My practices are as such that I tend to brumate the more "northern range" zonata at slightly cooler temps (multicincta, zonata zonata, Cascade intergrades, etc...), which translates to around 45F.......the more south we go, the slightly warmer I place them, so agalma will brumate for me at 50-55F and produce with great success. I wouldnt say that Coastals or pulchra come from "hotter/dryer" climates per se, as all zonata come from a range of areas in their respective mountain ranges -- from high elevations where it's dryer/cooler to riparian/Transition Life zones where it's wetter/warme, respectively, as we must remember that up in the mountains the temperatures and air quality vary greatly as opposed to lower elevations in which people tend to be more familiar with.
I think, for me anyway, this is where the importance of locality comes into play. No two zonata populations are one in the same, however we do what we can without that important information and create a make-shift generalized microhabitat as best we can. But there are options. Frank Retes, et al, often comments on such notions and with good purpose, as it's important to consider, indeed, how we support what species/populations/etc requires what kind of support for optimal captive success.
Broad topic, short on time.....meeting in 12 minutes.......talk more later...... 
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Jerry Kruse
www.zonatas.com
And God said, "Let there be zonata subspecies for all to ponder..."