SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dda08ba5f7bd79a47f99766160b864558ea28ff6368200c02bffd4275aa585ca' 
  AND token = 'B630bBxhFn2tk895apVU1nKMrs1FUDuf5hWLO47Txq8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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