edit by kai_schablewski:

This taxonchange affected some IDs of the plants that are commonly sold as Spiraea arguta but are actually the artificial hybrid between Spiraea cantoniensis and Spiraea trilobata. The correct name for these plants is Spiraea × vanhouttei.

http://www.plantsoftheworldonline.org/taxon/urn:lsid:ipni.org:names:1011556-1

Because this taxonchange was already committed i have added the name Spiraea × arguta as synonym to Spiraea × vanhouttei that it is easier in the future to find the correct taxon name.

It is not identical with the Spiraea arguta Hoffmanns. that is a synonym of Spiraea salicifolia L.