Spined loach (Cobitis taenia) is a freshwater fish of the family Cobitidae. Length is 8-10, rarely 12 cm. It has two pairs on the upper jaw and one pair of antennae at the corners of the mouth. Under the eyes is a retractable spike, sometimes hidden in the skin. Widely distributed in European water bodies (except rivers of the Arctic Oxan basin). It inhabits rivers with shallow currents and lakes. It inhabits shallow waters with stony, sandy-silt substrate and sparse vegetation. It leads a solitary way of life. Matures in the second or third year of life. Spawning in late April-May at temperatures not lower than 16°C, portioned. Fecundity up to 300 eggs. Feeds on bottom invertebrates. Numerous. Not of commercial importance. Occurs in the beds of large and small rivers, large and small lakes, ponds and reservoirs. Prefers both shallow areas with stony, sandy and muddy ground and deep-water biotopes. It has no commercial importance.

Inhabit freshwater bodies of Eurasia and North Africa in Morocco. In Siberian water bodies, in the Selenga basin inhabits Cobitis melanoleuca. There are 177 species united into 26 genera and two subfamilies - Cobitinae and Botinae.

Body elongated, compressed from sides or spindle-shaped, covered with fine, sometimes hidden in the skin scales or naked. Mouth lower, small, without teeth. The antennae around the mouth are 6-12. The pharyngeal teeth are single-rowed. There is a webbing apparatus. Eyes small. Swim bladder partially (anterior part) or completely enclosed in a bony capsule. The dorsal and anal fins are very short. The nostrils are elongated into small tubes. Larvae breathe with the help of external gills.

The coloration is very variegated. The general background of the back is yellow or sandy yellow, the belly and flanks are light yellow. On this background stripes of black-brown spots of different sizes are clearly distinguished. One row of large roundish spots goes in the middle of the back, below it is a band of small speckles, then - a row of larger rounded or oblong, merging with each other spots, then - again a band of small speckles, and then, along the middle of the flank - a band of large irregularly shaped spots. At the end of the body, behind the dorsal fin, this pattern becomes less distinct, the stripes seem to merge into a continuous marble pattern. On the head scattered small irregularly shaped spots, a dark band goes from the end of the snout through the eye. Small spots form stripes on the light-colored dorsal and caudal fins, the rest of the fins without spots. At the end of the body at the base of the caudal fin in the upper part of the well visible dark spot in the form of a comma or bracket. Coloration - a very important feature that allows you to recognize different species of these fish. During the spawning period, it becomes brighter, many spots in the stripes merge with each other, and the stripes even more contrastingly stand out on the body. And if in the pre spawning period mottled coloration Spined loach can be considered a means of camouflage against the background of the bottom, then in the spawning period it clearly serves as a signal, attracting ready to breed individuals of the same species.

In Spined loach the differences between individuals of different sexes are very well pronounced. Males are not only smaller than females, which is also found in other fish species, but they also have much longer pectoral and pelvic fins, and, finally, they have a peculiar organ, the so-called Canestrini organ. This is a special small bony plate on the longest ray of the pectoral fin, covered with skin. In different species of fish, the shape of this plate is different. In the Spined loach it is wide and resembles the shape of a rounded axe.

Representatives of this family are small freshwater fish that have mastered various types of water bodies: from mountain rivers to flat swamps. Thanks to their well-developed skin and intestinal respiration, they are able to live in oxygen-poor environments. Almost all finches are benthophagous and periphytophagous, feeding at dusk and night, and burrowing into the ground during daylight hours. Spined loach mainly inhabits rivers with slow flow, lakes, and also small rivers with fast flow. It usually stays near the bottom in areas with stony, sandy or muddy bottom. Often buried in the sand. You can see the pincher and among thickets of filamentous green algae, on which it hangs, peculiarly curved, resembling a small lizard hidden in the grass. The fish feeds on small bottom invertebrates and insect larvae, and is most active in the evening hours.

In spring, Spined loach go to shallow waters, enter small rivulets and spawn here among algae. In southern areas spawning begins in May, and in our middle zone - in June. The eggs are large (about 2 millimeters in diameter), between the embryo and the shell of the egg there is a large watery space that allows the eggs to develop in suspension among filamentous algae. After a few days, larvae emerge from the eggs, which are also kept among the algae. In quiet areas where the puffer spawns and its larvae develop, there are sharp fluctuations in the oxygen content of the water. Therefore, soon after hatching, the larvae develop special external gills. Adult fish for survival in unfavorable oxygen conditions resort to additional respiration with the help of intestines.

Spined loach spend the whole summer time in shallow water, and in the fall they migrate to the main river channel to deeper water, where they spend the winter. The Spined loach is usually abundant in its habitat. This species is of no economic importance. In Western European countries (e.g. Italy), similar species are used as bait in sport fishing.