| variability in alkaloid profiles in neotropical poison frogs (dendrobatidae): genetic versus environmental determinants. | dendrobatid frogs produce a diverse set of alkaloids, whose profiles appear characteristic of frogs of each species or, in the case of variable species, of each population. in the case of one widespread species, dendrobates auratus, alkaloid profiles in extracts of skin are markedly different in three populations, one from a pacific island, isla taboga, panama, one from central mountains in panama, and the third from the caribbean coast in costa rica. the first contains three major classes of de ... | 1992 | 1523680 |
| [chytridiomycosis in amphibians--first report in europe]. | declining of amphibian populations is a worldwide phenomenon. a cutaneous mycosis as a cause of death in free-living amphibians as well as in captive ones due to an chytrid fungus (batrachochytrium dendrobatidis) was reported at first in 1998. this infections were reported hitherto from australia, north, central and south america. this is the first report on chytrid infections in captive anurans from europe. dendrobates auratus and d. pumilo imported from costa rica and p. vittatus imported from ... | 2000 | 11084755 |
| preparation and ultrastructure of spermatozoa from green poison frogs, dendrobates auratus, following hormonal induced spermiation (amphibia, anura, dendrobatidae). | few ultrastructural studies have been performed on members of the dendrobatidae, although such investigations can be useful for the understanding of reproductive patterns, as a diagnostic method for males in breeding programs for endangered amphibians and for phylogenetic analysis. the sperm ultrastructure of the green poison frog, dendrobates auratus, from panama is described following induced spermiation in living animals. to date only testicular spermatozoa in other dendrobatid frogs have bee ... | 2009 | 18657373 |
| concurrent infection with ranavirus, batrachochytrium dendrobatidis, and aeromonas in a captive anuran colony. | four species (dendrobates auratus, phyllobates terribilis, pyxicephalus adspersus, and rhacophorus dennysi) of captive anurans with a clinical history of lethargy and inappetence were found dead and were submitted for necropsy. gross lesions included irregular patches of sloughed skin and rare dermal ulcerations. histologic findings included epidermal proliferation that was most pronounced on the digits and that included intracytoplasmic chytrid organisms. bacteria were often associated with the ... | 2008 | 18817009 |
| efficacy of treatment and long-term follow-up of batrachochytrium dendrobatidis pcr-positive anurans following itraconazole bath treatment. | all anuran specimens in the wildlife conservation society's collections testing positive for batrachochytrium dendrobatidis (bd) were treated with itraconazole and then studied after treatment to assess the long-term effects of itraconazole and the drug's effectiveness in eliminating bd carriers. twenty-four individuals and eight colonies of 11 different species (75 total specimens) tested positive for bd via polymerase chain reaction (pcr) on multicollection survey. all positive individuals and ... | 2013 | 23805558 |
| hydrocoelom and lymphedema in dendrobatid frogs at national aquarium, baltimore: 2003-2011. | hydrocoelom and lymphedema are common in amphibians. in the family dendrobatidae at the national aquarium, baltimore, prevalence was 3.19% from 2005 to 2011. complete review of all cases in dendrobatids from 01 january 2003 to 01 june 2011 at the national aquarium identified annual incidence rate, associated signs, diagnostic findings, therapeutics, and outcomes using medical record review. associated etiologies were assessed via available necropsy and histopathology reports. hydrocoelom was def ... | 2015 | 25831572 |
| the extraordinary biology and development of marsupial frogs (hemiphractidae) in comparison with fish, mammals, birds, amphibians and other animals. | the study of oogenesis and early development of frogs belonging to the family hemiphractidae provide important comparison to the aquatic development of other frogs, such as xenopus laevis, because reproduction on land characterizes the hemiphractidae. in this review, the multinucleated oogenesis of the marsupial frog flectonotus pygmaeus (hemiphractidae) is analyzed and interpreted. in addition, the adaptations associated with the incubation of embryos in the pouch of the female marsupial frog g ... | 0 | 29305906 |
| analysis of cell size in the gastrula of ten frog species reveals a correlation of egg with cell sizes, and a conserved pattern of small cells in the marginal zone. | we investigated the relationship between egg and cell sizes in the early gastrula of ten species of frogs with eggs of 1,100-3,500 μm diameters. we asked whether differences in cell size of the vegetal region, blastocoel roof, and marginal zone of the early gastrula were associated with egg size. alternatively, we proposed that cell size differences may associate with gastrulation characteristics. the analyzed species were as follows: xenopus laevis, engystomops randi, engystomops coloradorum, e ... | 2017 | 27381278 |
| body size but not warning signal luminance influences predation risk in recently metamorphosed poison frogs. | during early development, many aposematic species have bright and conspicuous warning appearance, but have yet to acquire chemical defenses, a phenotypic state which presumably makes them vulnerable to predation. body size and signal luminance in particular are known to be sensitive to variation in early nutrition. however, the relative importance of these traits as determinants of predation risk in juveniles is not known. to address this question, we utilized computer-assisted design (cad) and ... | 2015 | 26668726 |
