Need help identifying this piece of bone(?) found in southeast brazil

A freediver discovered an intriguing piece of bone while exploring the sandy seabed approximately 50 meters from the shore in southeastern Brazil. The item was found partially buried and raises questions about its origin and significance. This inquiry seeks input from knowledgeable individuals who may be able to identify the bone and provide insights into its potential history or relevance. Any expertise or guidance on this discovery would be greatly appreciated. Thank you for your contributions to this fascinating discussion!