Genus: Tetraedron
| Site | Municipality (county) | Num. obs. | Num. species | Num. images | Last obs. | |
|---|
| Dælivannet | Akershus, Norway | 2 | 1 | 0 | 1991-09-07 | |
| Grindheimsvatnet | Agder, Norway | 1 | 1 | 0 | 1989-09-19 | |
| Haukvatnet | Trøndelag, Norway | 1 | 1 | 0 | 1989-09-22 | |
| Kjemsjøen | Innlandet, Norway | 1 | 1 | 0 | 1991-06-10 | |
| Kolbotnvannet | Akershus, Norway | 1 | 1 | 0 | 1991-06-03 | |
| Rørvatnet | Møre og Romsdal, Norway | 1 | 1 | 0 | 1991-06-14 | |
| Stavsjø | Innlandet, Norway | 1 | 1 | 0 | 1991-10-14 | |
| Svartaholtjørnet | Vestland, Norway | 1 | 1 | 0 | 1991-05-23 | |
| Tretjønnet | Agder, Norway | 1 | 1 | 0 | 1990-06-26 | |
| Vikerauntjønna | Trøndelag, Norway | 3 | 1 | 0 | 1990-09-28 | |
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