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2.
Science ; 377(6612): 1272, 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-36108017
3.
Zootaxa ; 5134(2): 151-196, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36101070

RESUMO

John Edwards Holbrook published North American Herpetology in 11 volumes from 18361842, authoring the first accounts of numerous amphibians and reptiles from the eastern and central United States, including 32 salamanders (Urodela). We reviewed these and located 51 extant salamander specimens from Holbrook in the Academy of Natural Sciences (Philadelphia), Museum of Comparative Zoology (Cambridge), and Musum national dHistoire naturelle (Paris), six of which are types. We identified four other specimens figured by Holbrook in the MNHN and National Museum of Natural History (Washington), all of which are types from descriptions by other authors. We designate lectotypes for S. porpyhritica Green, 1827 (USNM 3840; reversing neotype MCZ A-35778), Salamandra gutto-lineata Holbrook, 1838a (ANSP 716), S. auriculata Holbrook, 1838b (MNHN-RA 0.4675), S. maculo-quadrata Holbrook, 1840 (ANSP 821), S. granulata De Kay in Holbrook, 1842e (USNM 3981), S. quadridigitata Holbrook, 1842e (ANSP 490; reversing neotype UF 178833), and Plethodon variolosum Dumril, Bibron, and Dumril, 1854 (MNHN-RA 0.4666). Allocation of S. auriculata Holbrook, 1838b, S. Haldemani Holbrook, 1840, and P. variolosum Dumril, Bibron, and Dumril, 1854 is still ambiguous. We consider S. maculo-quadrata Holbrook, 1840 to be a junior subjective synonym of S. fusca Green, 1818; no valid name has ever been applied to Black-bellied Salamanders (Desmognathus sp. quadramaculatus) at the species level, and up to five candidate species require new names. Additional discoveries of data and specimens pertaining to Holbrooks names may remain to be made among his surviving papers and collections.


Assuntos
Anfíbios , Urodelos , Animais , Museus
4.
Zootaxa ; 5168(2): 207-221, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-36101289

RESUMO

Previous phylogenetic studies based on mitochondrial DNA data have consistently suggested that Hynobius tokyoensis consists of two major clades, clade A (northern clade) and clade B (southern clade). In this study, we newly estimated their population genetic structure and phylogenetic relationships by nuclear SNPs, and the results suggested heterospecific relationships of the two mitochondrial clades, without present hybridization in between. They were also recognized as morphologically different. The type locality of H. tokyoensis is in Tokyo Prefecture, and therefore clade B corresponds to H. tokyoensis sensu stricto, leaving clade A without available scientific name. We, thus, describe the clade A from northeastern Kanto to southern Tohoku as a new species Hynobius sengokui. The new species is distinguished from H. tokyoensis by its relatively longer axilla-groin distance, shorter trunk, and deeper vomerine teeth series, and is estimated to have diverged from it during the late Pliocene.


Assuntos
Anfíbios , Urodelos , Animais , DNA Mitocondrial/genética , Japão , Filogenia
5.
Vet Clin North Am Exot Anim Pract ; 25(3): 585-596, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36122941

RESUMO

Monitoring blood lactate concentrations with a handheld, point-of-care (POC) meter is an efficient and inexpensive method of monitoring critically ill or anesthetized exotic patients. Serial monitoring of lactate allows early recognition of hypoperfusion, allowing for prompt implementation of resuscitative efforts. Reference ranges for exotic animals are currently sparse and often gathered from field studies of wild animals. In the absence of reference ranges, extrapolations can be made regarding mammals and birds, but may be more difficult in reptiles and amphibians.


Assuntos
Animais Exóticos , Ácido Láctico , Anfíbios , Animais , Mamíferos , Sistemas Automatizados de Assistência Junto ao Leito , Répteis
6.
Sci Rep ; 12(1): 14839, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36050350

RESUMO

Understanding the geographic distribution of species is crucial for establishing protected areas. This study aimed to identify the preferred habitat environment of South Korean herpetofauna using distribution point information, providing the information necessary to protect their habitat by establishing a species distribution model. We found that climate variables in the region where 19 amphibians and 20 reptiles were distributed correlated with the altitude, suggesting that altitude had a major influence on their distribution. The species distribution modeling indicated that 10-12 amphibian and 13-16 reptile species inhabit the Gangwon-do region, forming hotspot areas in the eastern and western regions around the Taebaek Mountains. Some of these hotspot areas occurred in the Demilitarized Zone and national parks, which are government-managed ecological conservation areas. However, some hotspot areas are vulnerable to habitat destruction due to development and deforestation as they are not designated conservation areas. Therefore, it is necessary to establish new conservation areas with a focus on herpetofauna after confirming the actual inhabitation of species through precise monitoring in predicted hotspot areas and designating them as protected areas. Our results can serve as important basic data for establishing protection measures and designating protected areas for herpetofauna species.


