SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ad33444353aa9edad8489619106dddde4920b8830d9939f78ebd275e42aa22c2' 
  AND token = 'pdh4Ung6CrvacAUBkyd7Qe0BYQz/okUGv82oijIqgXU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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