Butterflies are probably the largest invertebrate herbivore group wiht representative data on hostplant associations.
Global compilations
These are mostly compilation of references in the literature
HOSTS - a Database of the World's Lepidopteran Hostplants, provided by the Natural History Museum of London, contains records for most lepidopteran families, including all butterfly families. Last update 18 Aug.2010
Lepidoptera and other life forms
Local, study sites databases
These are mostly based on (standardized) field observations in study sites
Catterpillars