Distribution of Toumeyella parvicornis (Cockerell) nine year after its introduction in Campania Region, Italy

The pine tortoise scale Toumeyella parvicornis (Cockerell) (Hemiptera: Coccidae) is considered a major threat for pine species in Italy. Strong phytosanitary measures have been adopted by the Ministerial Decree of 3 June 2021 with the aim to contain the spread of this harmful pest in the country. Native from the Nearctic region, T. parvicornis has been recorded in Campania during 2014 infesting mainly Italian stone pine (Pinus pinea) in the province of Naples. In following years, the pine tortoise scale has been reported in different Italian regions (Abruzzo, Lazio, Puglia and Tuscany) and in 2021 a first outbreak has been recorded for France. The Plant Protection Organization of Campania region suggested the application of the first containment measures in two executive decrees in 2015 that were updated in 2021. Among different pine species P. pinea resulted to be the most susceptible host with huge infestations and high mortality rate interesting mainly pines already weakened by environmental and anthropic factors. In less than a decade T. parvicornis spread over a great part of the region, from urban areas to forest plantations by means of wind dispersal of crawlers or favored by their passive transport with vehicles. The phytosanitary surveys carried out in Campania since 2015 to 28.02.2023, reported in the database SIMFito, list as monitored 328 of 550 municipalities. 28% of the 2700 surveyed sites resulted infested. To date T. parvicornis is infesting pines in 203 municipalities of the region located along the coastal areas from northern regional limit to the gulf of Policastro to the south. The species is largely present also in the internal zones of the Avellino, Benevento and Caserta provinces. The elevation of infested areas ranges from 2 m of coastal plains to 840 m a.s.l. of hilly zones. The main infestations have been observed on Italian stone pine and Maritime pines (P. pinaster), with clear prevalence of the first species (95%). Aleppo pine (P. halepensis) infestations resulted usually inconsistent. The first serious attacks on Austrian pine (Pinus nigra) have been observed in November 2022 at Avellino. The spatial analysis on the progress of the infestations by T. parvicornis showed a spread rate of 7 km/year heading north, 8 km/years eastwards and 15 km/year southwards with new territorial records located along the main regional road network.