Unaspis citri occurs in São Miguel island, Azores (Portugal)
Unaspis citri (EPPO A1 quarantine pest) was recorded for the first time in the island of São Miguel, Azores (Portugal) in the 1920s and caused at that time serious damage to citrus. In PQR (EPPO database on quarantine pests), U. citri was considered as 'found in the past but not established' in the Azores, as no further information was given since this old report. However, a recent publication indicates that this is not the case and that U. citri is established in the island of São Miguel. It is reported that Lepidosaphes beckii and Unaspis citri are the most abundant armoured scale species in citrus orchards (representing 80 % of the total frequency of Homoptera, Coccoidea) and that chemical treatments are applied regularly. Studies have also showed that Encarsia citrina contributes considerably to the biological control of Lepidosaphes beckii and Unaspis citri.
Soares; A.O.; Elias, R.B.; Schanderl, H. (1997) Encarsia citrina (Crawford) (Hymenoptera, Aphelinidae) a parasitoid of Unaspis citri (Comstock) and Lepidosaphes beckii (Newman) (Homoptera, Diaspididae) in citrus orchards of São Miguel island (Azores).
Boletin de Sanidad Vegetal. Plagas, 23(3), 449-456.