidad Tobago Pontificia Univ Catolica Rio Grande do Sul, Lab Sistemat Vertebrados, Av Ipiranga 6681,Predio 40,Sala 110, BR-90619900 Porto Alegre, RS, Brazil Consejo Nacl Invest Cient & Tecn, UNaM, Inst Biol Subtrop, Lab Genet Evolut Claudio Juan Bidau, Felix Azara 1552,CPA N3300LQF Posadas, Misiones, Argentina Univ Estadual Paulista, Inst Biociencias, Lab Herpetol, Campus Litoral Paulista, BR-11330900 Sao Vicente, SP, Brazil Univ Nacl Nordeste, CONICET, Fac Ciencias Exactas & Nat & Agrimensura, Lab Herpetol,Dept Biol, Av Libertad 5470, RA-3400 Corrientes, Argentina Consejo Nacl Invest Cient & Tecn, Fdn Miguel Lillo, Unidad Ejecutora Lillo, Miguel Lillo 251, RA-4000 San Miguel De Tucuman, Tucuman, Argentina Univ Koblenz Landau, Inst Integrated Sci, Dept Biol, Univ Str 1, D-56070 Koblenz, Germany Univ Fed Rural Rio De Janeiro, Inst Biol, Dept Biol Anim, Caixa Postal 74524, BR-23851970 Seropedica, RJ, Brazil Consejo Nacl Invest Cient & Tecn, Museo Argentino Ciencias Nat Bernardino Rivadavia, Div Herpetol, Angel Gallardo 470,C1405DJR, Buenos Aires, DF, Argentina Univ Buenos Aires, Fac Ciencias Exactas & Nat, Dept Biodiversidad & Biol Expt, Buenos Aires, DF, Argentina Univ Estadual Paulista, Inst Biociencias, Dept Biodiversidade, Av 24A 1515, BR-13506900 Rio Claro, SP, Brazil Univ Estadual Paulista, Inst Biociencias, Ctr Aquicultura, Av 24A 1515, BR-13506900 Rio Claro, SP, Brazil Univ Estadual Paulista, Inst Biociencias, Lab Herpetol, Campus Litoral Paulista, BR-11330900 Sao Vicente, SP, Brazil FAPESP: 2013/20423-3 FAPESP: 2017/26162-8 FAPESP: 2003/10335-8 FAPESP: 2011/50146-6 FAPESP: 2018/15425-0 FAPESP: 2012/10000-5 FAPESP: 2013/50741-7 FAPESP: 2007/57067-9 FAPESP: 2012/12500-5 CNPq: 167387/20170 CNPq: 155198/2018-1 CNPq: 476789/2009-5 CNPq: 306823/2017-9 CNPq: 140412/2008-5 CNPq: 150377/2012-6 CNPq: 150122/2014-4 Fundacao O Boticario de Protecao a Natureza: 0991_20132 Fundacao de Amparo a Pesquisa da Bahia (FAPESB): 8951/2014 CAPES: 001 CAPES: 88881.133927/2016-01 CNPq: 140716/2016-5 FAPESP: 2014/50342-8 Agencia Nacional de Promocion Cientifica y Tecnologica (ANPCyT): PICT 2013-404 Agencia Nacional de Promocion Cientifica y Tecnologica (ANPCyT): 2015-820

Enclosed are the figures, tables, and supplementary digital material of the manuscript entitled "Evidence of Absence Treated as Absence of Evidence: The Effects of Variation in the Number and Distribution of Gaps Treated as Missing Data on the Results of Standard Maximum Likelihood Analysis." See the README files (in Markdown and PDF format) for additional details., Funding was provided by the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP 2012/10000-5, 2013/09598-8, 2015/18654-2).

