Possible Clues:

• Mexican walking fish, a salamander
• Tiger salamander's cousin
• Mexican salamander, its name meaning 'water servant'
• Amphibian called the Mexican walking fish
• Critically endangered amphibian species whose only natural habitat is Mexico City’s Lake Xochimilco
• Walking fish lax about accepting love and fate
• Amphibian that Ogden Nash once rhymed with 'bottle'
• Many loath at first to grab cross old salamander
• Salamander planned to be added to the design of Mexico’s 50-peso note by 2022
• Too lax, somehow, beginning to look after this amphibian