This list of mythical creatures that begin with this letter and I am constantly gathering information from each continent, and is continually being updated.
Makara (Indian mythology)
Makara appears as the vehicle of the river goddess Ganga, Narmada, and of the god of the ocean, Varuna. Makara are considered guardians of gateways and thresholds, protecting throne rooms as well as entryways to temples; it is the most commonly recurring creature in Hindu and Buddhist temple iconography, and also frequently appears as a gargoyle or as a spout attached to a natural spring.
Makara-shaped earrings called Makarakundalas are sometimes worn by Hindu deities, for example Shiva, Vishnu, Surya, and Chandi. It is generally depicted as half terrestrial animal in the frontal part (stag, deer, or elephant) and half aquatic animal in the hind part (usually of a fish, a seal, or a snake).