RMRS-RN-11WWW: Hosts and Geographic Distribution of Arceuthobium oxycedr


Trees and woody shrubs of the genus Juniperus form pure or nearly pure forests over extensive areas of northern Africa, Mediterranean Europe, the Near East, central Asia, the Indian subcontinent, and western China. They typically occur in arid regions where growth is slow. The future health and existence of many juniper forests is threatened by excessive human use, grazing by domestic livestock, insects, and diseases.

One of the major disease agents of Old World junipers and other Cupressaceae is the juniper dwarf mistletoe, Arceuthobium oxycedri (DC.) M. Bieb. (Figure 1). Arceuthobium oxycedri is the type species of the genus and one of three Old World dwarf mistletoes that parasitize Juniperus spp. and other Cupressaceae (Hawksworth and Wiens 1976, 1996). Arceuthobium oxycedri also has the most extensive geographic distribution of the 42 recognized species of Arceuthobium. Its range extends over 100º of longitude or about 10,000 km from Spain and Morocco to western China.

In their updated monograph on Arceuthobium, Hawksworth and Wiens (1996) describe their frustrations in summarizing available records for the hosts and distribution of A. oxycedri. The labels on many early collections are scarcely legible and in unfamiliar languages. The political geography of Europe, northern Africa, the Near East and central Asia has changed significantly, resulting in changes in national borders and place names, since A. oxycedri was first described in 1819.

Therefore, many collection sites are difficult, if not impossible, to locate on present day maps. In addition, new information on relationships in Juniperus has led to taxonomic revisions. Consequently, the Hawksworth and Wiens (1996) summary of this important Old World mistletoe is much outdated.

We review here information on the hosts and geographic distribution of A. oxycedri based on literature, collections, and new species definitions for the junipers. Hosts and geographic information are organized by region:

We plan to update this information periodically and welcome additional information from colleagues knowledgeable of the distribution and hosts of Arceuthobium oxycedri for inclusion in future versions of this paper.

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Title: RMRS-RN-11WWW: Introduction
Electronic Publish Date: September 2001
Last Update:
August 20, 2008