Jardini Arowana

The Jardini Arowana (Scleropages jardinii) is a species of bonytongue fish in the family Osteoglossidae, native to freshwater rivers and floodplain lagoons of northern Australia and southern New Guinea. Also known as the northern saratoga, it belongs to an ancient lineage of primitive teleosts that has changed little over tens of millions of years. It is a top predator within its native river systems, feeding on prey at or near the water's surface. The species remains widespread and secure across its native range in tropical northern Australia.

The Jardini Arowana shows several distinctive features:

• Elongated, laterally compressed body built for surface-oriented hunting
• Large metallic scales, each outlined with a fine dark reticulated network, giving a bronze-to-green sheen
• Upturned, bony mouth adapted for snapping prey off the surface
• Two short barbels on the lower jaw tip
• Long-based dorsal and anal fins positioned toward the rear of the body, paired with a broad, fan-like tail

It is distinguished from the related Silver and Asian Arowanas by its more variable green-bronze scale coloring and its native range confined to northern Australia and New Guinea.

This species inhabits freshwater rivers, billabongs, and floodplain lagoons across the tropical north of Australia and the southern lowlands of New Guinea. It favors slow-flowing to still water with overhanging vegetation, where surface insects and small animals provide abundant prey. Jardini Arowana tolerate strong seasonal fluctuations typical of the monsoonal tropics, including extended dry-season pooling and wet-season flooding that reshapes their floodplain habitat each year. They generally remain in warm, shallow to mid-depth freshwater rather than deep river channels.

Jardini Arowana are surface-oriented ambush predators, cruising just below the water's surface to detect insects, small fish, and even small animals that fall into the water, which they snatch with a powerful upward strike. They are capable of brief leaps out of the water to catch overhanging prey such as insects or small lizards. The species is a mouthbrooder: after spawning, the male carries fertilized eggs and subsequent free-swimming young in his mouth for several weeks, releasing them only once they are capable of independent feeding. This parental care greatly improves offspring survival compared with egg-scattering species.