Climate change in the Central Amazon and its impacts on frog populations.

Frog population declines have already been observed in the central Amazon even for common species that are considered not to be in danger of extinction. The Amazon is close to its limit of tolerated deforestation, and parts of the forest have already been modified by climate change, which raises questions about how the fauna in these areas would adapt to climate changes by the middle and the end of this century. In this study we used population density data on seven species of Amazonian frogs and analyzed the relationship between the activity of these species and temperature, precipitation, and relative humidity. We also used the least-squares method with logarithmic models to assess whether climate change projected by the Intergovernmental Panel on Climate Change (IPCC) would be an indicator of the population dynamics of these species. Our results suggest that even common species may be may experience population declines and extinction in the next decades due to climate changes.

Tadpoles of Central Amazonia (Amphibia: Anura).

Amazonian lowland rainforests epitomize, as few other biomes, the terrestrial and freshwater biological diversity of our planet. We provide here a comprehensive description of the larval anurans of Central Amazonia, and their natural history. We base our analyses on fieldwork conducted in six terra-firme rainforest and two várzea floodplain sites during ~60 months between 1990 and 2013, complemented with an examination of museum specimens and a review of published literature. Ninety-nine species of anurans are known to occur in Central Amazonia. Of these, 84 species (85%) have a free-swimming exotrophic larva, six species (6%) have a terrestrial endotrophic larva, one species has a terrestrial exotrophic larva (1%) and another seven species (7%) have direct development of eggs into froglets. The life cycle of one species (1%) remains unknown. We formally describe and illustrate the larval stage of 68 species (i.e., 75% of the species with a known larval stage), five of them previously unkown and nineteen never described for Central Amazonia. We compile, review and update information on species natural history including reproductive modes, habitat use, phenology, and species interactions including diet, predators, competitors and parasites. Finally, we assessed the ecomorphological diversity in the region by the application of a system inspired in Altig & Johnston (1989), later updated by Altig & McDiarmid (1999), which recognizes tadpole guilds based on a combination of morphological and natural history data. Basic scientific information presented in this monograph provide the essential background for further studies on the ecological and evolutionary forces shaping anuran Amazonian assemblages, and their conservation.

The Program for Biodiversity Research in Brazil: The role of regional networks for biodiversity knowledge, dissemination, and conservation.

The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes.

Phylogenetic relationships of the poorly known treefrog Boana hobbsi (Cochran amp; Goin, 1970) (Anura: Hylidae), systematic implications and remarks on morphological variations and geographic distribution.

Boana hobbsi is a poorly known hylid frog currently placed within the Boana punctata group. Yet, morphological, ecological and bioacoustic traits do not support this placement, with no molecular data being available to date to test this hypothesis. Based on newly collected mitochondrial DNA sequences, morphological data review and field observations, we provide new insight into the phylogenetic relationships, morphological variations and geographic distribution of B. hobbsi. Our findings reveal that B. hobbsi is nested (with strong support) within the Boana benitezi group, recovering once more a polyphyletic Boana punctata group. Supported by this new genetic, morphological and ecological evidence, we propose a new taxonomic arrangement which includes B. hobbsi as a member of the Boana benitezi group. Furthermore, we emphasize the importance of conducting biological inventories in remote Amazonian areas, where many taxonomic and geographic knowledge gaps persist with regards to Amphibian diversity.

The tadpole of Amazophrynella teko (Anura: Bufonidae) from the eastern Amazon, Brazil.

The genus Amazophrynella Fouquet, Recoder, Teixeira, Cassimiro, Amaro, Camacho, Damasceno, Carnaval, Moritz, and Rodrigues, is represented by 12 nominal species and distributed in the Amazon region of Brazil, Bolivia, Colombia, Ecuador, Guyana, French Guiana, Peru, and Venezuela (Frost 2020). In the last eight years, ten species from this genus have been described. However, despite the wide distribution and diversity of these species, only the tadpole of Amazophrynella manaos Rojas, Carvalho, Ávila, Farias, and Hrbek from the Brazilian Amazon (Menin et al. 2014) and A. siona Rojas, Fouquet, Ron, Hernández-Ruz, Melo-Sampaio, Chaparro, Vogt, Carvalho, Pinheiro, Ávila, Farias, Gordo, and Hrbek from Ecuador have been formally described (Duellman Lynch 1969; Rojas et al. 2018). Literature about tadpole morphology, reproduction, and bioacoustics of Amazophrynella is scarce and necessary to a comprehensive taxonomic classification (Kaefer et al. 2019). Herein, we describe the tadpole of the recently described species Amazophrynella teko Rojas, Fouquet, Ron, Hernández-Ruz, Melo-Sampaio, Chaparro, Vogt, Carvalho, Pinheiro, Ávila, Farias, Gordo, and Hrbek, found in the northeastern Amazon, in the State of Amapá, Brazil, and in French Guiana.

