Range and Elevational Shifts of Mistletoes Under Future Climate Change Scenarios

Climate change is reshaping species' geographic distributions, with range shifts to higher elevations and latitudes. Parasitic plants like keystone mistletoes are particularly vulnerable to climate change because of their obligate dependence on host plants. Here we investigated how climate change under both optimistic and pessimistic scenarios will alter the distribution of suitable habitat of 10 Psittacanthus mistletoe species in Mesoamerica by 2050-2090. We assessed whether species with narrow habitat, geographic distribution, and host range face greater risks than generalist, widespread species. Suitable habitat for most temperate high-elevation species shifted upward in elevation under most pessimistic climate scenarios, accompanied by significant range size reductions. These findings underscore the importance of evaluating climate change impacts on mistletoe distributions across diverse environments and biogeographical regions, as well as their ecological interactions with host plants and mutualists (pollinators and seed dispersers) to inform effective conservation strategies.