SAO PAULO/MEXICO CITY, Jan 11 (Reuters) - Brazilian retailer Americanas SA (AMER3.SA) said on Wednesday its chief executive and chief financial officer resigned after the discovery of around 20 billion reais ($3.88 billion) in accounting "inconsistencies." Lojas Americanas CEO Sergio Rial departed less than two weeks after taking the job, when he replaced Miguel Gutierrez. Joao Guerra, a long-time Americanas executive not involved with accounting or financial management, will take over as CEO on an interim basis. The amount of accounting inconsistencies is larger than the company´s net equity, 15 billion reais, said Fabrício Gonçalvez, CEO at Box Asset Management. The amount is also almost twice Americanas' 10.7 billion reais market capitalization, according to Refinitiv data.

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