Merpeople

"The oldest recorded merpeople were known as sirens (Greece) and it is in warmer waters that we find the beautiful mermaids for frequently depicted in Muggle literature and painting. The selkies of Scotland and the Merrows of Ireland are less beautiful, but they share that love of music which is common to all merpeople."

- Fantastic Beasts and Where to Find Them

Merpeople are sentient beings (or beasts, as they want nothing to do with the likes of vampires and hags) that live underwater, and are found all over the world. Their customs and habits are mysterious, and, like the centaurs, they refused being status in favour of beast. Merpeople can breathe above the waves for a time, but it is unclear if they can ever truly leave their habitat.

Description
The merpeople of Hogwarts have greyish skin and long, wild, dark green tentacles. Their eyes are yellow, as are their broken teeth, and they wear thick ropes of pebbles around their necks as necklaces. Their powerful, silver fish tails allow them to swim expertly, while the upper parts of their bodies resemble those of humans. Merpeople are also very tall, and during the second task, Harry encountered one in the lake near Hogwarts who was seven feet tall with a long green beard and a choker of shark fangs, carrying a spear. They have been known to keep Grindylows as pets, and use Lobalugs as weapons. One tribe even managed to capture and domesticate a Hippocampus.

History
They were used during the Triwizard Tournament of 1994. A year later, Sirius Black revealed that Dolores Umbridge once requested the Ministry to have Merpeople rounded up and tagged, due to her hatred to half-breeds, though Merpeople are in fact a separate species of their own, not a mixed species between fish and human. Regardless of Umbridge's misunderstandings and hatred, this suggestion was never put into practice.

Society and Culture
Merpeople society is based around organised communities, and they have a great love of music. Their language is known as Mermish, and only a few wizards know how to speak it. However, since their language can only be heard properly underwater, it sounds like a loud screeching when spoken above water.

Sub-species
The term "Merpeople" is an umbrella term. There are several distinct sub-species around the world. Sirens of Greece are the earliest recorded Merpeople, and are often depicted in Muggle literature and paintings as beautiful women who sing to lure sailors to their deaths. The Selkies of Scotland, and the Merrows of Ireland, are less pleasing to the eye. However, despite their physical differences, they all retain their love of music.

Behind the scenes

 * According to W.O.M.B.A.T., it is possible that freshwater merpeople are less warlike than salt-water merpeople.
 * In LEGO Harry Potter: Years 1-4, the merpeople actually attack, whereas in the film and book they only confronted Harry when he tried to take more than his own hostage, but even then they only threatened to attack.
 * In the handheld versions of LEGO Harry Potter: Years 5-7, there are merpeople living in the Forest of Dean lake.
 * Mirabella Plunkett transfigured herself into a haddock after she was forbidden to marry a merman whom she was in love with.
 * In Harry Potter and the Half Blood Prince, the merpeople are described to have purple hair. However, in the LEGO set, the merperson included has reddish (also decscribed as blood-red) hair. Also, in the film, the Merpeople's hair is more yellow than green.

Appearances

 * Harry Potter and the Goblet of Fire
 * Harry Potter and the Goblet of Fire (film)
 * Harry Potter and the Order of the Phoenix
 * Harry Potter and the Half-Blood Prince
 * Harry Potter and the Half-Blood Prince (video game)
 * Fantastic Beasts and Where to Find Them
 * Harry Potter: A Pop-Up Book
 * LEGO Harry Potter: Building the Magical World
 * LEGO Harry Potter: Characters of the Magical World
 * LEGO Harry Potter: Years 1-4
 * LEGO Harry Potter: Years 5-7
 * Harry Potter LEGO Sets
 * Pottermore