Although he is not from the Noh family, but his younger brother Yuji TANIGUCHI (real name: Yuji NARITA) is also a Noh actor who plays otsuzumi-kata in the Ishii school.
能の家の出身ではないが、弟の谷口有辞（本名・成田有辞）も大鼓方石井流の能楽師。