A chromosomal analysis of the West European species of Aphodius Illiger, Subgenus Aphodius S. Str. (Coleoptera: Aphodiidae)

Abstract

The karyotypes of the five West European species of Aphodius (A. str.) are described and illustrated. All have 9 pairs of autosomes plus Xy sex chromosomes. Two species, A. fimetarius (Linnaeus) and A. foetidus (Herbst) have long heterochromatic blocks on some chromosomes, while the other three species, A. conjugatus (Panzer), A. foetens (Fabricius), and A. pedellus (DeGeer) lack these segments. A. pedellus may have one or two B-chromosomes, while some southern populations of A. foetidus may have up to six B-chromosomes. It is suggested that the occurrence of B-chromosomes is the probably explanation of the differing chromosome numbers recorded by Yadav (1973) and Yadav et al. (1993) for A. moestus (Fabricius). The occurrence of A. fimetarius in North America is confirmed.