SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2281fdf52c2c6f4f11f6601b07b6933c53d1cff9133be9436d7d8ca79c0dc29a' 
  AND token = 'N2uVRqmJopIBjTsZOsjmmYbzAHwxbleDEHd5DpIpAzs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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