Florida, Georgia, and Texas are the only previous records for the mainly Neotropical shield bug Symphylus caribbeanus Kirkaldy in the United States. The record for Georgia, however, is based on a misidentification of Stethaulax marmoratus (Say). The first valid record for Georgia and first record for South Carolina extend the distribution of Sy. caribbeanus based on recent collecting; new state records based on museum specimens are Alabama, Mississippi and North Carolina. Nymphs and adults were observed in South Carolina on fruits of yaupon (Ilex vomitoria; Aquifoliaceae) and in Florida on fruits of Brazilian peppertree (Schinus terebinthifolius; Anacardiaceae); an adult was taken in Georgia on fruits of wax myrtle (Morella cerifera; Myricaceae). Most previously recorded plant associations might not be true hosts that support nymphal development. Although the relatively late report of Sy. caribbeanus from the United States (1914 in Florida) suggests an adventive status, this scutellerid might be a native, but long unrecognized species of the Floridian fauna. The later report from southern Texas (1977) might represent range expansion from northern Mexico. Images of nymphs (instars IV, V) and adults of the color morphs observed in South Carolina are presented.