SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c14ddc35edff52ebb4a25022cd4f98d9f96d626689a0b7e9b923bcdb493648b9' 
  AND token = 'yZbScoOkFHYGQ5KF6HkaOEvuROwQUUiid6u/nKfbLgs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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