Entomological Investigation of the Main Entomatic Adversities for Terrestrial Gastropods Helix aspersa Müller (Mollusca Gastropoda Pulmonata): A Preliminary Study in Sardinian Heliciculture Farms

Simple Summary Beetles that predate on the Helix aspersa Müller species represent a serious problem for snail farms, causing serious damage, and progressively lead to a reduction in the snail population. Entomological control in snail farms is of fundamental importance to avoid massive colonization that could lead to their death. The greatest difficulty in finding effective solutions to combat predators is that of not being able to use chemicals, given that they would damage the health of the snails. In this study, all the variables that may be considered to avoid an increase in predators were considered and are discussed. Abstract In the years 2020–2022, a survey was carried out with the aim of controlling the entomofauna present in seven Sardinian snail farms. The sampling was carried out during the spring–summer and autumn–winter periods, corresponding to the production cycles of the Helix aspersa snails (Müller, 1774), the species most frequently bred in snail farms. The samples were taken from farms located in different areas of the region. For the predatory species found in most of the farms, 38% of the individuals were of the Silpha tristis Illiger, 1798 (Coleoptera: Silphidae) species, 32% were Ocypus olens Müller, 1764 (Coleoptera: Staphylinidae), and 24% were Carabus (Macrothorax) morbillosus constantinus Kraatz, 1899 (Coleoptera: Carabidae). The Lampyris sardiniae Geisthardt, 1987 (Coleoptera: Lampyridae) and Licinus punctatulus Fabricius, 1792 (Coleoptera: Carabidae) species were equally detected in 3% of the farms. In some farms, the predatory species S. tristis and C. morbillosus costantinus had caused the death of several snails. This preliminary study aimed to provide a first evaluation and description of the critical issues facing the snails present in seven Sardinian snail farms. First, a specific survey of the entomofauna during two observational periods (i.e., the spring–summer and autumn–winter periods) was conducted. Context-specific description and evaluation will allow providing valid information for Italian and European heliciculture farms to ensure the well-being of the mollusks. The presence of predatory species in snail farms is not easy to control, but some precautions could be useful to avoid massive colonization.

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