Speartooth Shark

Glyphis glyphis is a critically endangered euryhaline carcharhinid shark found in the brackish tidal rivers and estuaries of northern Australia, New Guinea, and Borneo. It is one of the least-known sharks on Earth, with a total global population estimated in the low hundreds. Its small, paddle-shaped upper teeth give the species its common name. It inhabits turbid tidal rivers with strong currents and murky water, where its small, electroreceptive eyes are supplemented by an acute lateral line system for prey detection.

This listing exists purely for conservation education purposes. No private individual should attempt to acquire, keep, or trade Glyphis glyphis — it is protected under CITES Appendix II and Australian and international law. Any captive specimens that do exist are held exclusively by major accredited aquaria as part of coordinated conservation programmes. The species' inclusion here reflects its extraordinary conservation significance and the importance of public awareness.

Encountering this species in a responsible institution is a privilege that underscores the fragility of freshwater megafauna worldwide. Supporting freshwater shark conservation through legitimate channels — research foundations, certified conservation organisations — is the appropriate action for anyone who finds this species compelling.

Water: 24–30°C, pH 7.0–8.5, brackish to marine; strong tidal current; immense volume. Tank: 50 000 L minimum (accredited institutions only); saltwater/brackish system; maximum biosecurity. Feeding: Whole fish and crustaceans; fed by trained staff under institutional protocols. Breeding: Under investigation in accredited programmes only. Compatibility: Listed for conservation education only — not available for private purchase.