Description of the tadpole of Dendropsophus haraldschultzi (Bokermann, 1962) (Anura: Hylidae), with comments on reproductive biology.

The genus Dendropsophus Fitzinger contains 108 recognized species (Frost 2020) distributed in nine species groups according to Faivovich et al. (2005). However, recent phylogenetic analysis recognized the presence of nonmonophyletic groups (e.g., Wiens et al. 2010; Fouquet et al. 2011; Motta et al. 2012; Jansen et al. 2019) suggesting that the relationships among species of Dendropsophus require careful revision. Species of this genus are distributed in the tropical and subtropical South America, including Trinidad, southward to northern Argentina and Uruguay and northward to Central America and tropical southern Mexico (Duellman et al. 2016; Frost 2020). Dendropsophus haraldschultzi (Bokermann) was described in the area of Santa Rita do Weill, municipality of São Paulo de Olivença, Amazonas State, Brazil. Adult individuals of D. haraldschultzi are small sized frogs (males 18-22 mm and females 22-25 mm; Rodríguez Duellman 1994) with tuberculate skin on dorsal surfaces, denser on the head. They are found near open ponds and permanent large streams or in floating meadows along the Amazon river (Bokermann 1962; Rodríguez Duellman 1994; Böning et al. 2017) and have been also found along the Amazon River Valley in the Brazilian states of Pará and Amapá (Missassi et al. 2017), and in Peru and Colombia. Bokermann (1962) and later authors (e.g., Lutz 1973) considered this species without evident taxonomic affinities. Currently, D. haraldschulzi is not assigned to any species group within the genus (Faivovich et al. 2005).

Effect of environmental parameters on squamate reptiles in an urban forest fragment in central Amazonia

The increasing urbanization of the Amazonian biome has promoted the creation of several forest fragments surrounded by an urban matrix, but the relationship of animal assemblages to the urban environment, especially in forest fragments, is poorly known. Here we aimed to 1) determine the composition of the squamate fauna of the largest urban forest fragment from central Amazonia, in the Brazilian city of Manaus, and 2) evaluate the influence of environmental parameters on assemblage diversity. We sampled 10 standardized riparian plots through visual search in six surveys between 2008/09 and 2015, totaling 360 observer-hours. We found 15 species of lacertoids (lizards and amphisbaenians) and seven species of snakes through active search. After considering occasional encounters and search in museum collections, we recorded a total of 24 lacertoid and 22 snake species. Multiple regression models indicated that species richness and abundance of individuals increased with the distance from the edge of the fragment, while other structural parameters of the environment did not affect the assemblage. We conclude that this forest fragment 1) consists of a subset of the regional species pool, and 2) undergoes reduction of species richness and abundance of individuals from the center to the borders. This and additional urban forest fragments should be continually monitored in order to evaluate their long-term role in maintaining the tropical biodiversity. (AU)

Author Correction: Sole coloration as an unusual aposematic signal in a Neotropical toad.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Anuran diversity in urban and rural zones of the Itacoatiara municipality, central Amazonia, Brazil / Diversidade de anuros nas zonas urbana e rural de Itacoatiara, Amazônia central, Brasil

Few studies in the Amazon region have evaluated anuran diversity in urban forest fragments or in areas with differing degrees of anthropogenic impact. We determined the composition and abundance of the anurofauna in urban and rural sites within the municipality of Itacoatiara in central Amazonia, Brazil. Specimens were sampled from January 2012 to May 2013 in 10 urban sites and five rural sites. A total of 1,538 anurans (930 in rural sites and 608 in urban sites) were recorded, belonging to 29 species in five families. Species richness was higher in rural sites, with 10 exclusive species. All species found in urban sites were also found in rural sites, however, species abundance varied considerably between the habitats. Sampling- and individual-based rarefaction curves showed a tendency toward stabilization of species richness only in the urban sites. We concluded that the anuran assemblages in the urban sites are depauperate due to the absence of many species associated to pristine terra firme or várzea and igapó forests. Habitat loss and quality degradation in urban landscapes are the main factors threatening amphibian diversity. The anuran assemblages in our study areas were similar to those recorded in other Amazonian habitats. Conservation measures involving anurans in this region should consider the preservation of habitat mosaics, including both pristine terra firme, várzea and igapó forests. (AU)

