The Sea Horse is a cryptid mentioned at Chiloé Island. It is, according to Latcham  a creature that neighed strongly, foamed at its mouth and being very large, could fit up to twelve native wizards on its back.
Chilean explorer, Guillermo Cox wrote that one of his guides, Pedro Oyarsún had once seen a dead “sea horse” on the beach, “its mouth hurt by the bit, black and white [skin] and very short legs like those of a sea wolf”.
In Latcham’s opinion, this creature was the native’s distorted view of a sea elephant (Macrorhinus leoninus) which was once abundant in Chile but had been hunted to extinction. The largest member of the seal family, its long snout—40 cm (16 in.) in length— could have seemed like a horn; its imposing size, up to 5 m (16.4 ft.) long and 4,000 kg (8,800 lb.) and aggressive behavior in males also resemble the fierceness and enormity of the sea horses.
The quote shown above, reads:
The sea horse is the same as the river horse or hippopotamus, which is found in the African rivers; it is different however in that it has a mane on its nape.
He goes on to add that: "I did not have the chance to see the sea horse. Following the description of some who saw it under water, I thought that it was not different to the African hippopotamus. Later, others who have seen it out of the sea, have told me that it has roughly the height of a ordinary horse, which it colosely resembles in its head, tail and back."
And it is the second time that I find a reference about the strange Patagonian hippopotamus.
 Latcham, R., (1924). Op. Cit. pp. 611+
 Cox, G. Op. Cit. pp 70.
 José Toribio Medina. (1878) Colección de historiadores de Chile y documentos relativos a la historia nacional. Imprenta del Ferrocarril. Vol. 11. pp. 295. and 302
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia2010 International Year of Biodiversity Copyright 2009-2010 by Austin Whittall ©