why did this show up in my eth wallet?
If it showed up in your wallet without mining it, it was probably someone spoofing 0xBTC with that Ethereum "exploit" that recently came to light...basically people can make their own coins that look like others and spam them to everyone that has ETH. Has nothing to do with 0xBTC but check the contract address I bet it's not really 0xBTC

Hi Dev.. im mining with my CPU
Address: 0x2d7B3bfF39DDaDE400CCE86EDC83dC20B54124F1
Accumulated Shares: 1230
Balance: 360849
Vardiff: 205
Using Custom Vardiff: false
Hashrate: 2.08 Mh/s
But when i check on my MEW token balance stil 0 (zerro)
What happen?
All pools have a minimum payout of around 10-15 coins. If you are mining with your CPU this may take a very long time...your balance of "360849" is currently only .00360849 0xBTC.