S. Mahunka szerk.: Folia Entomologica Hungarica 54. (Budapest, 1993)

Comparative studies My present studies are based on the females of the above species and the males which are well identifiable. These males are: P. kirbyi Dahlb., P. clitellatus Lep., P. xanthocarpus Htg. I clustered these species into two subgroups. One comprising clitellatus, kirbyi and trisignatus, while the other truncatus and xanthocarpus. The members of these two subgroups are in close relation with one another. The characteristic features of the species concerned may be found in the identification key below. My comparative studies elucidated the real male of P. truncatus Benson and that of P. trisignatus Förster. Identification key of the P. clitellatus species-group Females 1(6) Basic colour yellow with black spots. Black is the mesosternum, the upper and lower margin of the mesopleuron, the epimeron. Mesonotum with black stripes, metanotum black. Scutellum with black spot or entirely black. Sometimes meso- and metanotum entirely suffused, but pale basic colour still seen. Mesopleuron yellow, never black with a small yellow spot. 2(5) Smaller, 5-7 mm long species. Abdomen entirely yellow or with separated black stripes on tergites. 3(4) Yellow, except for a small spot on the head above, the entire mesosternum, the three stripes on the mesonotum black. Tergites rarely with brown bands kirbyi (Dahlbom, 1835) 4(3) The black spot on head larger, black stripes on mesonotum also wider. Tergites with black bands clitellatus (Lepeletier, 1823) 5(2) Larger, 8-9 mm, long species. Abdomen all black in dorsal view except for the two apical tergites trisignatus (Förster, 1854) sp. rev. 6(1) Basic colour black with some yellow spots. Meso- and metanotum all black whitout yellow colour. 7(8) Mostly black, though pronotum, a small spot on the middle-hind part of the mesopleuron, head around the eyes and postocellar area partly, abdomen beneath and the last two apical tergites yellow truncatus Benson, 1948 8(7) All body black, only the apical sternite of the abdomen and the base of the sawsheath and more or less the tegula yellowish white xanthocarpus (Hartig, 1840) Males 1 (6) Projection from eighth tergite subtruncate at apex, without a medial carina or sulcus (Figs 1, 3, 4). Spur of penis valve alongside dorsal flap. 2(5) Smaller, 5-7 mm long species. Mesopleuron smooth. 3(4) Projection from eighth tergite and penis valve as in Fig. 1 clitellatus (Lepelletier, 1823) 4(3) Projection from eighth tergite and penis valve as in Fig. 4 kirbyi (Dahlbom, 1835)