| poor alkaloid sequestration by arrow poison frogs of the genus phyllobates from costa rica. | frogs of the genus phyllobates from colombia are known to contain the highly toxic alkaloid batrachotoxin, but species from central america exhibit only very low levels or are entirely free of this toxin. in the present study alcohol extracts from 101 specimens of phyllobates lugubris and phyllobates vittatus and 21 of three sympatric species (dendrobates pumilio, dendrobates auratus, dendrobates granuliferus) from costa rica were analyzed by gas chromatography-mass spectrometry. whereas the ext ... | 2014 | 24467995 |
| burst-swimming performance predicts the outcome of cannibalistic interactions in green poison frog larvae (dendrobates auratus). | whole-animal performance (e.g., swimming speed, bite force) functions as a fundamental link between organism and environment and, as such, performance characteristics are important in determining the outcomes of agonistic interactions, both interspecific and intraspecific. cannibalism is an intraspecific agonistic interaction for which winners may be expected to exhibit superior performance in characteristics relevant to cannibalistic behavior. the larvae of the green poison frog (dendrobates au ... | 2013 | 23922259 |
| evidence for an enantioselective pumiliotoxin 7-hydroxylase in dendrobatid poison frogs of the genus dendrobates. | dendrobatid poison frogs readily accumulate alkaloids from diet into skin, where such compounds serve as a chemical defense against predators. arthropods seem to be the source of decahydroquinolines (dhqs), several izidines, coccinellines, spiropyrrolizidines, pumiliotoxins (ptxs), and allopumiliotoxins (aptxs). a dhq iso-223f, and ptx (+)-251d were fed to poison frogs of the dendrobatid genera dendrobates, epipedobates, and phyllobates. the two alkaloids were accumulated in skin unchanged excep ... | 2003 | 12960405 |
| ultrastructural patterns of secretory activity in poison cutaneous glands of larval and juvenile dendrobates auratus (amphibia, anura). | a transmission electron-microscope study has been performed on larval and juvenile skin of the central american arrow-frog dendrobates auratus to investigate early secretory processes and maturational changes in the serous (poison) glands. poison biosynthesis involves the endoplasmic reticulum (both smooth and rough types), as well as golgi stacks which release early serous product as secretory vesicles (or pre-granules). these vesicles contain fine-grained material, along with single electron-o ... | 2003 | 12467659 |
| dietary source for skin alkaloids of poison frogs (dendrobatidae)? | a wide range of alkaloids, many of which are unknown elsewhere in nature, occur in skin of frogs. major classes of such alkaloids in dendrobatid frogs are the batrachotoxins, pumiliotoxins, histrionicotoxins, gephyrotoxins, and decahydroquinolines. such alkaloids are absent in skin of frogs (dendrobates auratus) raised in panama on wingless fruit flies in indoor terraria. raised on leaf-litter arthropods that were collected in a mainland site, such terraria-raised frogs contain tricyclic alkaloi ... | 1994 | 24242207 |
| [steroids from dendrobates auratus]. | | 1977 | 917123 |
| survey of ranavirus and batrachochytrium dendrobatidis in introduced frogs in hawaii, usa. | ranaviruses and the fungus batrachochytrium dendrobatidis are globally important agents of emerging infectious amphibian diseases. amphibians on oahu, the hawaiian island with the greatest potential for disease introduction through the movement of goods and people, have never been surveyed for ranaviruses or b. dendrobatidis. we surveyed all five species of frogs on oahu, hawaii, us for these pathogens. of 325 individuals sampled from six sites, none were positive for ranavirus. however, we foun ... | 2019 | 30768916 |
| cognitive phenotype and differential gene expression in a hippocampal homologue in two species of frog. | the complexity of an animal's interaction with its physical and/or social environment is thought to be associated with behavioral flexibility and cognitive phenotype, though we know little about this relationship in amphibians. we examined differences in cognitive phenotype in two species of frog with divergent natural histories. the green-and-black poison frog (dendrobates auratus) is diurnal, displays enduring social interactions, and uses spatially distributed resources during parental care. ... | 2020 | 32413121 |
| a cognitive map in a poison frog. | a fundamental question in cognitive science is whether an animal can use a cognitive map. a cognitive map is a mental representation of the external world, and knowledge of one's place in this world, that can be used to determine efficient routes to any destination. many birds and mammals are known to employ a cognitive map, but whether other vertebrates can create a cognitive map is less clear. amphibians are capable of using beacons, gradients and landmarks when navigating, and many are profic ... | 2019 | 31182504 |
| variation in pigmentation gene expression is associated with distinct aposematic color morphs in the poison frog dendrobates auratus. | color and pattern phenotypes have clear implications for survival and reproduction in many species. however, the mechanisms that produce this coloration are still poorly characterized, especially at the genomic level. here we have taken a transcriptomics-based approach to elucidate the underlying genetic mechanisms affecting color and pattern in a highly polytypic poison frog. we sequenced rna from the skin from four different color morphs during the final stage of metamorphosis and assembled a ... | 2019 | 30995908 |
| environmental and host effects on skin bacterial community composition in panamanian frogs. | research on the amphibian skin microbiota has focused on identifying bacterial taxa that deter a pathogenic chytrid fungus, and on describing patterns of microbiota variation. however, it remains unclear how environmental variation affects amphibian skin bacterial communities, and whether the overall functional diversity of the amphibian skin microbiota is associated to such variation. we sampled skin microbial communities from one dendrobatoid frog species across an environmental gradient along ... | 2018 | 29520260 |