He ruled from 135 till 141 AD. He was preceded by his father in law, Gajabahu I and succeeded by his son, Bhatika Tissa.
Mahavansa/Chapter 35 tells ....After Gajabãhu's death the king's father-in-law Mahallaka Naga (135-141 AD) reigned six years. (The viharas) Sejalaka in the east, Gotapabbata in the south, Dakapasana in the west, in Nagadipa Sälipabbata, in Bijagama Tanaveli, in the country of Rohana Tobbalanugapabbata, in the inland country Girihälika: these seven vihäras did the king Mahallaka Naga, ruler of the earth, build in the time (of his reign), short though it was. (Mahallaka →Mahala)
Mahavansa/Chapter 36 (The Thirteen Kings) tells....After the death of Mahallaka Naga his son Bhatika Tissa reigned twenty-four years in Lanka. He built a wall around the Mahävihara. When the king had built the Gavaratissavihara he made the Mahamani-tank and gave it to the vihara. Moreover, he built the vihãra called Bhätikatissa. He built an uposatha-house in the beautiful Thuparama; the king also made the Randhakandaka-tank. Filled with tenderness towards beings and zealous in reverencing the brotherhood the protector of the earth commanded lavish alms-giving to the community of both sexes. (Mahallaka→Mahala)