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1.
Animals (Basel) ; 14(10)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38791625

RESUMO

Phenotypic traits can evolve independently at different stages of ontogeny, optimizing adaptation to distinct ecological contexts and increasing morphological diversity in species with complex life cycles. Given the relative independence resulting from the profound changes induced by metamorphosis, niche occupation and resource utilization in tadpoles may prompt evolutionary responses that do not necessarily affect the adults. Consequently, diversity patterns observed in the larval shape may not necessarily correspond to those found in the adult shape for the same species, a premise that can be tested through the Adaptive Decoupling Hypothesis (ADH). Herein, we investigate the ADH for larval and adult shape differentiation in Neoaustrarana frogs. Neoaustrarana frogs, particularly within the Cycloramphidae family, exhibit remarkable diversity in tadpole morphology, making them an ideal model for studying adaptive decoupling. By analyzing 83 representative species across four families (Alsodidae, Batrachylidae, Cycloramphidae, and Hylodidae), we generate a morphological dataset for both larval and adult forms. We found a low correlation between larval and adult shapes, species with a highly distinct larval shape having relatively similar shape when adults. Larval morphological disparity is not a good predictor for adult morphological disparity within the group, with distinct patterns observed among families. Differences between families are notable in other aspects as well, such as the role of allometric components influencing shape and morphospace occupancy. The larval shape has higher phylogenetic structure than the adult. Evolutionary convergence emerges as a mechanism of diversification for both larval and adult shapes in the early evolution of neoaustraranans, with shape disparity of tadpoles reaching stable levels since the Oligocene. The widest occupation in morphospace involves families associated with dynamically changing environments over geological time. Our findings support the ADH driving phenotypic diversity in Neoaustrarana, underscoring the importance of considering ontogenetic stages in evolutionary studies.

2.
PeerJ ; 12: e17232, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646479

RESUMO

The species richness in the Neotropics has been linked to environmental heterogeneity and a complex geological history. We evaluated which biogeographic processes were associated with the diversification of Monkey tree frogs, an endemic clade from the Neotropics. We tested two competing hypotheses: the diversification of Phyllomedusinae occurred either in a "south-north" or a "north-south" direction in the Neotropics. We also hypothesized that marine introgressions and Andean uplift had a crucial role in promoting their diversification. We used 13 molecular markers in a Bayesian analysis to infer phylogenetic relationships among 57 species of Phyllomedusinae and to estimate their divergence times. We estimated ancestral ranges based on 12 biogeographic units considering the landscape modifications of the Neotropical region. We found that the Phyllomedusinae hypothetical ancestor range was probably widespread throughout South America, from Western Amazon to Southern Atlantic Forest, at 29.5 Mya. The Phyllomedusines' ancestor must have initially diverged through vicariance, generally followed by jump-dispersals and sympatric speciation. Dispersal among areas occurred mostly from Western Amazonia towards Northern Andes and the South American diagonal of dry landscapes, a divergent pattern from both "south-north" and "north-south" diversification hypotheses. Our results revealed a complex diversification process of Monkey tree frogs, occurring simultaneously with the orogeny of Northern Andes and the South American marine introgressions in the last 30 million years.


Assuntos
Anuros , Teorema de Bayes , Filogenia , Animais , Anuros/genética , Anuros/classificação , América do Sul , Filogeografia , Especiação Genética
3.
Environ Sci Pollut Res Int ; 31(49): 59457-59471, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39354261

RESUMO

Chemical pollutants include the harmful effects of various substances on soils, water bodies, and biodiversity. Amphibians are one of the most endangered groups of vertebrates and are impacted by chemical pollutants in various ways due to their complex life cycles. Since trace pollutant concentrations vary across environments, different frog ecomorphs (classified by their microhabitat use) may have different exposures. We aimed to determine the association between frog ecomorphs and the occurrence of histopathological hepatic lesions (HHLs) as an indicator of contaminant exposure. We focused on small forest streams near a large urban region in Brazil, heavily polluted in the 1980s. We examined 104 frog specimens from various families. All specimens exhibited HHLs, with melanomacrophages being the most common (n = 99). Arboreal frogs exhibited more vascular congestion, while terrestrial frogs showed structural hepatic damage. Higher cobalt levels were linked to increased liver necrosis in arboreal frogs and structural issues in both arboreal and terrestrial frogs. Cadmium was associated with hepatitis in terrestrial frogs. Although metal levels had no significant effects on rheophilic frogs, the prevalence of hepatitis and necrosis indicated complex exposure pathways. Iron and aluminum were linked to fewer lesions in rheophilic frogs, suggesting resilience. The high prevalence of HHLs signals an ongoing issue, with variations among ecomorphs suggesting differential exposure to pollutants and posing a complex challenge for community conservation.