Assuntos
Anfíbios , Répteis , Animais , Biodiversidade , Clima , Conservação dos Recursos Naturais/métodos , Ecossistema , República da Coreia
7.
Can J Microbiol ; 68(9): 583-593, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35979959

RESUMO

Temporal changes and transmission patterns in host-associated microbial communities have important implications for host health. The diversity of amphibian skin microbial communities is associated with disease outcome in amphibians exposed to the fungal pathogen Batrachochytrium dendrobatidis (Bd). To successfully develop conservation strategies against Bd, we need a comprehensive understanding of how skin microbes are maintained and transmitted over time within populations. We used 16S rRNA sequence analysis to compare Epipedobates anthonyi frogs housed with one conspecific to frogs housed singly at four time points over the course of 1 year. We found that both α and ß diversity of frog skin bacterial communities changed significantly over the course of the experiment. Specifically, we found that bacterial communities of cohabitating frogs became more similar over time. We also observed that some bacterial taxa were differentially abundant between frogs housed singly and frogs housed with a conspecific. These results suggest that conspecific contact may play a role in mediating amphibian skin microbial diversity and that turnover of skin microbial communities can occur across time. Our findings provide rationale for future studies exploring horizontal transmission as a potential mechanism of host-associated microbial maintenance in amphibians.


Assuntos
Quitridiomicetos , Microbiota , Anfíbios/genética , Anfíbios/microbiologia , Animais , Bactérias/genética , Quitridiomicetos/genética , RNA Ribossômico 16S/genética , Pele/microbiologia
8.
Dev Comp Immunol ; 136: 104510, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35985564

RESUMO

Amphibians are among the vertebrate groups suffering great losses of biodiversity due to a variety of causes including diseases, such as chytridiomycosis (caused by the fungal pathogens Batrachochytrium dendrobatidis and B. salamandrivorans). The amphibian metamorphic period has been identified as being particularly vulnerable to chytridiomycosis, with dramatic physiological and immunological reorganisation likely contributing to this vulnerability. Here, we overview the processes behind these changes at metamorphosis and then perform a systematic literature review to capture the breadth of empirical research performed over the last two decades on the metamorphic immune response. We found that few studies focused specifically on the immune response during the peri-metamorphic stages of amphibian development and fewer still on the implications of their findings with respect to chytridiomycosis. We recommend future studies consider components of the immune system that are currently under-represented in the literature on amphibian metamorphosis, particularly pathogen recognition pathways. Although logistically challenging, we suggest varying the timing of exposure to Bd across metamorphosis to examine the relative importance of pathogen evasion, suppression or dysregulation of the immune system. We also suggest elucidating the underlying mechanisms of the increased susceptibility to chytridiomycosis at metamorphosis and the associated implications for population persistence. For species that overlap a distribution where Bd/Bsal are now endemic, we recommend a greater focus on management strategies that consider the important peri-metamorphic period.


Assuntos
Quitridiomicetos , Micoses , Anfíbios , Animais , Quitridiomicetos/fisiologia , Sistema Imunitário , Metamorfose Biológica
9.
World J Pediatr ; 18(10): 643-646, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35939203

Assuntos
Anfíbios , Animais , Humanos
10.
Sci Rep ; 12(1): 13634, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35948609

RESUMO

The epidermal differentiation complex (EDC) is a cluster of genes encoding components of the skin barrier in terrestrial vertebrates. EDC genes can be categorized as S100 fused-type protein (SFTP) genes such as filaggrin, which contain two coding exons, and single-coding-exon EDC (SEDC) genes such as loricrin. SFTPs are known to be present in amniotes (mammals, reptiles and birds) and amphibians, whereas SEDCs have not yet been reported in amphibians. Here, we show that caecilians (Amphibia: Gymnophiona) have both SFTP and SEDC genes. Two to four SEDC genes were identified in the genomes of Rhinatrema bivittatum, Microcaecilia unicolor and Geotrypetes seraphini. Comparative analysis of tissue transcriptomes indicated predominant expression of SEDC genes in the skin of caecilians. The proteins encoded by caecilian SEDC genes resemble human SEDC proteins, such as involucrin and small proline-rich proteins, with regard to low sequence complexity and high contents of proline, glutamine and lysine. Our data reveal diversification of EDC genes in amphibians and suggest that SEDC-type skin barrier genes have originated either in a common ancestor of tetrapods followed by loss in Batrachia (frogs and salamanders) or, by convergent evolution, in caecilians and amniotes.


