Bellara is a Scheduled Caste in Karnataka, Kerala, Tamil Nadu. Singh reports they speak a dialect of Kannada.
Note: Bellari is a dialect/variety of Tulu.
Unfortunately, I have no idea how to pronounce 'bellari'. Anyway, I assume the community is called beLLAra and the language is called beLLAri.
The Scheduled castes or the erstwhile untouchable castes, in my opinion, mainly came from two backgrounds.
1. Purity and pollution: The communities engaged in so-called polluting occupations, ie. leather works, scavenging etc... were made outcasts.
2. Tribal origins: Many tribal communities as they made transition from tribal life to mainstream life were included in outcasts in old caste Indian society.(Ironically, I believe, ritual purity of tribals was higher than untouchables!)
Now, consider the community beLLAri and the district in Karnataka bordering Telugu speaking Andhra Pradesh, baLLAri. Is it not possible that a region getting its name from a tribe or vice versa?
Therefore, in my opinion, along with zeTTi, baMTe even beLLAra came from Telugu region to Tulu region.