Sources and the Limits of the Record
The principal witness to this martyr is the liturgical calendar itself. The synaxarion preserves his name, his rank as a martyr, his epithet "the Dacian," and his commemoration on June 22, but no narrative of his birth, the circumstances of his death, or any relics or shrines associated with him. The Orthodox Church in America states plainly that no account of his life is currently available.
Because he appears on the same date as the Hieromartyr Niketas of Remesiana and shares a name and Danubian setting with the Great Martyr Nicetas the Goth, care is needed not to merge the three distinct commemorations. In the absence of a surviving passion or vita, Niketas the Dacian is best regarded as an honest entry awaiting further scholarly and ecclesial confirmation.