Under this name some kinds of small small fishes, remarkable both on the appearance, and on a way of life are known. Stickle-back differ the prickles before the back fin, two needles on a belly which replace belly fins, the belly board formed by accretion tazovyh of bones, and absence of scales. There are three kinds fresh-water koljushek - stickle-back tryohiglaja, stickle-back devjatiiglaja and green.
Trehiglaja stickle-back. it is armed by three prickles, on each side bodies are the cross-section bone plates replacing scales and gradually narrowed to a tail. Reaches length of 11 sm, weight - 6 Eat Crustacea, hearts, larvae of insects, caviar and malkami fishes. It is used in quality zhivtsa.
Devjatiiglaja stickle-back. Differs a great number of small back prickles which always happens 10 or 9, a naked and more extended body. The size of this stickle-back is even less, than tryohigloj. The length - to 9 sm, weight - Eats 5,5 water bespozvonochnymi. It can be used in quality zhivtsa.