SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '103e3d9a1e79c2bbdfbac1a6ff24e79579620ff90b72999c02941db40a59e9fc' 
  AND token = 'W20WIBFWPWqpCR/iqs2BhkSQUfCkvYi6dGw1sJzbu0Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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