First record of whitefly quarantine species Aleurocanthus spiniferus Quaintance, 1903 (Hemiptera: Aleyrodidae) in Croatia

Vrsta štitastog moljca Aleurocanthus spiniferus Quaintance, 1903 (Hemiptera: Aleyrodidae) podrijetlom je iz jugoistočne Azije, otkuda se proširila u tropska i suptropska područja Azije, u Afriku te u područje Pacifika. Polifagan je štetnik kojemu su najvažniji domaćini biljke iz rodova Citrus, Pyres i Vitis. Štete na biljkama čine ličinke i odrasli razvojni stadiji štetnika sisanjem biljnih sokova na naličju listova te izlučivanjem obilne medne rose, na koju se sekundarno naseljavaju gljivice čađavice. Ta je karantenska vrsta u Europi prvi put nađena 2008. godine u nasadima agruma na jugu Italije, u provinciji Lecce (Porcelli, 2008). Nakon prvog nalaza u Italiji, vrsta je prebačena s EPPO A1 na EPPO A2 listu, a u Hrvatsko je sukladno EU direktivi 2000/29/EC, taj štetnik svrstan na Popis II Dio A Odjeljak I Pravilnika o mjerama za sprječavanje unošenja i širenja organizama štetnih za bilje, biljne proizvode i druge nadzirane predmete i mjerama suzbijanja tih organizama (NN 74/06). U Hrvatskoj, vrsta A. spiniferus nađena je prvi put 30. svibnja 2012. na ukrasnim sadnicama naranče (Citrus aurantium L.) iz vlastitog uzgoja, u jednom vrtnom centre u Splitu (42°30\u2729\u27\u27N, 16°26\u2740"E; UTM 33T XJ 1919).Orange spiny whitefly, Aleurocanthus spiniferus Quaintance, 1903 originated in south-east Asia and has spread widely in tropical and subtropical Asia, and into Africa and the Pacific. Citrus spp. are the main hosts of economic importance, but A. spiniferus has been recorded from woody hosts of 13 plant families. This species is listed as a quarantine threat to Europe and is included in the EU Annex IUA1 and in the EPPO A2 list. In Europe, it was reported for the first time in Italy, in 2008. In May 2012, A. spiniferus was first found in Croatia, on ornamental potted orange seedlings (Citrus x aurantium L) from domestic production in one nursery garden in Split. Infested orange plants have locally numerous small, brownish to black scales with a short fringe of white wax on the underside of leaves. The identification of the whitefly species was carried out by the Institute\u27s Laboratory for Zoology and the result was confirmed in Plant Protection Service, Wageningen, The Netherlands. The origin of the infestation of this alien species is still unknown, but it is assumed that the infection originated from imported plant material from Italy. A. spiniferus causes general weakening of seriously infested plants due to sap loss and the growth of sooty mould. Dense colonies of whitefly immature stages develop on leaf undersides, whereas the adults fly actively when disturbed. Leaves and citrus fruits have spots of sticky, transparent honeydew, which become covered in black sooty mould fungus. A heavy infestation gives trees an almost completely black appearance. The potential host range of A. spiniferus in the EPPO region would be essentially citrus, with some possibility of establishment on other woody plantation crops growing in the southern part of the region in climatic conditions suitable for the pest. It presents a potential permanent risk to citrus in Croatia, especially to production of mandarin in Neretva river valley. For now, A. spiniferus has status of eradicated species in Croatia