Assuntos
Anuros , Monitoramento Ambiental , Fígado , Animais , Brasil , Fígado/efeitos dos fármacos , Metais/toxicidade , Poluentes Químicos da Água/toxicidade
4.
Zootaxa ; 5254(2): 287-294, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-37044721

RESUMO

Cycloramphus Tschudi is the most speciose genus in the family Cycloramphidae, including 30 species endemic to the Atlantic forest Domain in Brazil (Frost 2022). Species in the genus may be classified as saxicolous and terrestrial based on morphology and reproductive mode. Saxicolous are flat-bodied species, with granular skin, and interdigital web (Heyer 1983a), associated with fast-flowing streams in all life history phases. They lay eggs over humid rocks, logs, or crevices in the splash zone, from which semiterrestrial tadpoles hatch (McDiarmid & Altig 1999; Dias et al. 2021) that feed over humid rocks inside the stream or dripping rocky walls (Lutz 1929; Heyer 1983a, b; Haddad & Sazima 1989; Giaretta & Cardoso 1995; Giaretta & Facure 2003; Lima et al. 2010). The single exception to this pattern is C. bandeirensis Heyer 1983a, which share the morphology of adults and larvae, but lives terrestrially, away from streams, in the rocky fields of open high elevation grasslands of Caparaó National Park (Verdade et al. 2019).


Assuntos
Anuros , Ranidae , Animais , Larva , Florestas
5.
Zootaxa ; 5068(4): 517-532, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34810693

RESUMO

We describe a new species of dull-colored flea-toad, genus Brachycephalus, from the Atlantic Forest of Capara mountains in southeastern Brazil. The new species is characterized by its diminutive size, leptodactyliform body, brownish color with an inverted V-shaped dark mark on dorsum, skin smooth, hyperossification and dorsal shield absent, linea masculinea absent, Fingers I and IV vestigial, Toe I externally absent, Toe II reduced but functional, Toes III and IV with pointed tips, Toe V vestigial, and ventral color uniformly brown. It is a leaf litter dweller, known only from type locality in the humid forests on the eastern slopes of Parque Nacional do Capara mountains, a protected area in the states of Esprito Santo and Minas Gerais, southeastern Brazil. It is the third flea-toad occurring in the state of Esprito Santo recovered as sister to all other Brachycephalus distributed from the state of So Paulo northward in the Atlantic Forest.


Assuntos
Anuros , Sifonápteros , Animais , Brasil , Bufonidae , Florestas
6.
Zootaxa ; 4668(1): zootaxa.4668.1.11, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31716646

RESUMO

The genus Zachaenus Cope is the least specious within Cycloramphidae, including two species: Z. carvalhoi Izecksohn, and Z. parvulus (Girard). Both are leaf litter species distributed across Atlantic forest remnants in Southeastern Brazil. Zachaenus carvalhoi occurs westerly in the states of Espírito Santo and Minas Gerais, and Z. parvulus easterly in the states of São Paulo, Rio de Janeiro, and Espírito Santo (Verdade et al. 2009; Motta et al. 2010; Salles Maciel 2010; Oliveira et al. 2012; Guedes et al. 2019; Frost 2019). Both species build terrestrial nests, and larval development is endotrophic nidicolous (reproductive mode 21 after Haddad Prado 2005; Lutz 1944; Thibaudeau Altig 1999; Zocca et al. 2014). In this work, we describe the tadpoles of Z. carvalhoi, and discuss morphological aspects regarding other endotrophic tadpoles.


Assuntos
Ranidae , Animais , Brasil , Florestas , Larva
7.
J Cosmet Sci ; 58(1): 45-51, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17342267

RESUMO

Clay facial masks--formulations that contain a high percentage of solids dispersed in a liquid vehicle--have become of special interest due to specific properties presented by clays, such as particle size, cooling index, high adsorption capacity, and plasticity. Although most of the physicochemical properties of clay dispersions have been studied, specific aspects concerning the physicochemical stability of clay mask products remain unclear. This work aimed at investigating the accelerated physicochemical stability of clay mask formulations stored at different temperatures. Formulations were subjected to centrifuge testing and to thermal treatment for 15 days, during which temperature was varied from -5.0 degrees to 45.0 degrees C. The apparent viscosity and visual aspect (homogeneity) of all formulations were affected by temperature variation, whereas color, odor, and pH value remained unaltered. These results, besides the estimation of physicochemical stability under aging, can be useful in determining the best storage conditions for clay-based formulations.


Assuntos
Silicatos de Alumínio/química , Cosméticos/química , Argila , Cor , Concentração de Íons de Hidrogênio , Higiene da Pele/métodos , Temperatura , Viscosidade
8.
Zootaxa ; 4179(1): 139-143, 2016 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-27811700

RESUMO

Hypsiboas guentheri is a species of treefrog that inhabits the surrounding vegetation of temporary and permanent ponds at the coastal region of Southern Brazil, in the States of Santa Catarina and Rio Grande do Sul (Langone 1997; Frost 2016). It belongs to the H. pulchellus species group (Faivovich et al. 2004, Duellman et al. 2016), this group contains 39 species (Frost 2016), but formal descriptions of tadpoles are missing for 15 of them (Kolenc et al. 2008; Pinheiro et al., 2016). Herein we describe tadpoles of H. guentheri collected in February 2014 in the accumulated water on an underpass for wildlife crossing at the RS-486 highway (29º30'44.8" S 50º06'29.9" W), Itati municipality, Rio Grande do Sul State, Brazil.


Assuntos
Anuros/crescimento & desenvolvimento , Animais , Brasil , Larva/anatomia & histologia , Especificidade da Espécie
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