Macchanu is son of HanumanHanuman
SRI HANUMAN is worshipped everywhere in India, alone... as per that appears in the Cambodian, Thai and other versions of the Ramayana
As per these versions of Ramayana, during one of the battles with Ravana's army, Hanuman encounters one powerful opponent, who looked like Vanara They are generally depicted as humans with monkey-like characteristics who live in forest. They are believed to have supernatural abilities and considered intellectual beings. Hanuman belonged to the same race and had the powers to change his shape and size at his will.from waist-up but had tail of a fish. After a fierce battle, as Hanuman was about to hit the creature with his weapons, a golden star shining in the sky above, reveals by way of aakashwani that the enemy, whom he is going to harm is his own son born by his union with Suvannamaccha, the mermaid daughter of Ravana. Hanuman, immediately holds his weapons in mid-air and father-son duo recognize each other.
Another version of story tells, while following Maiyarab in order to find RamaRama
As of late, in the year 2007, the idea of whether Rama... and Laxmana, who have been abducted by Maiyarab and taken to his kingdom in netherworld, Hanuman reaches a pond, where he encounters Macchanu. The fight between them is indecisive, therefore, Hanuman is surprised and asks his opponent, who is he. MacchanuMacchanu
Macchanu is son of Hanuman as per that appears in the Cambodian, Thai and other versions of the Ramayana... introduces, himself as son of Hanuman and SuvannamacchaSuvannamaccha
Hanuman, building a causeway, discovered that he was hampered by mermaids underwater. When Sita is kidnapped her husband Rama enlists Hanuman's aid in rescuing her... and so they finally identify and embrace each other. He tells Hanuman that Maiyarab, is his foster father, who had picked him up lying on sea shore, where his mother had left her.
Although, he does not want to betray Maiyarab but tells Hanuman through a riddle the entrance to the netherworld lies inside the lotus in the pond he was guarding.