SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a72f7e9e0909df58ba593cd6f53eb5cc1325f8fe9e9126ba87dc5a42e4d58540' 
  AND token = 'f8mYwrW3vN9L12dhqhmE9VjcK8jBSE2yPl3gtl22A2Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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