Karyotypes of four species of Pachypsyllinae were reinvestigated (Pachypsylla celtidismamma, P. celtidisvesiculum, P. venusta, Pachypsylla sp. 2, and Tetragonocephala flava) in order to interpret contradiction in the literature data. The morphology of testicular follicles for three species was described for the first time.
A. Maryanska-Nadachowska, Department of Experimental Zoology, Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, Slawkowska 17, 30-016 Krakow, Poland