Black-ray goby mother bird regurgitating food to her chicks. This way, the shrimp and the goby are kept well fed. Sometimes, if the shrimp is not kept well fed, it will resort to killing the goby. In the wild, most burrows are shared by male and female goby pairs, with their respective shrimp partners, and the female goby will use this burrow as a nesting site to lay her eggs. The obvious benefits to both organisms of this symbiotic relationship make the interaction a form of mutualism. Here is an interesting example of this. The other fish is a dartfish (genus "Ptereleotris").
Pinchuk's goby Pinchuk's goby Pinchuk's goby ("Ponticola cephalargoides") is a species of goby native to the Black Sea and the Sea of Azov. The body of adults is prolonged, not very high. Only juveniles have high and short body. Сaudal peduncle is very high (highest between al representatives of genus "Ponticola"), short and flattened from sides (its high is equal its length). The scales on the caudal peduncle are not very big. Head is flattened from sides, snout profile is round, cheeks are round. Superior lip is broad, relatively short. Premaxilla short (especially in juveniles), with sparse strong lips. First dorsal fin