Ikakogi is a behaviorally and morphologically intriguing genus of glassfrog. Using tadpole morphology, vocalizations, and DNA, a new species is described from the Sierra Nevada de Santa Marta (SNSM), an isolated mountain range in northern Colombia. The new taxon is the second known species of the genus Ikakogi and is morphologically identical to I. tayrona (except for some larval characters) but differs by its genetic distance (14.8% in mitochondrial encoded cytochrome b MT-CYB; ca. 371 bp) and by the dominant frequency of its advertisement call (2928-3273 Hz in contrast to 2650-2870 Hz in I. tayrona). They also differ in the number of lateral buccal floor papillae, and the position of the buccal roof arena papillae. Additionally, the new species is differentiated from all other species of Centrolenidae by the following traits: tympanum visible, vomerine teeth absent, humeral spines present in adult males, bones in life white with pale green in epiphyses, minute punctuations present on green skin dorsum, and flanks with lateral row of small, enameled dots that extend from below eye to just posterior to arm insertion. We describe the external and internal larval morphology of the new species and we redescribe the larval morphology of Ikakogi tayrona on the basis of field collected specimens representing several stages of development from early to late metamorphosis. We discuss the relevance of larval morphology for the taxonomy and systematics of Ikakogi and other centrolenid genera. Finally, we document intraspecific larval variation in meristic characters and ontogenetic changes in eye size, coloration, and labial tooth-rows formulas, and compare tadpoles of related species. Ikakogi tayrona has been proposed as the sister taxon of all other Centrolenidae; our observations and new species description offers insights about the ancestral character-states of adults, egg clutches, and larval features in this lineage of frogs.

Background Lizards are excellent models to study the adaptations of the visual system to different scenarios, and surface-dwelling representatives have been relatively well studied. In contrast, very little is known about the functional anatomy of the eyes of fossorial lineages, and properties such as the light transmission by the ocular media have never been characterised in any fossorial species. Some lizards in the family Gymnophthalmidae endemic to the sand dunes of North Eastern Brazil have evolved sand-burrowing habits and nocturnal activity. Lizards in the sister group to Gymnophthalmidae, the family Teiidae, have decidedly diurnal and epigeal lifestyles, yet they are equally poorly known in terms of visual systems. We focussed on the eye anatomy, photoreceptor morphology and light transmittance properties of the ocular media and oil droplets in the gymnophthalmid Calyptommatus nicterus and the teiid Ameivula ocellifera. Results The general organisation of the eyes of the fossorial nocturnal C. nicterus and the epigeal diurnal A. ocellifera is remarkably similar. The lenses are highly transmissive to light well into the ultraviolet part of the spectrum. The photoreceptors have the typical cone morphology, with narrow short outer segments and oil droplets. The main difference between the two species is that C. nicterus has only colourless oil droplets, whereas A. ocellifera has colourless as well as green-yellow and pale-orange droplets. Conclusions Our results challenge the assumption that fossorial lizards undergo loss of visual function, a claim that is usually guided by the reduced size and external morphology of their eyes. In the case of C. nicterus, the visual system is well suited for vision in bright light and shows specialisations that improve sensitivity in dim light, suggesting that they might perform some visually-guided behaviour above the surface at the beginning or the end of their daily activity period, when light levels are relatively high in their open dunes habitat. This work highlights how studies on the functional anatomy of sensory systems can provide insights into the habits of secretive species.

Ambient mass spectrometry is useful for analyzing compounds that would be affected by other chemical procedures. Poison frogs are known to sequester alkaloids from their diet, but the sequestration pathway is unknown. Here, we describe methods for whole-body cryosectioning of frogs and use desorption electrospray ionization mass spectrometry imaging (DESI-MSI) to map the orally administered alkaloid histrionicotoxin 235A in a whole-body section of the poison frog Dendrobates tinctorius. Our results show that whole-body cryosectioning coupled with histochemical staining and DESI-MSI is an effective technique to visualize alkaloid distribution and help elucidate the mechanisms involved in alkaloid sequestration in poison frogs.

The transmittance properties of the cornea, lens and humours of vertebrates determine how much light across the visible spectrum reaches the retina, influencing sensitivity to visual stimuli. Amphibians are the only vertebrate class in which the light transmittance of these ocular media have not been thoroughly characterised, preventing large-scale comparative studies and precise quantification of visual stimuli in physiological and behavioural experiments. We measured the ocular media transmittance in some commonly used species of amphibians (the bufonids Bufo bufo and Rhinella ornata and the ranids Lithobates catesbeianus and Rana temporaria) and found low transmittance of short wavelength light, with ranids having less transmissive ocular media than bufonids. Our analyses also show that these transmittance properties have a considerable impact on photoreceptor spectral sensitivity, highlighting the need to incorporate this type of measurements into the design of stimuli for experiments on visual function.

