If you were talking about a single day, my best would be 9 species. Some friends and I set up the Ozark Slam, which is catching a rainbow and brown trout, and a largemouth, smallmouth, and rock bass all on the same day. So far we have done this a couple of times and had to fish two different rivers/creeks to complete the slam. On one of those trips I caught brown and rainbow trout, banded sculpin, northern rock bass, largemouth bass, smallmouth bass, green sunfish, bluegill sunfish, and long-eared sunfish. Again I was not targeting any smaller species or else the total could have been higher.