Poucos estudos avaliaram a diversidade de anuros em fragmentos florestais urbanos ou em áreas com diferentes graus de impacto antrópico na Amazônia. Neste estudo foi determinada a composição e abundância de anuros em áreas urbanas e rurais no município de Itacoatiara, na Amazônia central, Brasil. Anuros foram amostrados entre janeiro de 2012 e maio de 2013 em 10 locais na área urbana e cinco na área rural. Um total de 1.538 indivíduos (930 na área rural e 608 na área urbana) foram registrados, compreendendo 29 espécies e cinco famílias. A área rural apresentou maior riqueza de espécies, com 10 espécies exclusivas. Todas as espécies identificadas na área urbana também foram encontradas na área rural, mas a abundância das espécies entre ambas áreas variou consideravelmente. Curvas de rarefação por amostragem e por número de indivíduos tenderam à estabilização na riqueza de espécies somente na área urbana. Concluímos que a comunidade de anuros na área urbana está empobrecida devido à ausência de muitas espécies associadas à ambientes inalterados de florestas de terra firme, várzea e igapó. A degradação da qualidade e a perda de habitat nas paisagens urbanas são os principais fatores que ameaçam a diversidade de anfíbios. A comunidade de anuros registrada neste estudo foi similar às de outros habitats na Amazônia. Medidas de conservação envolvendo anuros nesta região devem considerar a preservação de um mosaico de habitats que inclua áreas naturais de floresta de terra firme, várzea e igapó.(AU)

Intraspecific and interspecific trait variability in tadpole meta-communities from the Brazilian Atlantic rainforest.

A better understanding of species coexistence and community dynamics may benefit from more insights on trait variability at the individual and species levels.Tadpole assemblages offer an excellent system to understand the relative influence of intraspecific and interspecific variability on community assembly, due to their high phenotypic plasticity, and the strong influence that environmental variables have on their spatial distribution and individual performance.Here, we quantified the intraspecific and interspecific components of tadpoles' trait variability in order to investigate their relative role in shaping tadpole communities.We selected eight functional traits related to microhabitat use, foraging strategies, and swimming ability. We measured these traits on 678 individuals from 22 species captured in 43 ponds in the Atlantic Forest. We used single- and multitrait analyses to decompose trait variability. To explore the action of external and internal filtering on community assembly, we used a variance decomposition approach that compares phenotypic variability at the individual, population, community and regional levels.On average, 33% of trait variability was due to within-species variation. This decomposition varied widely among traits. We found only a reduced effect of external filtering (low variation in the height of the ventral fin within ponds in comparison to the total variation), whereas the internal filtering was stronger than expected. Traits related to the use of different microhabitats through the water column were generally less variable than traits related to swimming ability to escape of predators, with tail traits being highly variable within species.Our study highlights the importance of incorporating both intraspecific and interspecific, trait differences and of focusing on a diversity of traits related to both stabilizing niche and fitness differences in order to better understand how trait variation relates to species coexistence.

Sole coloration as an unusual aposematic signal in a Neotropical toad.

Many animals have evolved remarkable strategies to avoid predation. In diurnal, toxic harlequin toads (Atelopus) from the Amazon basin, we find a unique colour signal. Some Atelopus populations have striking red soles of the hands and feet, visible only when walking. When stationary, the toads are hard to detect despite their yellow-black dorsal coloration. Consequently, they switch between high and low conspicuousness. Interestingly, some populations lack the extra colour display of the soles. We found comprehensive support that the red coloration can act as an aposematic signal directed towards potential predators: red soles are significantly more conspicuous than soles lacking red coloration to avian predators and the presence of the red signal significantly increases detection. Further, toads with red soles show bolder behaviour by using higher sites in the vegetation than those lacking this signal. Field experiments hint at a lower attack risk for clay models with red soles than for those lacking the signal, in a population where the red soles naturally occur. We suggest that the absence of the signal may be explained by a higher overall attack risk or potential differences of predator community structure between populations.

