Four phenotypically and phylogenetically distinct lineages in Phytophthora lateralis

► We reveal four evolutionary lineages in the destructive pathogen Phytophthora lateralis. ► Two are confined to Taiwan, one to the UK, and one to North America and Western Europe. ► The lineages are phenotypically distinct and hence differently adapted. ► The lineages represent discrete phylogenetic units. ► They pose challenging questions about the pathogen's origins and spread.