Matsya Purana — Kārtavīrya Arjuna’s Solar Boon and the Genealogy from Kroṣṭu to the Yādava Lines
तस्मिन्प्रवितते यज्ञे अभिजातः पुनर्वसुः अश्वमेधं च पुत्रार्थम् आजहार नरोत्तमः //
tasminpravitate yajñe abhijātaḥ punarvasuḥ aśvamedhaṃ ca putrārtham ājahāra narottamaḥ //
When that sacrifice was underway, the well-born Punarvasu was manifested; and that best of men then performed the Aśvamedha, desiring a son.
This verse does not discuss Pralaya; it focuses on dynastic continuity through ritual—specifically the undertaking of an Aśvamedha to obtain progeny.
It presents a royal ideal in which a ruler pursues legitimate aims (like heirs and continuity of the lineage) through dharmic means—public Vedic sacrifice—rather than through adharmic action.
The ritual significance is the Aśvamedha performed with the intention of securing a son; it highlights yajña as a sanctioned means for desired results (phala) within Vedic-Puranic ritual culture.