Flora Acuña Juncá

Unexpected phylogenetic positions of the genera Rupirana and Crossodactylodes reveal insights into the biogeography and reproductive evolution of leptodactylid frogs.

Despite major progress in deciphering the amphibian tree of life by molecular phylogenetics, we identified two questions remaining to be answered regarding relationships within Hyloidea, the clade of South American origin that comprises most extant anuran diversity. A few genera like Rupirana and Crossodactylodes have enigmatic phylogenetic positions, and relationships among major lineages within some families like Leptodactylidae remain ambiguous. To resolve these specific questions we used two approaches (1) a complete matrix approach representing >6.6 kb, including most major Hyloidea lineages (61 terminals) combining different methods of phylogenetic reconstruction and measures of node support; and (2) a supermatrix approach >11.6 kb with a focus on Leptodactylidae. Both Rupirana and Crossodactylodes are unambiguously grouped with Paratelmatobius and Scythrophrys. The clade comprising these four genera is named Crossodactylodinae and embedded within Leptodactylidae. Crossodactylodinae is moderately supported as sister group of Leptodactylinae from (1) and as the sister group of the other Leptodactylidae from (2) with low support. Genera within Crossodactylodinae are scattered along a north-south axis in the Atlantic forest and their origins are very ancient (Paleocene). Such results stress the importance of the northern Atlantic forest in terms of conservation. Moreover, the position of Pseudopaludicola, which is well supported as the sister group to all other Leiuperinae, suggests that foam-nest building may have arisen independently in Leptodactylinae and Leiuperinae. Moreover, in spite of being of similar age, foam-nest builders are more widespread than nonfoam-nest breeders and have higher species diversity. Nevertheless, the bulk of the diversity within foam-nest breeders arose some 20 Myr later than the character itself.

Diversidade e uso de hábitat por anfíbios anuros em duas localidades de Mata Atlântica, no norte do estado da Bahia

A composicao e abundância da anurofauna, bem como a distribuicao das especies em locais de reproducao, foram determinados em duas localidades na Mata Atlântica, norte do estado da Bahia. A Serra da Jiboia (SJ) e um macico montanhoso com altitude maxima de 800 m, localizada em uma area de transicao entre Caatinga e Mata Atlântica. A Reserva Sapiranga (RS) e um fragmento de mata a 200 m de altitude e localizado proximo ao litoral. Nas duas localidades, os seguintes habitats foram amostrados: folhedo/sub-bosque, bromelias terricolas, pocas temporarias, pocas permanentes e riachos. Ao longo de 10 meses de 2001, foram realizadas coletas noturnas, totalizando 14 noites de amostragem na Reserva Sapiranga (RS) e 12 na Serra da Jiboia (SJ). Um total 45 especies foram registradas, sendo que apenas sete foram comuns as duas localidades. Na SJ, mais especies (n = 14) estiveram associadas ao folhedo/sub-bosque do que aos outros sitios reprodutivos, incluindo Frostius pernambusencis e Eleutherodactylus ramagii, duas das tres especies mais abundantes nessa localidade. Na RS, as pocas temporarias foram os habitats que apresentaram maior numero de especies (n = 18), incluindo tambem as duas mais abundantes (Leptodactylus natalensis e Scinax sp. grupo ruber) nessa localidade. Estas diferencas podem ser atribuidas as diferencas de altitude, vegetacao e condicoes do folhedo nas duas localidades. Neste estudo foi registrado o aumento na area de distribuicao de Leptodactylus mystaceus, Eleutherodactylus bilinetus, E. vinhai, Sphaenorhynchus prasinus e Phyllodytes melanomystax.

ADVERTISEMENT CALLS OF FOUR HYLID FROGS FROM THE STATE OF BAHIA, NORTHEASTERN BRAZIL (AMPHIBIA, ANURA, HYLIDAE)

Abstract We describe the advertisement calls of Dendropsophus branneri, Phyllodytes melanomystax, and Scinax agilis, and present new information on the advertisement call of Scinax auratus. We also describe the territorial call of P. melanomystax. We provide the power spectrums, audiospectrograms, and waveforms of all calls. Vocalizations were recorded in the Municipalities of Camaçari, Elísio Medrado, Feira de Santana, and Mata de São João, State of Bahia, Brazil. Based on the advertisement call characteristics of these species, we discuss some aspects related to their taxonomy.

Effects of temperature and volume of water on the growth and development of tadpoles of Pleurodema diplolister and Rhinella granulosa (Amphibia: Anura)

The capacity of tadpoles to reduce their metamorphosis time and body size in response to fluctuations in environmental variables of temporary ponds has been recorded in field and laboratory studies. The main alterations in this habitat are related to the decrease of the water level and increase in temperature. However, few studies tried to dissociate the effect of these two variables. The aim of the present study was to analyze simultaneously the effects of water volume reduction and temperature on the development and growth in tadpoles of Pleurodema diplolister (Peters, 1870) and Rhinella granulosa (Spix, 1824) - species that use temporary ponds for reproduction. The tadpoles of these two species were subject to four treatments: (1) constant volume of water of 2000 ml and constant temperature of 26oC; (2) gradually decreasing water volume from 2000 ml to 200 ml or 150 ml and constant temperature of 26 oC; (3) Constant water volume as in (1) and constant temperature of 30 oC or 33 oC and (4) Decreasing water volume (as above) and constant temperature as in the treatment (3). There was no interaction between both tested variables on the growth and development of tadpoles of both species. Tadpoles of P. diplolister and R. granulosa responded to high temperature by decreasing development time. Tadpoles responded to decreasing volume of water by metamorphosing into smaller size. Tadpoles of P. diplolister maintained at 30oC showed growth reduction. Tadpoles of R. granulosa increased their body size when subject to the treatment at 30oC.

