| | | Kind of type | Full locality |
| | | unspecified primary type of synonym Isocapnia fumosa Banks, 1938 | Northwestern U.S.A., Oregon: Oregon National Forest, Herman, Oregon |
| | | unspecified primary type of synonym Isocapnia fumosa Banks, 1938 | Northwestern U.S.A., Oregon, Lane County: Junction City |
| | | holotype of synonym Capnia fumigata Claassen, 1937 | Northwestern U.S.A., Oregon, Benton County: Alsea |
| | | syntype of species Isocapnia grandis (Banks, 1907) | Western Canada, Alberta: Banff |