Assuntos
Anfíbios , Répteis , Anfíbios/genética , Animais , Epiderme , Humanos , Mamíferos , Filogenia , Prolina/genética , Répteis/genética , Proteínas S100/genética
11.
Commun Biol ; 5(1): 679, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927327

RESUMO

The IUCN Red List of Threatened Species is essential for practical and theoretical efforts to protect biodiversity. However, species classified as "Data Deficient" (DD) regularly mislead practitioners due to their uncertain extinction risk. Here we present machine learning-derived probabilities of being threatened by extinction for 7699 DD species, comprising 17% of the entire IUCN spatial datasets. Our predictions suggest that DD species as a group may in fact be more threatened than data-sufficient species. We found that 85% of DD amphibians are likely to be threatened by extinction, as well as more than half of DD species in many other taxonomic groups, such as mammals and reptiles. Consequently, our predictions indicate that, amongst others, the conservation relevance of biodiversity hotspots in South America may be boosted by up to 20% if DD species were acknowledged. The predicted probabilities for DD species are highly variable across taxa and regions, implying current Red List-derived indices and priorities may be biased.


Assuntos
Conservação dos Recursos Naturais , Extinção Biológica , Anfíbios , Animais , Biodiversidade , Espécies em Perigo de Extinção , Mamíferos
13.
Proc Biol Sci ; 289(1981): 20220841, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35975445

RESUMO

Developmental pathways encompass transcription factors and cis-regulatory elements that interact as transcription factor-regulatory element (TF-RE) units. Independent origins of similar phenotypes likely involve changes in different parts of these units, a hypothesis promisingly tested addressing the evolution of the rib-associated lumbar (RAL) morphotype that characterizes emblematic animals such as snakes and elephants. Previous investigation in these lineages identified a polymorphism in the Homology region 1 [H1] enhancer of the Myogenic factor-5 [Myf5], which interacts with HOX10 proteins to modulate rib development. Here we address the evolution of TF-RE units focusing on independent origins of RAL morphotypes. We compiled an extensive database for H1-Myf5 and HOX10 sequences with two goals: (i) evaluate if the enhancer polymorphism is present in amphibians exhibiting the RAL morphotype and (ii) test a hypothesis of enhanced evolutionary flexibility mediated by TF-RE units, according to which independent origins of the RAL morphotype might involve changes in either component of the interaction unit. We identified the H1-Myf5 polymorphism in lineages that diverged around 340 Ma, including Lissamphibia. Independent origins of the RAL morphotype in Tetrapoda involved sequence variation in either component of the TF-RE unit, confirming that different changes may similarly affect the phenotypic outcome of a given developmental pathway.


Assuntos
Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição , Anfíbios/metabolismo , Animais , Fator Regulador Miogênico 5/genética , Fator Regulador Miogênico 5/metabolismo , Serpentes/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
Environ Pollut ; 310: 119823, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35931387

RESUMO

Glyphosate-based herbicides are used worldwide, and glyphosate's primary metabolite (aminomethylphosphonic acid: AMPA), is globally retrieved in surface waters. AMPA induces various adverse effects on aquatic wildlife, including selective mortality, which suggests that glyphosate exposure may have selected for AMPA-resistant individuals. We tested this hypothesis using spined toads (Bufo spinosus), an amphibian found in a variety of habitats, from AMPA-exposed agricultural lands to AMPA-free forested areas. We predicted that the offspring of individuals originating from agricultural habitats would develop AMPA-resistance - and be less prone to develop adverse effects from- AMPA exposure. To investigate this question, we performed a common garden brood-rearing experiment. The embryos and larvae of 40 spined toad pairs captured in agricultural and forest ponds were exposed either to an environmental relevant concentration of AMPA (0.4 µg L-1) or to control conditions (n = 8160 embryos, n = 240 tadpoles). We monitored development durations, developmental abnormalities and morphology, measured across key developmental stages. Although we observed significant effects of AMPA on fitness parameters in each group, these effects were not exacerbated in individuals from AMPA-free habitats. We suggest that temporal and/or spatial dynamics of contamination, as well as gene flow between exposed and preserved populations, may hinder adaptive divergence between populations. Yet, we show strong adverse effects of AMPA exposure at early developmental stages. AMPA could therefore be one of the numerous causes of declining wild amphibian populations.


