Mravenci (Hymenoptera: Formicidae) Nymburska

Abstract: The ant fauna of the Nymbursko region (Central Bohemia, Czech Republic) was studied intensively between April 2020 and September 2023. We also used our older data, gathered from 1985 onwards. Ants were collected from 92 localities spread throughout the studied region, from which 53 ant species are known, i.e. 58.9% of ca 90 species known to occur in Bohemia. The most interesting localities are solitary marlstone hills (called buttes in geomorphology), remnants of the Mesozoic sea bottom. Their steep southern slopes are covered by sparse xerothermic vegetation, and on their northern slopes are mixed forests. There are nine such hills protruding ca 20–60 m above the surrounding landscape and we found there altogether 42 ant species. Some of them, Temnothorax interruptus (Schenck, 1852), Tapinoma erraticum (Latreille, 1798) and Plagiolepis pygmaea (Latreille, 1798) were found only there. Another interesting locality is the former military training area of Milovice, which is covered by steppe vegetation and where 30 species of ant were recorded, including Lasius carniolicus Mayr, 1861 known in the Czech Republic only from this place. Other species that are only rarely found in Bohemia include the social parasite Anergates atratulus (Schenck, 1852) which we found in a nest of Tetramorium caespitum (Linnaeus, 1758). In particular, we searched for the thermophilic arboreal ant Colobopsis truncata (Spinola, 1808) which was until recently considered to be a very rare species in Bohemia. We found it in 26 localities and we suppose that it is spreading in Central Bohemia, most probably due to climate change. Relatively rare species also include Myrmica curvithorax Bondroit, 1920 and Lasius jensi Seifert, 1982. The question of whether Camponotus aethiops (Latreille, 1798), supposedly present during the 1980s, still exists at the site remains open. We conclude that the ant fauna of the Nymbursko region is relatively rich, above all owing to the presence of several unique marlstone hills and one steppe locality.

Key words: Faunistics, Ants, Hymenoptera, Formicidae, Bohemia, Czech Republic