In Vāyupurāṇa(Vayupurana) it is said that Āyu(Ayu) is one of the sons born of the womb of Surūpā (Surupa) , sired by sage Aṇgirā (Angira). Surūpā was the daughter of Sage Mārīci (Marichi).

Vāyupurāṇa(65.105)