EN
New distributional data for 14 longhorn beetle species is presented, of which 6 taxa are recorded from the city of Warsaw for the first time whilst new localities for 12 species are given. Some are considered rare across Mazovian Lowland or the whole range: Axinopalpis gracilis, Cerambyx cerdo, Clytus lama, Chlorophorus herbstii, Grammoptera ustulata, Leioderes kollari, Necydalis major, Rhagium sycophanta, Xylotrechus ibex. New locality of C. cerdo and at the same time a second place of development of this endangered species in Mazovia is given for the first time. So far, the only known locality of the great capricorn beetle in Bielański Forest nature reserve overgrows with undergrowth. Even though it remains a Nature 2000 site, no protective activities are being conducted to preserve this unique species. To conclude, this special protection area continuously annihilates centuries-old oak stand – remains of former Mazovian Primeval Forest and shrinking population of C. cerdo – its major object of protection and special care. Rare L. kollari spreads its range across central Poland and is being found mainly as larval galleries. Similarily A. gracilis is spreading its range towards northern part of the country. Quercus rubra L. is given as a new host plant of Pyrrhidium sanguineum whereas N. major is recorded from Padus avium Mill. for the first time. Interestingly, C. lama turns out to be prefering Larix decidua Mill. on its main locality in Warsaw – Kabacki Forest nature reserve. Occurrence of elusive R. sycophanta in Natolin Forest reserve is confirmed whereas second locality of rare X. ibex is given. New abberation of Clytus arietis L. natolini ab. nov. is described..