Knoutsodonta jannae is a species of sea slug, a dorid nudibranch, a shell-less marine gastropod mollusc in the family Onchidorididae.

[3] This species was described from Tyee Point, Copper Cove, British Columbia, Canada, (49°22′8″N 123°16′5″W / 49.36889°N 123.26806°W / 49.36889; -123.26806).

It is currently known from Prince William Sound, Alaska south to Lion Rock San Luis Obispo County, California.

[4][1][5] A specimen from Pillar Point, San Mateo County, California was sequenced for the genes 16S, partial 18S, partial 28S, Histone H3, and the DNA barcoding Folmer region of Cox1 and a specimen from Prince William Sound, Alaska was sequenced for 16S and H3 in an investigation which established the genus Knoutsodonta.

were found feeding intertidally on the orange bryozoan Lyrula hippocrepsis.