Lord Shiva in the temple is a swayambumurthy. There are two Goddesses in the temple against one normally seen in Shiva temples. They are in separate shrines. There is a hole on the body of Shivalinga made by a Karkadam -Cancer (Nandu in Tamil) a sea creature and an injury scar caused by Indira.
Sage Durvasa was mocked at by a Gandharva that he was walking like a cancer-nandu. The sage was just completing his Shiva Puja. The angry sage cursed him to become a Nandu. When he begged for pardon, the sage advised him to worship Shiva for relief. He followed the advice and got relieved. As the Lord graced the Nandu-Karkadaka- He is called Karkadeswarar. Indira the king of Devas, following the advice of his Guru Prahaspati, worshipped the Lord here with 1008 flowers daily after a dip in Pushkarini and corrected himself for the wrongs he committed. Tirundhu means correcting oneself. Devan is Indira. Hence the name of the place is Tirundhu Devan Kudi. Locals know the place only as Nandu Koil.