Abstract
The pine bast scale, Matsucoccus matsumurae (Kuwana) native to Japan, attacks seven related Pinus species (all members of the subsection Sylvestres) in Asia and North America. In Japan the scale occurs on two native pines which extend from the northern edge of Honshu (41°30′N) to Yaku Shima (30°15′N). In the United States, the exotic scale M. resinosae Bean and Godwin (= M. matsumurae?) is a destructive pest of P. resinosa, the only native member of the Sylvestres group. High overwintering mortality north of 41°15′N latitude and the absence of suitable hosts south of 40°N latitude have inhibited the northern and southern spread, respectively, of this scale in North America. In China, M. matsumurae is a serious introduced pest of two native pines, P. tabulaeformis and P. massoniana, whose latitudinal ranges extend well beyond the current northern (41°15′N) and southern (30°15′N) limits of scale distribution. The scale is held within these latitudinal limits by high winter (>96%) and summer (70–90%) mortality to the north and south, respectively. M. matsumurae is adapted to the specific climatic regimes of its natural range in southern Japan, the latitudinal limits of which match perfectly its exotic ranges in China and the United States. With only a brief evolutionary history (40 years) in these two countries, the scale is still very much on an island, confined by its inability to exploit available hosts in areas with more extreme winter and summer temperatures than its native island habitat.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have