EastScape Wikibuilt from the game itself

Primeval melon seeds

Where to find it: The Deep Wild (Caveman; Sabretooth), The Primeval Valley (Sabretooth), Thornspire Crown (Thornback Stag).

“Plant them on your island (Harvesting 85). They grow primeval melon, and give their seeds back.”

Dropped by

MonsterLevelHow manyChance a killRoll
Thornback Stag1151–24.8%One of the table
Caveman9011.3%Own roll
Sabretooth9311.3%Own roll

Grows

Plant it on your island's plots (Harvesting 85): ready in about 420 minutes, logged in or not.