Literatural records about true water beetles (sensu JÄCH 1998) of the Middle-Eastern Poland were compiled and critically analysed. 241 species have been recorded so far. Two further species were given basing on false determination (Helophorus micans, Limnebius stagnalis). Species recorded in particular faunistic regions were listed. The fauna of the analysed area was discussed according to its geographical diversity, habitat differentiation and the conservation of endangered habitats. The importance of this area for the protection of beetle species and assemblages was emphasized.
The paper presents new records of some species of Hydrophiloidea from Poland. There is also a correction of misdetermination of the specimen Helophorus (Eutrichelophorus) micans FALD. recorded mistakenly from Poland. An updated checklist of Polish Hydrophiloidea is given.
Paper presents new data about the occurrence of 7 species of the superfamily Hydrophiloidea and the family Hydraenidae, rare in Poland. Berosus (Berosus) signaticollis (CHARP.) is reported for the first time from the Western Sudetes.
Genetic variability of three sympatric crucian carp (Carassius carassius) populations from NW Poland was studied within a research project aimed at assessing the utility of those populations for stocking in inland waters. DNA samples were collected from 65 individuals. Restriction analysis was performed using 4 enzymes (HaeIII, HinfI, FspBI, TasI) of known restriction sites. The restriction profiles obtained were classi fied as belonging to a single haplotype (H-1). Selected DNA products were sequenced; the subsequent comparison made it possible to detect the presence of substitutions in the genome fragment analysed.