5 species in 4 genera are known from Block Island. Caterpillars in this family are generally vivid green and slug-like. Adults of most Nearctic species are brown, some with green patches, and are small to medium in size with a stout appearance. The local fauna of this family is briefly discussed on the post for the superfamily; refer to my 2021 paper on the Zygaenoidea of Block Island for more detail.
Hunt, A.S., 2021. Moths of Block Island (Rhode Island, USA) I: Zygaenoidea. Northeastern Naturalist 28(4): 497–510.