Altogether 43 705 species are so far found in Norway, of which 65 % belong in the animal kingdom. The largest taxonomic group is insects, of which there are more than 18 000 species. Presumably there are still many species yet to be found, and the total number of species thought to exist is estimated to approximately 60 000.
In 2015 the Norwegian Biodiversity Information Centre initiated a study to evaluate the state of our knowledge concerning the number of known and unknown species present in Norway, and also with respect to knowledge of taxonomy, dispersal and ecology of species. The work was led by the Natural History Museum at the University in Oslo. Altogether 1920 taxonomic groups were examined, covering 97,5 % of the known species diversity in the country.
The number of documented species from Norway is 43 705, that is: 28 417 animals 8418 fungi and 4458 plants. These are the three kingdoms with the highest species numbers. There are also 1105 species of Chromista, 553 species of Protozoa, 479 Alveolata and 275 Amoebozoa.
We don't have enough knowledge about several taxonomic groups. It is to expect that kingdoms like Amoebozoa and Chromista have a high number of specie still unknown to us. The numbers presented over is therefore minimum numbers..
The largest taxonomic group is Arthropoda that includes not less than 22 695 documented species, of which 18 287 are insects. Diptera and Hymenoptera are the two largest insect groups, each of them with more than 5000 species in Norway.
Chironomidae and Mycetophilidae are examples of two large groups of Diptera, with 625 and 611 species respectivly. Within Hymenoptera the largest group is Apocrita with 4494 species. This number includes 288 are bee species, of which 35 are bumblebees.
Other groups with a high number of species are Chordata (1000 species) and Mollusca (947 species). The majority of Chordata species are Vertebrata, while most Mollusca are Gastropoda.