Matsya Purana — Ila–Sudyumna Episode and the Expansion of the Ikṣvāku
आनर्तस्याभवत्पुत्रो रोचमानः प्रतापवान् आनर्तो नाभ देशो ऽभून् नगरी च कुशस्थली //
ānartasyābhavatputro rocamānaḥ pratāpavān ānarto nābha deśo 'bhūn nagarī ca kuśasthalī //
Ānarta had a son named Rocamāna, a radiant hero of great might. From Ānarta arose the Nābha region, and the city called Kuśasthalī.
This verse does not describe Pralaya; it preserves dynastic memory by linking a king (Ānarta) to a descendant (Rocamāna) and to the emergence/naming of a region (Nābha) and a city (Kuśasthalī).
By praising Rocamāna as pratāpavān (valorous/powerful), the verse reflects the Purāṇic ideal of kingship—protective strength and public order—while also grounding royal duty in lineage continuity and the founding of stable settlements.
The verse is primarily geographic-genealogical; its practical takeaway is the naming/founding of a city (Kuśasthalī), a motif often used in the Matsya Purana to connect righteous rule with the establishment of enduring urban centers (useful for readers seeking Matsya Purana sacred geography and settlement traditions).