Assuntos
Glicina , Herbicidas , Anfíbios , Animais , Ecossistema , Glicina/análogos & derivados , Humanos , Larva
15.
Biological sciences ; 289(1981)Aug. 2022.
Artigo em Inglês | Sec. Est. Saúde SP, CONASS, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1393200

RESUMO

ABSTRACT: Developmental pathways encompass transcription factors and cis-regulatory elements that interact as transcription factor-regulatory element (TF-RE) units. Independent origins of similar phenotypes likely involve changes in different parts of these units, a hypothesis promisingly tested addressing the evolution of the rib-associated lumbar (RAL) morphotype that characterizes emblematic animals such as snakes and elephants. Previous investigation in these lineages identified a polymorphism in the Homology region 1 [H1] enhancer of the Myogenic factor-5 [Myf5], which interacts with HOX10 proteins to modulate rib development. Here we address the evolution of TF-RE units focusing on independent origins of RAL morphotypes. We compiled an extensive database for H1-Myf5 and HOX10 sequences with two goals: (i) evaluate if the enhancer polymorphism is present in amphibians exhibiting the RAL morphotype and (ii) test a hypothesis of enhanced evolutionary flexibility mediated by TF-RE units, according to which independent origins of the RAL morphotype might involve changes in either component of the interaction unit. We identified the H1-Myf5 polymorphism in lineages that diverged around 340 Ma, including Lissamphibia. Independent origins of the RAL morphotype in Tetrapoda involved sequence variation in either component of the TF-RE unit, confirming that different changes may similarly affect the phenotypic outcome of a given developmental pathway.


Assuntos
Animais , Serpentes/genética , Sequências Reguladoras de Ácido Nucleico , Fator Regulador Miogênico 5/genética , Fator Regulador Miogênico 5/metabolismo , Anfíbios/metabolismo
16.
Mol Ecol ; 31(17): 4558-4570, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35796691

RESUMO

While some pathogens are limited to single species, others can colonize many hosts, likely contributing to the emergence of novel disease outbreaks. Despite this biodiversity threat, traits associated with host niche expansions are not well understood in multihost pathogens. Here, we aimed to uncover functional machinery driving multihost invasion by focusing on Batrachochytrium dendrobatidis (Bd), a pathogen that infects the skin of hundreds of amphibians worldwide. We performed a meta-analysis of Bd gene expression using data from published infection experiments and newly generated profiles. We analysed Bd transcriptomic landscapes across the skin of 14 host species, reconstructed Bd isolates phylogenetic relationships, and inferred the origin and evolutionary history of differentially expressed genes under a phylogenetic framework comprising other 12 zoosporic fungi. Bd displayed plastic infection strategies when challenged by hosts with different disease susceptibility. Our analyses identified sets of differentially expressed genes under host environments with similar infection outcome. We stressed nutritional immunity and gene silencing as important processes required to overcome challenging skin environments in less susceptible hosts. Overall, Bd genes expressed during amphibian skin exploitation have arisen mainly via gene duplications with great family expansions, increasing the gene copy events previously described for this fungal species. Finally, we provide a comprehensive gene data set that can be used to further examine eco-evolutionary hypotheses for this host-pathogen system. Our study supports the idea that host environments exert contrasting selective pressures, such that gene expression plasticity could be one of the evolutionary keys leading to the success of multihost pathogens.


Assuntos
Quitridiomicetos , Micoses , Anfíbios/genética , Anfíbios/microbiologia , Animais , Batrachochytrium , Quitridiomicetos/genética , Micoses/genética , Micoses/microbiologia , Micoses/veterinária , Filogenia , Plásticos
17.
Sci Rep ; 12(1): 10829, 2022 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-35902706

RESUMO

Biological invasions by amphibian and reptile species (i.e. herpetofauna) are numerous and widespread, having caused severe impacts on ecosystems, the economy and human health. However, there remains no synthesised assessment of the economic costs of these invasions. Therefore, using the most comprehensive database on the economic costs of invasive alien species worldwide (InvaCost), we analyse the costs caused by invasive alien herpetofauna according to taxonomic, geographic, sectoral and temporal dimensions, as well as the types of these costs. The cost of invasive herpetofauna totaled at 17.0 billion US$ between 1986 and 2020, divided split into 6.3 billion US$ for amphibians, 10.4 billion US$ for reptiles and 334 million US$ for mixed classes. However, these costs were associated predominantly with only two species (brown tree snake Boiga irregularis and American bullfrog Lithobates catesbeianus), with 10.3 and 6.0 billion US$ in costs, respectively. Costs for the remaining 19 reported species were relatively minor (< 0.6 billion US$), and they were entirely unavailable for over 94% of known invasive herpetofauna worldwide. Also, costs were positively correlated with research effort, suggesting research biases towards well-known taxa. So far, costs have been dominated by predictions and extrapolations (79%), and thus empirical observations for impact were relatively scarce. The activity sector most affected by amphibians was authorities-stakeholders through management (> 99%), while for reptiles, impacts were reported mostly through damages to mixed sectors (65%). Geographically, Oceania and Pacific Islands recorded 63% of total costs, followed by Europe (35%) and North America (2%). Cost reports have generally increased over time but peaked between 2011 and 2015 for amphibians and 2006 to 2010 for reptiles. A greater effort in studying the costs of invasive herpetofauna is necessary for a more complete understanding of invasion impacts of these species. We emphasise the need for greater control and prevention policies concerning the spread of current and future invasive herpetofauna.