The tadpole of Elachistocleis helianneae Caramaschi, 2010 (Anura: Microhylidae).

The neotropical genus Elachistocleis Parker comprises 18 described species [including Elachistocleis ovalis (Schneider) which is considered a nomen dubium by Caramaschi (2010), with pending revision]. This genus is distributed in Central America and most of South America, from Panama and Trinidad to southern Paraguay, including central Argentina, Uruguay, Venezuela, Colombia, Bolivia, Guyana, Surinam, French Guiana, and Brazil (Marinho et al. 2018; Frost 2019). Currently, the tadpoles of ten species have been described and/or figured: Elachistocleis bicolor (Guérin-Méneville), E. cesarii (Miranda-Ribeiro), E. erythrogaster Kwet and Di-Bernardo, E. haroi Pereyra, Akmentins, Laufer and Vaira, E. muiraquitan Nunes-de-Almeida and Toledo, E. ovalis, E. panamensis (Dunn, Trapido and Evans), E. pearsei (Ruthven), E. surinamensis (Daudin), and Elachistocleis sp. (Kenny 1969; Williams & Gudynas 1987; Kwet & Di-Bernardo 1998; Duellman 2005; Lynch 2006; Rossa-Feres & Nomura 2006; Vera Candioti 2006; Magalhães et al. 2012; Pereyra et al. 2013).

When the unknown lives next door: a study of central Amazonian anurofauna.

The number of species of anurans in the Amazon is highly underestimated with new studies reporting the discovery of a large number of species every year. This advance in the discovery of biodiversity is due to the use of molecular tools, especially 16S rRNA gene barcoding, which is used to identify species and discover cryptic lineages. Few anurans of the central Amazon have molecular sequence data available in public databases, which contrasts with the considerable species richness of this biome. The aim of the present study was to test for the presence of cryptic species using the mPTP delimitation algorism. We morphologically identified 26 species, of which 23 were confirmed molecularly with the remaining three species identified as other congeneric species, since sequences with the same epithet do not exist in GenBank. Of these 23 species, nine contained one lineage restricted to central Amazon. This represents an underestimate of 39% in the taxonomic diversity in our sample. This is particularly surprising given that our sampling sites are among the best-studied regions of the central Amazon.

Intra-generic and interspecific karyotype patterns of Leptodactylus and Adenomera (Anura, Leptodactylidae) with inclusion of five species from Central Amazonia.

The genera Leptodactylus and Adenomera comprise 92 species distributed throughout the Neotropical region. These species have a modal diploid chromosome number 2n = 22. However, chromosome rearrangements are evident in the differentiation of five intra-generic groups in the genus Leptodactylus (L. fuscus, L. latrans, L. marmoratus (formally composed by the species of the genus Adenomera), L. melanonotus, L. pentadactylus), yet it is not clear if there is a karyotype pattern for each group. Aiming to understand the intra-generic and interspecific karyotype patterns of Leptodactylus and Adenomera, cytogenetic analyses were performed in A. andreae, L. macrosternum, L. pentadactylus, L. petersii, and L. riveroi using conventional staining, C-banding, nucleolus organizer region (NOR) and hybridization in situ fluorescent (FISH). The karyotype of Leptodactylus riveroi was described for the first time. Adenomera andreae had 2n = 26, while the remaining species 2n = 22. The NOR was found on pair No. 8 of A. andreae, L. macrosternum, L. pentadactylus, and L. riveroi, whereas L. petersii had it on pairs Nos. 6 and 10. These locations were confirmed by the FISH with 18S rDNA probe, except for pair No. 10 of L. petersii. The C-banding pattern was evident at the centromeres of chromosomes of all species and some interspecific variations were also observed. 2n = 22 was observed in the species of the L. latrans group, as well as in the intra-generic groups L. fuscus and L. pentadactylus; in the L. melanonotus group there were three diploid chromosome numbers 2n = 20, 22 and 24; and a larger variation in 2n was also evident in the L. marmoratus group.

The tadpole of Amazophrynella manaos Rojas, Carvalho, Gordo, Ávila, Farias and Hrbek, 2014 (Anura, Bufonidae) from the type locality and adjacent regions at Central Amazonia, Brazil.

