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单词 polypterus
释义

Polypterus


Po`lyp`te`rus


n.1.(Zool.) An African genus of ganoid fishes including the bichir.

polypterus


polypterus

(pəlĭp`tərəs): see bichirbichir
, common name for African freshwater fishes as of the family Polypteridae, and particularly for those of the genus Polypterus. Bichirs are among the most primitive of the ray-finned fishes, or Actinopterygii, the dominant group of modern fishes.
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Polypterus

 

a genus of fishes of the superorder Polypteri. The body is elongated (up to 120 cm long) and slightly laterally compressed. The pectoral fins have a fleshy lobe at their base; the dorsal fin consists of a number of small fins, each of which has a rigid anterior ray. The ventral fins are placed far to the rear. The body is covered with ganoid scales. The swim bladder is double and alveolate; it opens ventrally and acts as a lung. The fishes rise to the surface for air. If they are deprived of atmospheric air, they die within two or three hours; however, they cannot live outside the water.

There are ten species of Polypterus, inhabiting the quiet back-waters of rivers and lake lagoons in Africa. They feed on small fish and invertebrates. The fishes spawn from July to September (during the rainy season); the roe are small (up to 1–3 mm) and strongly pigmented. Larvae with external gills emerge from the roe. Polypterus is of minor commercial value. The flesh is tasty. Some species are kept in aquariums.

REFERENCES

Nikol’skii, G. V. Chastnaia ikhtiologiia, 3rd ed. Moscow, 1971.
Zhiznzhivotnykh, vol. 4, part 1. Moscow, 1971.

Polypterus


Polypterus

a primitive freshwater fish of Central Africa derived, with sturgeons, from Devonian palaeoniscid stock. see PALAEONISCUS.
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