SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '532745a5189778cd7b53e7b83a51cf9be6c96db7642da3e1cdef499ba15bf852' 
  AND token = 'TEuTfIgonsQYm4HrNMllW9wdcvHn45bL2+X1UkGqzhQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}