Joe Slankas, assistant v.p. of credit derivatives trading at Merrill Lynch in Tokyo, left the firm last month. He reported to Shinichi Minohara, managing director of credit derivatives in Tokyo. Slankas has moved to New York, according to traders familiar with the situation. It could not be determined if he had taken another job. Minohara said he will look to hire internally to replace Slankas, declining further comment. Slankas could not be reached for comment.