An early ancestor of Asian Arowana was discovered. Scientists have long considered that Scleropages formosus, Arowana, or dragon fish is a zoogeographical mystery. This is mainly because of lack of fossil records. Most of the specimens collected previously were limited to scales, bone fragments or otoliths only.
The Arowana is among the most expensive and prized fishes mainly because they are difficult to breed. The Arowana demands delicate care, high-quality fresh water, and high-quality food. According to Quora user Santhosh Jain, Arowanas also breed fewer when it reaches the old maturity age of 5 years. Other pet owners claim that the reason behind the dragon fish's price is its link to Chinese Feng Shui as a good luck charm.
To trace the origin of this expensive fish, a fossil record of Arowana's prehistoric cousin Scleropages sinensis was found and dates back to the early Eocene period. This discovery provided a link and a step further to solving the evolution of the prized dragon fish. The Arowana fossil that the Chinese Academy of Sciences now owns is extremely rare, Phys.Org reported. In fact, the fossil is the first ever discovered that is in a complete and exceptionally pristine state.
Scleropages sinensis resembles modern Arowana in terms of skull bones, shape, the position of fins and even the scales. This observation gave substantial evidence that it belongs to the same genus as that of present dragon fish. At any rate, there are some notable differences as well. The Arowana fossil yields evidence of larger antorbital sensory pore, a pectoral fin that is very long, shorter parapophyses, among others.
Scientists also suggest that the Scleropages sinensis is closely related to the Scleropages formosus rather than the Scleropages leichardti. The formosus Arowana is living in near-static state rivers which move slowly. This Arowana variant is carnivorous and lives on insects, small fishes, worms and even larger animals like birds. Comparably, the Sinensis dragon fish that lived in the Eocene period possess the same attributes.
