This list of mythical creatures that begin with this letter and I am constantly gathering information from each continent, and is continually being updated.
Hudhud (Islamic mythology)
Hudhud was, according to the Quran, the messenger and envoy of the prophet Sulayman. It refers to the sagacious birds in Islam, also referred to in The Conference of the Birds, a Persian poem by Attar of Nishapur as the "king of birds". The bird appears twice in the 27th chapter of An-Naml. Hudhud, as described by the Quran played an important role between Sulayman and Queen of Sheba while carrying messages between the two.
Huhhud, according to an uncertain Iranian legend, was originally a married woman. Her father-in-law entered the room and found her in an uncovered state when she was combing her hair. It was embarrassing to her, so she flew with the comb on her head. Thus, the bird became known in Persian language as (scallop headed).