Answer: I have checked several veterinary poisonous plants databases such as the one from Cornell University
and did not find this plant listed as a problem plant.
The ASPCA Animal Poison Control Center lists a calathea on its non-toxic plants list so although I would not of course encourage the cats to eat houseplants it appears this is not one to worry about in particular. The url for that list is
http://www.vspn.org/Library/misc/VSPN_M01236.htm in case you'd like to review it.
Enjoy your new plant.
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