The genus Amazophrynella, as currently recognized (Fouquet et al. 2012a, b), is represented by four nominal species (Frost 2014; Rojas et al. 2014) but the tadpoles of only one species, Amazophrynella minuta (Melin) from Ecuador, have been described (Duellman & Lynch 1969; Duellman 1978). Amazophrynella manaos Rojas, Carvalho, Gordo, Ávila, Farias and Hrbek, 2014 occurs in the leaf litter of terra firme forest in the southwestern part of the Brazilian Guiana region (Rojas et al. 2014). The tadpole of this species was briefly described in diagrammatic drawings by Hero (1990) as Dendrophryniscus minutus. Herein, we provide a detailed description of this tadpole based on individuals at 12 stages of development collected in five different sites, including the type locality, at Central Amazonia, Brazil.

Karyotypic diversity in seven Amazonian anurans in the genus Hypsiboas (family Hylidae).

BACKGROUND: Hypsiboas species have been divided into seven groups using morphological and genetic characters, but for most of the species, there is no cytogenetic information available. A cytogenetic analysis using conventional staining, C-banding, silver staining, and fluorescence in situ hybridization (FISH) with telomeric sequence probes were used to investigate the karyotype of seven Amazon species of the genus Hypsiboas belonging to the following intrageneric groups: H. punctatus (H. cinerascens), H. semilineatus (H. boans, H. geographicus, and H. wavrini), and H. albopunctatus (H. lanciformis, H. multifasciatus, and H. raniceps). The aim was to differentiate between the karyotypes and use the chromosomal markers to distinguish between the Hypsiboas groups. The data were compared with a previous phylogenetic proposal for these anurans. In addition, H. lanciformis, H. boans, and H. wavrini are described here for the first time, and we characterize the diploid numbers for H. cinerascens, H. geographicus, H. multifasciatus, and H. raniceps. RESULTS: The diploid number for all of the species analyzed was 24, with the exception of Hypsiboas lanciformis, which had 2n = 22 chromosomes. The constitutive heterochromatin distribution, nucleolar organizer region locations, and interstitial telomeric sites differed between the species. A hypothesis that the heterochromatic patterns are evolving is proposed, with the divergence of the groups probably involving events such as an increase in the heterochromatin in the species of the H. semilineatus group. The FISH conducted with the telomeric probes detected sites in the terminal regions of all of the chromosomes of all species. Interstitial telomeric sites were detected in three species belonging to the H. semilineatus group: H. boans, H. geographicus, and H. wavrini. CONCLUSION: The results of this study reinforce the complexity previously observed within the genus Hypsiboas and in the different groups that compose this taxon. More studies are needed focusing on this group and covering larger sampling areas, especially in the Brazilian Amazon, to improve our understanding of this fascinating and complex group.

Diversidade de anfíbios e répteis Squamata na região do baixo rio Purus, Amazônia Central, Brasil / Diversity of amphibians and Squamata reptilians from lower Purus River Basin, Central Amazonia, Brazil

A região do baixo rio Purus na Amazônia Central - Brasil representa uma área de relevante interesse para conservação de anfíbios e répteis. No entanto, há pouca informação disponível sobre estes grupos taxonômicos para áreas de florestas de terra firme e florestas de várzea, principais paisagens nesta região. Nesse estudo, realizamos uma amostragem ampla em esforço e área, em dois períodos: 2004-2005 e 2009-2010. Utilizamos técnicas complementares eficientes na amostragem da herpetofauna em florestas tropicais: procura ativa limitada por tempo (PLT), armadilhas de interceptação e queda (AIQ) e armadilhas de interceptação com funis duplos (AIF). Foram registradas 160 espécies, sendo 75 de anfíbios (73 anuros e dois gimnofionos) e 85 de répteis (34 lagartos e 51 serpentes). O registro do anuro Dendropsophus allenorum foi o primeiro para o Brasil. Comparando a eficiência dos métodos de coleta, a busca ativa por coletores capacitados (PLT) foi o método mais eficaz na amostragem da herpetofauna; seguido das AIQ, eficientes na captação de anuros terrícolas e lagartos de serrapilheira nas florestas de terra firme. Não utilizamos AIQ nas áreas de várzea por estas terem solos hidricamente saturados. As AIF, apesar de menos eficientes na amostragem de anuros e lagartos, foram eficazes na captura serpentes e facilmente adaptáveis aos solos hidromórficos das várzeas. Uma maior riqueza de espécies e famílias foi encontrada nas florestas de terra firme. As florestas de várzea tiveram uma marcante ausência de famílias fossoriais e de serrapilheira. No entanto, nas florestas de várzea encontramos um maior número de espécies de anuros arborícolas (Hylidae) e de lagartos heliotérmicos maiores (Teiidae). Entretanto, avaliando separadamente cada período de amostragem, a riqueza de espécies da herpetofauna torna-se similar entre os diferentes tipos de paisagens florestais, tendendo ser maior nas florestas de terra firme. Apesar de similares em número espécies, as florestas de terra firme e de várzea foram diferentes quanto ao conjunto das espécies. A diversidade complementar de anfíbios e répteis Squamata entre florestas de terra firme e de várzea (diversidade beta-β), paisagens de maior abrangência local, possivelmente representa a maior contribuição para a diversidade regional da herpetofauna no baixo rio Purus (diversidade Gama-γ).

