| Tetraedron minimum | | 1990-06-26 | 1990-06-26 | Tretjønnet (Agder, Norway) |  |
| Tetraedron minimum | | 1989-09-19 | 1989-09-19 | Grindheimsvatnet (Agder, Norway) | |
| Tetraedron sp. | | 1991-05-23 | 1991-05-23 | Svartaholtjørnet (Vestland, Norway) | |
| Tetraedron minimum | | 1990-09-28 | 1990-09-28 | Vikerauntjønna (Trøndelag, Norway) | |
| Tetraedron minimum | | 1990-09-28 | 1990-09-28 | Vikerauntjønna (Trøndelag, Norway) | |
| Tetraedron minimum | | 1989-09-19 | 1989-09-19 | Vikerauntjønna (Trøndelag, Norway) | |
| Tetraedron sp. | | 1991-10-14 | 1991-10-14 | Stavsjø (Innlandet, Norway) | |
| Tetraedron minimum | | 1991-09-07 | 1991-09-07 | Dælivannet (Akershus, Norway) | |
| Tetraedron minimum | | 1989-09-07 | 1989-09-07 | Dælivannet (Akershus, Norway) | |
| Tetraedron sp. | | 1991-06-03 | 1991-06-03 | Kolbotnvannet (Akershus, Norway) | |
| Tetraedron minimum | | 1989-09-22 | 1989-09-22 | Haukvatnet (Trøndelag, Norway) | |
| Tetraedron cf. incus | | 1991-06-14 | 1991-06-14 | Rørvatnet (Møre og Romsdal, Norway) | |
| Tetraedron sp. | | 1991-06-10 | 1991-06-10 | Kjemsjøen (Innlandet, Norway) | |
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