A teratological specimen of Acerentomon gallicum Ionesco, 1933 having additional rudiments of abdominal appendages on segments IV and V is described. The hypothesis concerning the origin of seta P3 in the sternal chaetotaxy is discussed.
A. Szeptycki, Department of Invertebrates, Institute of Systematics and Evolution of Animals of the Polish Academy of Sciences, Slawkowska 17, 31-016 Krakow, Poland, e-mail: szeptycki@isez.pan.krakow.pl