According to Bhāgavatapurāṇa (Bhagavatapurana), Ṛta (Rita) was one of the sons born of the womb of Naḍvalā (Nadvala), sired by Cākṣuṣa(Chakshusha) Manu, ruler of the sixth Manvantara.

Bhāgavatpurāṇa Vols. 1-12(4.13.16)