To address the rapid and massive loss of biodiversity worldwide, scientific research must inform agile decision-making. The political leaders of Brazil, the country with the planet's greatest biological wealth ([ 1 ][1]), continue to undermine this goal. In 2001, citing the laudable objective of

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 morphological evidence that S. platycephalus and S. orophilus are conspecific, with S. orophilus being a junior synonym of S. platycephalus. Fil: de Araujo Vieira, Katyuscia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina Fil: Caramaschi, Ulisses. Universidade Federal do Rio de Janeiro; Brasil Fil: Grillitsch, Heinz. Natural History Museum Vienna; Austria Fil: Grant, Taran. Universidade de Sao Paulo; Brasil Fil: Faivovich, Julián. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina

We evaluate the monophyly and phylogenetic relationships of the Pristimantis leptolophus species group and describe its external morphology, osteology, and some myological characteristics. We also compare the P . leptolophus species group to other related species groups. The P . leptolophus group is not monophyletic due to the inclusion of P. acatallelus , formerly believed to be part of the P. devillei group. The revised P. leptolophus group is composed of nine named species and six unnamed species. Based on our results, we recognize a new species group, the P . boulengeri species group, composed of eight species, many of which were previously assigned to the P. lacrimosus species group.

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 Odontophrynus + Macrogenioglottus. The character-states observed in O. cultripes support conflicting phylogenetic positions within Odontophrynus. A comparison of some novel character-states with a diverse sample of burrowing taxa suggests that some modifications of the foot musculature might be involved in digging. Fil: Blotto Acuña, Boris Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; Argentina. Universidade de Sao Paulo; Brasil Fil: Pereyra, Martín Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; Argentina Fil: Faivovich, Julián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina Fil: Dos Santos Dias, Pedro Henrique. Universidade de Sao Paulo; Brasil Fil: Grant, Taran. Universidade de Sao Paulo; Brasil

The amount of short wavelength (ultraviolet (UV), violet and blue) light that reaches the retina depends on the transmittance properties of the ocular media, especially the lens, and varies greatly across species in all vertebrate groups studied previously. We measured the lens transmittance in 32 anuran amphibians with different habits, geographical distributions and phylogenetic positions and used them together with eye size and pupil shape to evaluate the relationship with diel activity pattern, elevation and latitude. We found an unusually high lens UV transmittance in the most basal species, and a cut-off range that extends into the visible spectrum for the rest of the sample, with lenses even absorbing violet light in some diurnal species. However, other diurnal frogs had lenses that transmit UV light like the nocturnal species. This unclear pattern in the segregation of ocular media transmittance and diel activity is shared with other vertebrates and is consistent with the absence of significant correlations in our statistical analyses. Although we did not detect a significant phylogenetic effect, closely related species tend to have similar transmittances, irrespective of whether they share the same diel pattern or not, suggesting that anuran ocular media transmittance properties might be related to phylogeny.

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 Atlantic Forest of Brazil and adjacent Argentina and Paraguay, have three patterns of vocal sac morphology—that is, single, subgular; paired, lateral; and absent. The submandibular musculature and structure of the vocal sac mucosa (the internal wall of the vocal sac) of exemplar species of this family and relatives were studied. In contrast to previous accounts, we found that all species of Crossodactylus and Hylodes possess paired, lateral vocal sacs, with the internal mucosa of each sac being separate from the contralateral one. Unlike all other frogs for which data are available, the mucosa of the vocal sacs in these genera is not supported externally by the mm. intermandibularis and interhyoideus. Rather, the vocal sac mucosa projects through the musculature and is free in the submandibular lymphatic sac. The presence of paired, lateral vocal sacs, the internal separation of the sac mucosae, and their projection through the m. interhyoideus are synapomorphies of the family. Furthermore, the specific configuration of the m. interhyoideus allows asymmetric inflation of paired vocal sacs, a feature only reported in species of these diurnal, stream-dwelling frogs. Fil: Elías Costa, Agustín Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina Fil: Montesinos, Rachel. Universidade de Sao Paulo; Brasil Fil: Grant, Taran. Universidade de Sao Paulo; Brasil Fil: Faivovich, Julián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina

