| gastrulation of gastrotheca riobambae in comparison with other frogs. | blastopore formation, the embryonic disk, archenteron and notochord elongation, and brachyury expression in the marsupial frog gastrotheca riobambae was compared with embryos of xenopus laevis and of the dendrobatids colostethus machalilla and epipedobates anthonyi. in contrast with x. laevis embryos, the blastopore closes before elongation of the archenteron and notochord in the embryos of g. riobambae and of the dendrobatid frogs. moreover, the circumblastoporal collar (cbc) thickens due to th ... | 2007 | 17306246 |
| 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 |
| contact toxicities of anuran skin alkaloids against the fire ant (solenopsis invicta). | nearly 500 alkaloids, representing over 20 structural classes, have been identified from the skin of neotropical poison frogs (dendrobatidae). these cutaneous compounds, which are derived from arthropod prey of the frogs, generally are believed to deter predators. we tested the red imported fire ant (solenopsis invicta) for toxicosis following contact with 20 alkaloids (12 structural classes) identified from dendrobatids or other anurans. individual ants forced to contact the dried residues of 1 ... | 2013 | 23340579 |
| phantasmidine: an epibatidine congener from the ecuadorian poison frog epipedobates anthonyi. | the skin of the ecuadorian poison frog epipedobates anthonyi contains the potent nicotinic agonists epibatidine (1) and n-methylepibatidine (3). in addition, a condensed tetracyclic epibatidine congener has been identified with activity at nicotinic acetylcholine receptors, but different selectivity than epibatidine. this rigid tetracycle has been named phantasmidine (4). phantasmidine has a molecular formula of c(11)h(11)n(2)ocl, shares a chloropyridine moiety with 1, and also contains furan, p ... | 2010 | 20337496 |
| isolation and characterization of 12 microsatellite loci in epipedobates anthonyi (amphibia: anura: dendrobatidae) for population genetic analysis. | tropical anurans are among the most diverse and vulnerable organisms on earth, yet the evolutionary mechanisms behind their diversity remain relatively unexplored. epipedobates anthonyi is a poison frog that inhabits southern ecuador and northern peru along a broad elevational range (0-1800 m). throughout its range, this species exhibits variation in phenotypic traits, such as color, advertisement calls, and alkaloid composition. the aim of this study is to isolate and characterize microsatellit ... | 2019 | 30929161 |
| absolute configuration and pharmacology of the poison frog alkaloid phantasmidine. | phantasmidine, a rigid congener of the well-known nicotinic acetylcholine receptor agonist epibatidine, is found in the same species of poison frog ( epipedobates anthonyi). natural phantasmidine was found to be a 4:1 scalemic mixture, enriched in the (2a r,4a s,9a s) enantiomer by chiral-phase lc-ms comparison to the synthetic enantiomers whose absolute configurations were previously established by mosher's amide analysis. the major enantiomer has the opposite s configuration at the benzylic ca ... | 2018 | 29671588 |