Typification and distribution of two hybrids of Juniperus communis L.

Abstract

The common juniper (Juniperus communis L.) is a widely distributed species in the northern hemisphere, with numerous infraspecific taxa proposed over time. Eight groups are currently recognized, three of them occurring in Europe and the Mediterranean; they are considered as species, subspecies or varieties, with the country of origin of the taxonomists having a strong influence on this decision. Introgressions and hybrids have been recognized among some of these infraspecific taxa. This paper typifies two known hybrids between Eurasian varieties of J. communis, and discusses several confusing names proposed in this group, related with these nothovarieties. Juniperus communis nothovar. intermedia is a hybrid between J. communis var. communis and J. communis var. saxatilis, widely distributed in Europe, but sometimes ignored or confused with other taxa; several names applied to infraspecific taxa of this group actually seem to refer to this hybrid. It was described in 1851, but there is no known type; a neotype is proposed in this paper. A hybrid between J. communis var. hemisphaerica and J. communis var. saxatilis was reported in 2020, but not properly described; it is done in this paper.