In this study, molecular and morphological analysis of Palmicultor Williams, 1963 (Hemiptera: Coccomorpha: Pseudococcidae) mealybugs, intercepted on plant material entering California and collected in Florida, provides evidence for the existence of a cryptic species under the taxon currently known as P. palmarum (Ehrhorn, 1916). A characterization and analysis based on three molecular markers (mitochondrial COI 5′ end and COI 3′ end regions and nuclear rRNA 18S) for all four described species and the putative cryptic species is presented. Morphological characters used to diagnose species of Palmicultor are evaluated, and an updated identification key to adult females is presented. The history of interceptions of invasive species of Palmicultor in California is addressed, and new host plant records are reported. Considering the high intraspecific morphological variability within the genus, the molecular markers sequenced here provide a useful tool to confirm species identity during high-risk interceptions of these mealybugs.