Siyokoy

The siyokoy is a water creature with scaly skin, webbed hands and feet, and sometimes fins or gills. Compared with the sirena or the kataw, which look more human, it is described as more like an animal. Some stories give it human legs and a green, muscular body with sharp teeth and bulging eyes. Others add tentacles. Tellers say it lives in the sea, rivers and lakes, and drags fishermen under to drown them. Most stories show it as hostile.

The word may come from Hokkien shui gui, "water ghost." In Chinese belief, a shui gui is the spirit of a drowned person who pulls others under. A Spanish-era record also lists siukuy as an old Tagalog god of rivers, and some writers link the two words. This link is a theory about the name. It is unclear whether the belief itself came from Chinese traders, from older Tagalog ideas, or from both.

Stories of the siyokoy are told by Tagalog and Visayan speakers, and in many places along the coast. Today it appears in children's books, comics and television as a scary sea monster.