The Number – Cypriniformes
Family – Priniv
The genus/Species – Serrasalmus nattereri
Length: average 20 cm, in some species up to 50 cm.
Mass rarely exceeding 1.5 kg.
Caviar: a few thousand eggs.
The incubation period is 10-15 days, depending on water temperature.
Habits: constant float huge flocks.
Food: primarily fish; attack mammals, floating or come to the waterhole, and birds.
18 known species of piranhas, 4 of which are dangerous to humans, although fatal cases have been identified. Continue reading
Most fish lay eggs, and it is fertilized outside of their body. Fish that spawn, are called oviparous. But some fish give birth to live fry. Such fish are called viviparous.
To live-bearing are guppies, sword fish. The eggs of these fish are fertilized inside the mother’s body and develop there until the fry. At a certain time they are born. This happens 21 days after fertilization.
The number of eggs, fertilized and deferred, differs greatly depending on the type of fish. Some fish lay eggs and abandon her, without showing her any more interest. This is a fish that produce huge amounts of eggs. Those fish that look after their young, they lay only a few eggs.
Caviar can be of two types. One kind of eggs floats on the water surface, the other sinking. The caviar, which floats, is called pelagic. It is usually tiny, bright and contains a lot of protein. Caviar, which is sinking, is called Donna. It is usually harder and more protein in it. Continue reading
Floating jellyfish in the sea often struck by its beauty. Such a wealth of shapes, colors, as among the jellyfish, not to meet many animals! Jellyfish inhabit all seas, and some of these sea animals prefer warm waters of the tropics and subtropics, while others liked the cool Northern parts of the oceans.
Some jellyfish can be found at a depth of 10km, and there are jellyfish that do not leave the coastal strip. It is noteworthy that each type of jellyfish is found only on the territory of the area is an animal does not apply to pandemic, that is common everywhere.
The largest jellyfish is Cyanea arctica – chosen by a cool North sea. The age of lanei can be identified by its colour – older individuals are covered with brown and red spots; the young specimens are painted in an intense orange color. Continue reading