Marble Whiptail Stingray (Fluvitrygon oxyrhynchus)

Marble Whiptail Stingray — Fluvitrygon oxyrhynchus

Long tail. River stealth.

The Marble Whiptail Stingray is a rare Southeast Asian freshwater ray known for its elongated snout and exceptionally long, whip-like tail. Its disc displays soft marbled tones ranging from sandy beige to warm brown, often with subtle mottling that provides natural camouflage over fine substrate. Unlike bold-spotted South American rays, this species carries a more understated, river-worn aesthetic — refined and stealthy.

Native to large river systems in Thailand and surrounding regions, Fluvitrygon oxyrhynchus is adapted to sandy bottoms and moderate flow. It spends much of its time gliding smoothly along the substrate, partially burying itself when resting. The extended tail can reach impressive lengths, giving the species a dramatic silhouette in wide, open-bottom aquariums.

Reaching 18–24+ inches disc diameter with an extremely long tail, this is an advanced-level species suited for serious aquarists with large footprint systems and stable, well-maintained water.

Aquarium Setup

• Minimum Tank Size: 400+ gallons (wide footprint essential)

• Footprint: 6–8 ft length minimum with ample bottom space

• Substrate: Fine sand (critical for health and natural behavior)

• Flow: Moderate

• Décor: Minimal sharp décor; open sandy areas

• Lighting: Moderate

• Filtration: Oversized biological filtration required (heavy waste producer)

• Lid: Secure cover recommended

Tank Mates

Best with large, calm, compatible species:

• Arowana

• Datnoids

• Large peaceful cichlids

• Giant gouramis

• Large catfish

Avoid aggressive fish that may nip the disc and avoid small fish that may become food.

Water Parameters

• Temperature: 78–84°F (25–29°C)

• pH: 6.5–7.5

• Hardness: Soft to medium

• Water Quality: Extremely clean and stable; sensitive to ammonia and nitrite

• Oxygen: Moderate to high dissolved oxygen preferred

Diet

Carnivorous:

• Fresh shrimp and prawn

• Earthworms

• Fish fillet

• High-quality sinking carnivore pellets