What animal is the symbol of the second Tirthankara Ajitanatha?

The animal symbol of the second Tirthankara Ajitanatha is the elephant.

Ajitanatha, also called Ajitanatha or Ajitanatha Bhagavan, is the second Tirthankara of the present Jain time cycle. Jain tradition places his birth at Ayodhya, or Saketa, in the Ikshvaku dynasty. His parents are identified as King Jitashatru and Queen Vijaya. The elephant is his lanchhana, or identifying emblem, used in Jain art to distinguish his images from those of other Tirthankaras.

Both major Jain traditions, Śvetāmbara and Digambara, associate Ajitanatha with the elephant, so this answer is not a sectarian variation. He is traditionally shown with a golden complexion and is linked with the saptaparṇa tree. His attendant deities are named Mahayaksha and Ajita Yakshi in Śvetāmbara tradition, while Digambara sources give Rohini as the yakshi.

A common mix-up is with Rishabhanatha, whose emblem is the bull, or Mahavira, whose emblem is the lion. Ajitanatha’s successor, Sambhavanatha, is represented by a horse.