This interactive identification key can be used to identify 155 armored scale insect species from the tribe Aspidiotini (Hemiptera: Diaspididae). This tribe includes several polyphagous and specialist pests that are commonly encountered at ports of entry to the United States and many other countries. The included species are recognized as minor to major pests or are considered to be potential emergent pests. Many of the species included are widely distributed and the tool is intended to be applicable toward an international audience. However, the list is based largely upon quarantine interceptions from the United States.