Abstract
The specificity of the specialisation of Phengaris Doherty, 1891 caterpillars to their host ants is still not fully understood. In this report, we summarize all available records of Phengaris in ant nests from the Czech Republic.
P. alcon (Denis & Schiffermuller, 1775) was found exclusively in nests of Myrmica scabrinodis Nylander, 1846 at four sites, and one P. nausithous (Bergsträsser, 1779) caterpillar was found in a nest of M. scabrinodis. According to published records, P. nausithous may use M. scabrinodis at the edges of its range but should be adapted exclusively to M. rubra (Linnaeus, 1758) in the centre of its range.
No records of P. arion (Linnaeus, 1758), P. teleius (Bergsträsser, 1779) and P. alcon populations feeding on Gentiana cruciata (Gentianaceae) ("P. rebeli") are available from the Czech Republic.