SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41fb72727634573112e85db9911f60d769e07e675e4727fe9e5bcf2b1a7f012f' 
  AND token = 'VdJ1YWiQ6qKsHNf8wYTaHQNK+ulVe476aHhwiNv948U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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