All cultivars of carambolas (Averrhoa carambola L.) grown in Florida are considered hosts of the Caribbean fruit fly [Anastrepha suspensa (Loew)] (Norrbom & Kim 1988). Fruits must be disinfested with cold, irradiation, or heat before they can be exported to nations having quarantine requirements. These treatments increase the cost of fruits and may decrease fruit quality. Resistant carambola cultivars have not been employed as a means for reducing losses to the pest by growers. Relaxation or elimination of postharvest quarantine treatment requirements may be possible for resistant cultivars. Howard & Kenney (1987) determined that 'Golden Star' was less susceptible to Caribbean fruit fly than 'Arkin' or 'Fwang Tung' based on the numbers of eggs oviposited in harvested fruits. They ran their tests in cages using colony-reared flies and also found fewer and lower weights of pupae developing from 'Golden Star' fruits than from fruits of the other cultivars. The present experiments were designed to identify antibiosis to Caribbean fruit fly eggs and larvae in some Florida carambola cultivar clones and seedlings from open pollinations or controlled crosses between various clones. Antibiosis (after Kogan & Ortman 1978) is due to fruit properties that adversely affect the metabolism of the growing fruit flies. Carambolas used in the experiments were from non-commercial research groves at the Miami National Clonal Germplasm Repository of the Subtropical Horticulture Research Station. Seedlings were derived from crosses described by Knight (1982) and Schnell & Knight (1989). Tree management included irrigation, fertilization, pruning, and mechanical and chemical weed control, but no insecticide application. Fruits were harvested between 16 December 1993 and 20 January 1994 as they became available. Five clones and 11 seedlings described in Table 1 were bioassayed. A treatment consisted of one tree (cultivar or seedling) from one harvest date. For most clones and seedlings, only a single tree existed, therefore variability among trees was not assessed. 'Arkin' and 'Fwang Tung' were each bioassayed on two dates so effect of sam-