Assuntos
Anfíbios , Ecossistema , Répteis , Animais , Humanos , Espécies Introduzidas , América do Norte
18.
J Exp Biol ; 225(15)2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35818822

RESUMO

Total resistance (rt) to evaporative water loss (EWL) in amphibians is given by the sum of the boundary layer (rb) and the skin resistance (rs). Thus, rs can be determined if the rb component is defined (rs=rt-rb). The use of agar models has become the standard technique to estimate rb under the assumption that the agar surface imposes no barrier to evaporation (rs=0). We evaluated this assumption by determining EWL rates and rb values from exposed surfaces of free water, a physiological solution mimicking the osmotic properties of a generalized amphibian, and agar gels prepared at various concentrations using either water or physiological solution as diluent. Water evaporation was affected by both the presence of solutes and agar concentration. Models prepared with agar at 5% concentration in water provided the most practical and appropriate proxy for the estimation of rb.


Assuntos
Anfíbios , Água , Ágar , Animais , Perda Insensível de Água/fisiologia
19.
Parasitol Int ; 91: 102617, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35777656

RESUMO

Tongue worms (Subclass: Pentastomida) are endoparasites found in carnivorous reptiles, fish, amphibians, birds, and mammals. Several pentastomids cause pentastomiasis, a zoonotic disease. We encountered tongue worm infection in two reptiles imported into Japan: a Wahlberg's velvet gecko (Homopholis wahlbergii) bred in Germany and a wild-caught green tree python (Morelia viridis) from the Republic of Indonesia. The infecting tongue worms were identified as Raillietiella sp. and Armillifer sp. in the gecko and python, respectively, based on morphological and molecular analyses. Gecko is a newly recorded definitive host harboring Raillietiella tongue worm. Live tongue worms were first detected in domestic reptiles in Japan, and this indicates a risk that these tongue worms could be spread to other animals, as well as humans. Therefore, the diagnosis and treatment of infected pets are of importance. In the case of the two infected reptiles, the availability of fecal egg examination for diagnosis was shown. In addition, the effectiveness of treatment with 200 µg/kg/day ivermectin orally once weekly was demonstrated, without no side-effects and no re-detection of eggs after the cessation of treatment.


Assuntos
Boidae , Lagartos , Pentastomídeos , Anfíbios , Animais , Humanos , Mamíferos , Zoonoses/tratamento farmacológico , Zoonoses/parasitologia
20.
Int J Mol Sci ; 23(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35806198

RESUMO

Herpes simplex virus type-1 (HSV-1) and John Cunningham polyomavirus (JCPyV) are widely distributed DNA viruses causing mainly asymptomatic infection, but also mild to very severe diseases, especially when these viruses reach the brain. Some drugs have been developed to inhibit HSV-1 replication in host cells, but their prolonged use may induce resistance phenomena. In contrast, to date, there is no cure for JCPyV. The search for alternative drugs that can reduce viral infections without undermining the host cell is moving toward antimicrobial peptides (AMPs) of natural occurrence. These include amphibian AMPs belonging to the temporin family. Herein, we focus on temporin G (TG), showing that it strongly affects HSV-1 replication by acting either during the earliest stages of its life cycle or directly on the virion. Computational studies have revealed the ability of TG to interact with HSV-1 glycoprotein B. We also found that TG reduced JCPyV infection, probably affecting both the earliest phases of its life cycle and the viral particle, likely through an interaction with the viral capsid protein VP1. Overall, our results are promising for the development of short naturally occurring peptides as antiviral agents used to counteract diseases related to HSV-1 and JCPyV.


Assuntos
Herpesvirus Humano 1 , Anfíbios , Animais , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos , Herpesvirus Humano 1/fisiologia , Replicação Viral
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