It is narrated from Sayyiduna Jabir (may Allah be pleased with him) that once a monitor lizard was brought to the Noble Prophet (peace and blessings be upon him). The Prophet (peace and blessings be upon him) refused to eat it and said: I do not know, it may be from among those towns and times that were transformed.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 14460
Hadith Gradingحکم دارالسلام:إسناده صحيح، قوله: « لعله من القرون الأولى » قال السندي: « يدل على أنه قاله اجتهادا وظنا، وقد جاء ما يدل على عدم بقاء الممسوخ »