SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6deda5a49bf45f9f76689c49c88ddc026a6aa9329b15448c48433d973c680e70' 
  AND token = 'bApioWqYan5vTGJ/8QIAtr/FSgDEtDo0CucvzvKlcTM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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