The lower Purus River Basin, Central Amazonia - Brazil, represents an area of prominent interest for conservation of amphibians and reptiles. However, there is little available information about these groups for flooded and nonflooded forests, the major landscapes in this region. We sampled a representative area over two periods: 2004-2005 and 2009-2010. We used efficient and complementary techniques for sampling the herpetofauna in rainforests: time constrained audio-visual search (TAVS), pitfall traps with drift fence (PFDF) and double-ended funnel traps with drift fence (FTDF). We recorded a total of 160 species, including 75 amphibians (73 frogs and two caecilians) and 85 reptiles (34 lizards and 51 snakes). The occurrence of the anuran Dendropsophus allenorum represents the first record for Brazil. Comparing the efficiency of the sampling methods, the TAVS was the best method in sampling efficiency for the majority of the herpetofauna species; followed by the PFDF, efficient in sampling terrestrial frogs and litter lizards in the nonflooded forests. We did not use the PFDF in the flooded forests because the soil was water saturated. Despite its low efficiency in sampling terrestrial frogs and litter lizards, the FTDF, was efficient in snake capture and easily adaptable to the saturated soil in flooded forests. The greatest richness of species and groups was found in the nonflooded forests. Families of fossorial and litter species were mostly absent from the flooded forests. However, in the flooded forests we found a large number of arboreal frogs (Hylidae) and of larger heliothermic lizards (Teiidae). When we evaluated each sample period separately, we found a similar richness of the herpetofauna between the different types of forest landscapes, with a bias towards higher diversity in the nonflooded forests. In spite of similar species numbers, the nonflooded and flooded forests had different species assemblages. The total amphibian and Squamata reptilian diversity between the nonflooded and flooded forests (beta-β diversity), sites with more widespread landscapes, possibly represents the major contribution to the regional herpetofauna diversity in the lower Purus River Basin (Gama-γ diversity).

Distribution of frogs in riparian areas of an urban forest fragment in Central Amazonia / Distribuição de anuros em áreas ripárias de um fragmento florestal urbano na Amazônia Central

This study aimed to evaluate how environmental variables (width of valley, stream size, forest edge distance, and leaf-litter depth) affect the abundance and richness of species of frog species in riparian areas of an urban forest fragment in Central Amazonia. The study was conducted at the campus of the Universidade Federal do Amazonas, Manaus, Brazil, between May 2008 and April 2009, when three nocturnal and diurnal samples were taken from ten plots. A total of 17 species belonging to seven families were registered. The number of species recorded per plot varied from seven to 14. We detected a relationship between the edge distance and richness: the plots with lower richness were located near the fragment border. The variables had no significant effect on abundance of each species.

O objetivo do presente estudo foi avaliar os efeitos de variáveis ambientais (largura do baixio, tamanho do corpo d'água, profundidade da liteira e distância da borda) sobre a abundância e riqueza de espécies de anuros em áreas ripárias de um fragmento florestal urbano na Amazônia Central. O estudo foi realizado no campus da Universidade Federal do Amazonas, Manaus, Brasil, entre maio de 2008 e abril de 2009, onde três amostragens diurnas e três noturnas foram realizadas em dez parcelas permanentes. Foram encontradas 17 espécies pertencentes a sete famílias. O número de espécies registrado por parcela variou de sete a 14. Foi detectado um efeito significativo da distância da borda sobre a riqueza de espécies, onde um menor número de espécies foi registrado em parcelas localizadas próximas às bordas do fragmento. As variáveis analisadas não apresentaram efeitos sobre a abundância de cada espécie.