Marmorkrebs distribution in Japan modeled using P. fallax. Potential distribution of Marmorkrebs in Japan as predicted by a model trained using native P. fallax distribution in United States. Legend in this and subsequent figures: Gray scale indicates similarity between known and predicted habitats (i.e., habitat suitability). Circles show presence of Cambaroides japonicus (see Table 3); square shows location of single Marmorkrebs found in Sapporo in 2006 . Regions with red hatching in this and subsequent figures show areas with novel conditions compared to the training dataset according to multivariate environmental similarity surfaces (MESS) analysis. Inset in this and subsequent figures: Choropleth map of rice production of agricultural regions .