Riama is the most speciose genus of the Neotropical lizard family Gymnophthalmidae. Its more than 30 montane species occur throughout the northern Andes, the Cordillera de la Costa (CC) in Venezuela, and Trinidad. We present the most comprehensive phylogenetic analysis of Riama to date based on a total evidence (TE) approach and direct optimization of molecular and morphological evidence. Analyses use DNA sequences from four loci and 35 phenotypic characters. The dataset consists of 55 ingroup terminals representing 25 of the 30 currently recognized species of Riama plus five undescribed taxa, including an endemic species from the Sierra Nevada de Santa Marta (SNSM) in Colombia, and 66 outgroup terminals of 47 species. Analysis results in a well-supported hypothesis in which Riama is polyphyletic, with its species falling into three clades. The Tepuian Anadia mcdiarmidi nests within one clade of Riama, and the recently resurrected Pantodactylus nests within Cercosaura. Accordingly, we propose a monophyletic taxonomy that reflects historical relationships. Analysis of character evolution indicates that the presence/absence of prefrontals—a cornerstone of the early genus-level taxonomy of cercosaurines—is optimally explained as having been plesiomorphically present in the most recent common ancestor of Cercosaurinae and lost in that of the immediately less inclusive clade. Multiple independent reversals to present and subsequent returns to absent occur within this clade. To evaluate the impact of phenotypic evidence on our results, we compare our TE results with results obtained from analyses using only molecular data. Although phenotypic evidence comprises only 1.2% of the TE matrix, its inclusion alters both the topology and support values of the clades that do not differ. Finally, current phylogenetic evidence reveals a SNSM–CC–Trinidad–tepuis biogeographical link. We hypothesize that an ancient connection facilitated the exchange of species between the SNSM and the CC.

For most pond-breeding anurans, movement is fundamental for foraging, reproduction, avoidance of adverse environmental conditions, and predator avoidance and escape. Although the influence...

Nuptial pads are patches of thickened skin, associated with sexually dimorphic skin glands, present only in the thumbs and fingers of male anurans, and hence considered dimorphic sexual characters. Despite the morphological description for many species, the evolution and function of nuptial pads are still unclear. In this study, we describe the presence of nuptial-pad–like structures in females of two species of Melanophryniscus and compare their morphology and histology to males' nuptial pads. The epidermal modifications found in females are conical papillary epidermal projections, similar to the structures found in males; however, the density of these projections in males is twice the average found in females. Also, the nuptial-pad–like structure found in females cannot be considered an actual nuptial pad, because there are no specialized skin glands associated with the structure. This study brings the first records of epidermal modification in females of Melanophryniscus and provides the descr...

Most anurans possess a tympanic middle ear (TME) that transmits sound waves to the inner ear; however, numerous species lack some or all TME components. To understand the evolution of these structures, we undertook a comprehensive assessment of their occurrence across anurans and performed ancestral character state reconstructions. Our analysis indicates that the TME was completely lost at least 38 independent times in Anura. The inferred evolutionary history of the TME is exceptionally complex in true toads (Bufonidae), where it was lost in the most recent common ancestor, preceding a radiation of >150 earless species. Following that initial loss, independent regains of some or all TME structures were inferred within two minor clades and in a radiation of >400 species. The reappearance of the TME in the latter clade was followed by at least 10 losses of the entire TME. The many losses and gains of the TME in anurans is unparalleled among tetrapods. Our results show that anurans and especially bufonid toads, are an excellent model to study the behavioural correlates of earlessness, extratympanic sound pathways and the genetic and developmental mechanisms that underlie the morphogenesis of TME structures.

The dendrobatid genus Silverstoneia is a clade of forest-dwelling frogs that share small adult size ( II, male nurse frogs (known in four species), and larvae possessing an umbelliform oral disc with few to many submarginal papillae and medially emarginate posterior labium (also known in four species). The clade is distributed from Costa Rica to southern Departamento del Valle del Cauca in western Colombia and includes eight species, five of which are described herein as new species. As in all species of Dendrobatoidea, in Silverstoneia the distal tendon of insertion of the m. semitendinosus inserts dorsad to the distal tendon of the mm. gracilis complex and is strapped to the dorsal edge of the inner surface of the mm. gracilis complex by a unique binding tendon. The species of Silverstone...

We describe a remarkable new species of monophyletic genus Hyloscirtus from northeastern Peru. The presence of an enlarged, curved, and protruding prepollical spine; hypertrophied forelimbs; large, thick supracloacal flap and supratympanic fold; large size; nuptial pad absent and iris dark red diagnose this species. We hypothesize that the new species is closely related to H. condor and H. tapichalaca of southern Ecuador due to the apparently synapomorphic occurrence in these species of an enlarged, curved prepollical spine, and small, conical vomerine odontophore processes with 3–6 prominent teeth each without contact between these. Additional research explicitly incorporating H. diabolus new species in a phylogenetic analysis is required to further test our hypothesis and provide a better understanding of the evolution of morphological attributes described herein. Finally we discuss some aspects concerning the taxonomy of the genus Hyloscirtus.