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Polypterus delhezi


Polypterus delhezi
Armoured Bichir
斑节恐龙
The armoured bichir or banded bichir (Polypterus delhezi) is a snake-like fish that ranges from the Congo River, specifically in the upper and middle portions.
P. delhezi have greyish backs and sides, with specks of yellow or green coloration. The ventral surface tends to be lighter, closer to cream than grey. P. delhezi has a smaller mouth compared to its body and to other fish in its family, and is distinguishable from other species by the 7 to 8 dark vertical bands, which can vary in thickness between individuals. It has 13 to 13 dorsal finlets

An incredibly hardy, nocturnal species with very poor vision, Polypterus delhezi relies on its excellent sense of smell to locate food. This species, along with others of its genus, is one of the last surviving relatives of very ancient species. Fossils of earlier relatives have been found that date back to the Triassic Period, which occured during the early development of the dinosaurs more than 200 million years ago. 

They have several interesting adaptations. The swim bladder is divided into 2 parts, of which the right hand section is considerably larger. This functions as an accessory breathing organ and means the fish can survive out of water for some time, provided it is kept moist. Like Ananbantoid species, this fish may actually drown if it is denied access to atmospheric air. 
Young bichirs have amphibian-like external gills which are lost as the fish matures. This, coupled with their nocturnal mode of hunting, in which they emerge from their daytime refuges to hunt invertebrates and small fish in shallow water, clearly exhibits the link these species form between fish and amphibians. 

Polypterus delhezi is one of the "upper-jawed" tribe of polypterids so named on account of the upper jaw being longer than or equal in length to the lower jaw.
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