This just recently happen to me with a BTS/BTC transaction on metaechange. It was not scanning when I did the transaction. I don't know if it helped anything, but I entered "scan 3315013 1" in the console, and it returned with "OK" I entered "scan_transaction a8d2636a" and it came back with this:
TIMESTAMP BLOCK FROM TO AMOUNT MEMO FEE ID
2015-08-13T14:51:43 3315013 gminer6626 liquidusd 4.9032 USD bitUSD_BTC-0-1HaWGqESa1jZzRzRtKquZ 0.00000 BTS a8d2636a
The client is also rescanning bitshares transaction history (joy
) It didn't show up in metaexchange again, so im guessing it's a glitch.