Update on the situation of Garella musculana in Italy
A recent study has been conducted in Italy to assess the current distribution of Garella musculana (Lepidoptera: Nolidae – EPPO A2 List) following its first detection in 2021 in Veneto region (EPPO RS 2022/034). In 2022, walnut (Juglans spp.) trees growing in orchards, hedgerows, or private gardens were surveyed. Plants were visually inspected for signs of presence of G. musculana in 151 sites, most of them located in Veneto region (120), but also in Lombardia (9), Friuli-Venezia Giulia (2) and Emilia Romagna (20). Insect identity was determined morphologically, and for larvae the identification was confirmed by molecular tests. In addition to field surveys, data mining studies were conducted using available sources (e.g. literature, databases, web fora). G. musculana was found (or signs of presence observed) in 79 sites (out of the 151 surveyed), mainly in Veneto region (pest found in 70 sites), with some records in Emilia Romagna (9 – only based on signs of presence). G. musculana was not recorded in Lombardia or Friuli-Venezia Giulia regions. Data mining identified a single record (posted on a web forum) of an adult specimen collected in a private garden in Padova province (Veneto region). During these studies, the insect was mainly collected from Juglans regia and to a lesser extent from J. nigra. It was not recorded on nearby poplar or almond trees. G. musculana was mainly found in walnut orchards (87.3%), and to a lesser extent in hedgerows (10.2%) and private gardens (2.5%). The authors concluded that G. musculana should be considered as established in North-Eastern Italy, and that further studies are needed to better understand its biology and impact on cultivated walnut trees in Italy.
Sources
Zanolli P, Scaccini D, Pozzebon A (2023) New insights into the distribution and spreading of the Asian walnut moth, Garella musculana (Erschov, 1874) (Lepidoptera, Nolidae) in Europe with a focus on the Italian range. Biodiversity Data Journal 11, e107609. https://doi.org/10.3897/BDJ.11.e107609