By name or number, identify all of the following five choices that are NOT arthropods: trilobites, chelicerates (read as: ki-LI-keh-rah-tehs), crustaceans, icterids (read as: ik-TEHR-ids), polyplacophores (read as: poh-lee-PLAH-koh-fors).
ICTERIDS AND POLYPLACOPHORES (ACCEPT: 4 AND 5)