SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b8d056416a18bb00e6e774ebee55f129f54468d8211670bb0cdd29593eabfb6' 
  AND token = 'q0MowsyiwItcUMSBbS7uWwpsLqEW10EtclHQjMjxbiA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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