Patroon en snelheid van de kolonisatie van Nederland door de Kleine roodoogjuffer (Erythromma viridulum)

R. Ketelaar, 2006. Pattern and rapidity of the colonisation of Erythromma viridulum in The Netherlands. Brachytron 9(1&2): 33-37. Erythromma viridulum is one of the southern Odonata quickly colonising large parts of Europe. The species was a very rare damselfly in The Netherlands until 1970. After 1980 it rapidly colonised The Netherlands and has become one of the most common species. It is suggested in this article that the expansion of Erythromma viridulum took place via three routes: an expansion northwards from Belgium, an expansion north-westwards via the Rhine valley and a possible expansion from an outpost in the north of The Netherlands. The first two routes can be tested by a close examination of German and Belgian records; the latter will probably remain suggestive.