Thorsellia bacteria have now been found in mosquito species that are the major vectors of malaria in Africa, Asia and South America.

[5] However, T. anophelis has also been found in the reproductive tissues of male and female Anopheles gambiae and An.

[6] Currently, little is known about Thorselliaceae in nature apart from that it has been shown in several studies that Thorsellia anophelis dominate the malaria mosquito gut flora and their breeding waters.

[5][7][8] Thorsellia has besides in Anopheles also been found to dominate the gut flora in the mosquito species Culex tarsalis,[9][10] which is a vector of among other things, West Nile virus and encephalitis.

[11] Coetzeea (named after the South African mosquito researcher Maureen Coetzee) has so far only been found in Brazilian Anopheles darlingi.