named Yauvanāśva — SB 9.7.1plugin-autotooltip__small plugin-autotooltip_bigŚrīmad Bhāgavatam 9.7.1

Śukadeva Gosvāmī said: The most prominent among the sons of Māndhātā was he who is celebrated as Ambarīṣa. Ambarīṣa was accepted as son by his grandfather Yuvanāśva. Ambarīṣa's son was Yauvanāśva, and Yauvanāśva's son was Hārīta. In Māndhātā's dynasty, Ambarīṣa, Hārīta and Yauvanāśva were very prominent.

the son of Yuvanāśva — SB 9.6.33-34plugin-autotooltip__small plugin-autotooltip_bigŚrīmad Bhāgavatam 9.6.33-34

Māndhātā, the son of Yuvanāśva, was the cause of fear for Rāvaṇa and other thieves and rogues who caused anxiety. O King Parīkṣit, because they feared him, the son of Yuvanāśva was known as Trasaddasyu. This name was given by King Indra. By the mercy of the Supreme Personality of Godhead, the son of Yuvanāśva was so powerful that when he became emperor he ruled the entire world, consisting of seven islands, without any second ruler.