Tarciryan (TA some point after 654-TA 913) was the younger son of Sirondil and never sat on the throne of Gondor. However, when his brother Tarannon died without leaving an heir, Tarciryans son Earnil 1 ascended to the throne. Other than this not much else is known about him. 

    Trivia-his name in Quenyan is not fully explained but it is thought to mean something along the lines of “high-ship”