Weitere Beiträge zur Kenntnis der Fichtenröhrenlaus Elatobium abietinum (Walk.) unter besonderer Berücksichtigung ihrer Weltverbreitung1

Abstract

SummaryBasing on a study of all synonyms and prior classifications we find the valid name of the Green Spruce Aphid is Elatobium abietinum (Walker 1848). In Europe there exists only one Elatobium, the existence of E. indecisa (Walker 1849) sensu Börner could not be proved. The E. momii (Shinji) we find to be a real species but the E. piceana (Inouye) is closely related to our european species, we named it E. abietinum forma piceana. A comparative taxonomic analysis shows this relation and demonstrates the north‐american specimen beeing more similar to european than to eastasiatic forms.By intensive studies of the literature, world‐wide correspondences with entomologists and wide‐spread own collections throughout West‐Europe and parts of Northamerica we got a good survey of the distribution of E. abietinum over the world. We discuss following factors conditioning abundance: the susceptibility of certain hostplants together with the ability to partial anholocyclic overwintering (paracyclus) in connection with climatic conditions.The hypothesis is stated E. abietinum to be primarily imported from Europe to Northamerica, where it has settled down at first in the pacific coastal regions. Since there are connections between the sitca‐spruce area and the transcontinental spruce belt (which includes some preference hosts) E. abietinum is presumed to become a possible dangerous forest pest for wider parts of Northamerica.