Holapogon maximus, the titan cardinalfish, is a species of ray-finned fish in the family Apogonidae, the cardinalfishes. This species is the only known member of the genus Holapogon. It is native to the Arabian coast and the Gulf of Oman, and it has recently been recorded from the coast of India. It lives at depths of from 83 to 100 m (272 to 328 ft). This species grows to a total length of 25 cm (9.8 in).