A Meskeen officer.
The so-called "Captain's race", the Meskeen are an amphibious race that resemble terran frogs with digits. They occupy almost the same positions in the Interstellar Concordium as Humans do in the United Federation of Planets, having similar intellectual abilities, ambition, and assertiveness. Meskeen do not die of old age or stop growing, and the oldest members of their race are thousands of years old and five meters tall; however, the average Meskeen is about the same size and composition as a human. (TOS video game: Starfleet Command Volume II: Empires at War)