Private First Class Richard S. Karlson, U. S. Marine Corps, was killed in action - or died of wounds sustained - during the fighting on Saipan, which is in the Mariana Islands.
The database referred to is sponsored by the ABMC but produced by a private firm, which is why much of the info therein is either incorrect or incomplete. You can access it at < http://www.americanwardead.com/searchww.htmhttp://www.americanwardead.com/searchww.htm > (simply click on the address).
The service number given is incorrect. There's a memorial inscription honoring him at the National Memorial Cemetery of the Pacific, Honolulu, Hawaii. Apparently no remains were recovered. This suggests he may have disappeared in an explosion or was somehow dismembered to the extent that no identifiable remains were found.
Had he died on board a hospital ship, is remains would have been preserved and interred in the temporary military cemetery at Saipan.