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Ocellatins are peptides produced in the skins of frogs belonging to the genus <i>Leptodactylus</i> that generally display weak antimicrobial activity against Gram-negative bacteria only. Peptidomic analysis of norepinephrine-stimulated skin secretions from <i>Leptodactylus insularum</i> Barbour 1906 and <i>Leptodactylus nesiotus</i> Heyer 1994, collected in the Icacos Peninsula, Trinidad, led to the purification and structural characterization of five ocellatin-related peptides from <i>L. insularum</i> (ocellatin-1I together with its (1–16) fragment, ocellatin-2I and its (1–16) fragment, and ocellatin-3I) and four ocellatins from <i>L. nesiotus</i> (ocellatin-1N, -2N, -3N, and -4N). While ocellatins-1I, -2I, and -1N showed a typically low antimicrobial potency against Gram-negative bacteria, ocellatin-3N (GIFDVLKNLAKGVITSLAS.NH₂) was active against an antibiotic-resistant strain of <i>Klebsiella pneumoniae</i> and reference strains of <i>Escherichia coli</i>, <i>K. pneumoniae</i>, <i>Pseudomonas aeruginosa</i>, and <i>Salmonella typhimurium</i> (minimum inhibitory concentrations (MICs) in the range 31.25–62.5 μM), and was the only peptide active against Gram-positive <i>Staphylococcus aureus</i> (MIC = 31.25 μM) and <i>Enterococcus faecium</i> (MIC = 62.5 μM). The therapeutic potential of ocellatin-3N is limited by its moderate hemolytic activity (LC₅₀ = 98 μM) against mouse erythrocytes. The peptide represents a template for the design of long-acting, non-toxic, and broad-spectrum antimicrobial agents for targeting multidrug-resistant pathogens.