Distribution of Myrmecophilus acervorum (Panzer, 1799) (Orthoptera: Myrmecophilidae) in Poland

This study summarises information on the occurrence of Myrmecophilus acervorum in Poland in the years 1851–2022. We collected information about 143 localities: 40 from literature and 103 unpublished. Myrmecophilus acervorum is reported from seven new regions: the Baltic Coast, Białowieża Primeval Forest, Eastern Sudety Mts, Kraków-Wieluń Upland, Podlasie Lowland, Sandomierska Lowland and Trzebnickie Hills. While until 2010 observations were rare (35 localities), in the years 2011–2022 the species was found in 108 new localities. A total of 443 individuals of M. acervorum were observed in Poland, but the sex was identified only for 138, of which 135 were mature females or female nymphs. Males were recorded only historically in the Pomeranian Lakeland. At present, these records should be treated with caution, as they are uncertain.