Which male sea creature keeps its young in a pouch?

A seahorse is any of the 46 tiny marine fish species in the genus Hippocampus. Seahorses have a horse-like head and neck, as well as segmented bone armour, an erect stance, and a coiled prehensile tail. The male seahorse cares for the female's fertilized eggs in a pouch on the front of his belly, which functions similarly to a female mammal's womb. The female seahorse lays 100 or more eggs in the pouch of the male. The male fertilizes the eggs by releasing sperm into the pouch. The fertilized eggs develop in the pouch's wall and are covered in a fluid that supplies nutrition and oxygen.

The eggs hatch after two to six weeks (depending on the species), and the male seahorse gives birth to live offspring as little as 0.04 inch (1 centimeter) long. Seahorses are mostly found in shallow tropical and temperate salt water, from roughly 45°S to 45°N. They prefer protected environments like seagrass beds, estuaries, coral reefs, and mangroves. From North America to South America, four species can be found in Pacific seas.