Beady pipefish (Hippichthys penicillus) is distributed in the western Pacific Ocean, Indian Ocean, Australia, and so on. In Japan, it is found in the southern part, and often in the waters near Kyushu. It lives in shallow inner bays and estuaries. It hides in the shadow. It enters the brackish waters, but does not seem to enter the fresh waters. It grows to a total length of about 18 cm. The body surface is rough. The spawning season is early summer. A male has a childcare sac. Zoophagous. It eats small fish and crustaceans.