Is Dichogaster bolaui (Michaelsen, 1891) the first domicole earthworm species?

The term domicole, derived from the Latin domus (house) and colere (to inhabit), applies to species that are able (or adapted) to live in urban dwellings. Examples of domicole species include, for example, Psocoptera (dust lice) and Arachnida (spiders). However, so far, no earthworm species has been described as being capable of adapting to this type of niche. It seems, however, that the tropical species Dichogaster bolaui (Michaelsen, 1891) might be the first earthworm species to be defined as a domicole species. D. bolaui is native to eastern Africa. However, it has a wide distribution in tropical and subtropical regions. Additionally, it has been recorded in greenhouses in temperate countries and has also been observed in bathtubs and toilet bowls in Finland and Sweden. We collected data regarding the abundant presence of this species in bathtubs, showers, and sewer pipes in a student dormitory in Szombathely, Hungary, and in a private house in Haifa, Israel. Our data suggest that D. bolaui independently colonized the sewerage systems several times and established breeding populations and, therefore, has become a domicole.