Micro-Habitat Influence on the Advertisement Call Structure and Sound Propagation Efficiency of Hypsiboas crepitans (Anura: Hylidae)

Abstract Acoustic signals are the main communication vehicle for most anuran species, and males typically use advertisement calls to attract females and to interact with other males in a chorus. The role of the environment in the evolution of the advertisement call is still largely unknown, and the recognition of different selective pressures may improve our understanding of anuran communication system. The aim of this study was to investigate the effect of micro-habitat at calling sites on advertisement call structure and propagation in a population of the treefrog Hypsiboas crepitans. Males of this species typically call from elevated sites in vegetation or from sites where their body is partially submerged in water. Our analysis of call parameters of males calling from these sites showed that both dominant frequency and pulse rate were significantly lower when males called partially submerged in water compared to males calling from elevated sites in vegetation. Both pulse rate and dominant frequency have been shown to be important in species recognition among anurans, and they play a role in sexual selection and sound propagation. Our analysis of the effect of calling site (elevated or partially submerged) on signal propagation showed that the efficiency of transmission did not differ between sites.

A New Species of the Scinax ruber Clade (Anura, Hylidae) from the Espinhaço Range, Northeastern Brazil

Abstract:  A new species belonging to the Scinax ruber clade, morphologically similar to S. cabralensis and S. rupestris, is described from the Municipality of Miguel Calmon, State of Bahia, northeastern Brazil. This locality belongs to the northern portion of the Espinhaço Range known as Chapada Diamantina, a semiarid region in central Bahia State. The new species can be distinguished from all congeners of the S. ruber clade by a combination of adult (size, morphology, color pattern, and advertisement call) as well as larval (external morphology, and oral cavity) characteristics. The description of this frog adds another species, and the first of the S. ruber clade, to those that are endemic to Chapada Diamantina.

Background noise as a selective pressure: stream-breeding anurans call at higher frequencies

Acoustic signals are an important part in the behaviour of many species and may play a key role in speciation. However, little is known about the importance of natural selection on the evolution of such signals. Acoustics signals are the main communication channel for most anuran species, and background noise from streams is a constant source of masking interference for species reproducing in these environments. Herein, we test if the noise of flowing water habitats has favoured advertisement calls with higher dominant frequencies in frogs. Phylogenetic generalized least square model analysis revealed a significant influence of reproductive environment and body size on dominant frequency, with no significant interaction between habitat and body size. While stream breeders call at higher dominant frequencies, this acoustic parameter is inversely correlated with body size in both environments. We discuss the biological consequences of long-term adaptive shift in this acoustic parameter and possible trade-offs with other evolutionary forces.

Redescription of Proceratophrys cristiceps (Müller, 1883) (Amphibia, Anura, Odontophrynidae), with Description of Two New Species without Eyelid Appendages from Northeastern Brazil

ABSTRACT. We redescribe Proceratophrys cristiceps and describe two new allied species, constituting the northernmost record of that group for the Atlantic Forest remnants. In addition to the morphometric differences, the characteristics of size, snout shape, head width, tympanum, interocular transverse crest of tubercles, canthal crest, frontoparietal crest, outer metacarpal tubercle, webbing formulae, inner metacarpal tubercle, and blotches on venter, were used to diagnose the species. The distribution of P. cristiceps is restricted to eastern Brasil, from the state of Rio Grande do Norte to the state of Bahia, and both new species are only known from the type locality in the state of Ceará.

Morphological changes in the female reproductive organs during mating in Colostethus stepheni and associated behaviour

Extended courtship and amplexus have been related either to readiness for spawning or to evaluation of the quality of egg-laying site. As preliminary observations revealed that a pair of C. stepheni can engage in two successive amplexi, an unusual pattern for dendrobatid frogs, we carried out experiments in the field to characterize this mating strategy. During the first hour after the first amplexus, we detect ovulation and changes in the oviduct morphology. The female could exhibit three different behavioural patterns, if disturbed after the first amplexus: remaining in the nest, leaving the nest and returning some minutes later, leaving the nest and subsequently enticed by their mate to another nearby nest. In cases where the male did not return for the second amplexus, the female sought another mate and engaged in a second amplexus.

A molecular phylogeny recovers Strabomantis aramunha Cassimiro, Verdade and Rodrigues, 2008 and Haddadus binotatus (Spix, 1824) (Anura: Terrarana) as sister taxa

The taxonomic and biogeographic affinities of Strabomantis aramunha from the Campos Rupestres of Brazil are intriguing. A unique skull morphology of females suggest affinities with the broad-headed eleutherodactylines of Northwestern South America in the genus Strabomantis. Male and juvenile morphology nonetheless suggest S. aramunha could be related to members of the recently described genus Haddadus from eastern Brazil. We assess the affinities of S. aramunha using molecular phylogenetic analyses of mitochondrial (12S, tRNAval, 16S, cyt b) and nuclear sequences (RAG-1and rhodopsin). Bayesian inference, likelihood, and parsimony analysis recover a highly supported clade with S. aramunha and H. binotatus as sister taxa. Accordingly, we transfer S. aramunha to Haddadus, and provide a new generic definition of the later. The distribution of species in Haddadus (highlands of the Espinhaço mountain Range and coastal eastern Brazil) is now concordant with the general pattern observed for other species in the area.