A molecular phylogeny and revision of the genus Pyropteron Newman, 1832 (Lepidoptera, Sesiidae) reveals unexpected diversity and frequent hostplant switch as a driver of speciation Author Bartsch, Daniel daniel.bartsch@smns-bw.de Author Pühringer, Franz f.puehringer@sesiidae.net Author Milla, Liz liz.milla@csiro.au Author Lingenhöle, Arthur arthur.lingenhöle@gmx.de Author Kallies, Axel 0000-0002-3778-2187 axel.kallies@unimelb.edu.au text Zootaxa 2021 2021-05-18 4972 1 1 75 journal article 6247 10.11646/zootaxa.4972.1.1 cdd9688e-9a3f-4602-992e-1f8693caab9b 1175-5326 4771798 E78473FE-5662-409A-90C2-7C4912DC57E8 Pyropteron chrysidiformis (Esper, 1782) This is a highly variable species, both in extent and intensity of the reddish coloration and in size and shape of the transparent areas. In particular the ETA can be present or absent; thus, the entire forewing can be covered by red or orange scales, apart from costal area, the proximal part of discal spot and the distal margin. However, in some specimens the reddish colour is restricted to the anal margin and an area distal of the discal spot. Some specimens are more or less completely black, especially in the south-western parts of the range. FIGURES 31–38. Pyropteron Biology. 31–34. Pyropteron erodiiphaga , (31) male, reared, (32) larva in root of Erodium arborescens , (33) habitat with host plant Erodium arborescens , Tunisia, Djerba (images Friedhelm Mai), (34) male, Morocco, Middle Alas, Col du Zad. 35. Pyropteron affinis , male, Austria, Tirol, Zirl (images FP). 36–38. Pyropteron meriaeformis , (36) habitat with host plant Rumex acetosella , France, Corsica, Ghisonaccia (image DB), (37) male, reared, Portugal, Guarda, Pinzio (image Zdeněk Laštůvka), (38) female, old specimen, France, Corsica, Ghisonaccia (image DB). FIGURES 39–46. Pyropteron Biology. 39. Armeria canescens , hostplant of Pyropteron hellenicum , Greece, Epirus, Timfi Mts, Gamila. 40–41. Pyropteron borreyi , (40) female, Morocco, High Atlas, Oukaimeden, (41) male, Morocco, Middle Alas, Col du Zad. 42–43. Pyropteron maroccana , males, Morocco, High Atlas, Oukaimeden (images FP). 44. Pyropteron hispanica , female, reared, Spain, Toledo, Buenasbodas. 45–46. Pyropteron koschwitzi , (45) male, reared, Spain, Aranjuez, (46) female, reared, Spain, Castile, Navacepedilla (images Zdeněk Laštůvka). DNA barcode analyses group P. chrysidiformis into two distinct clusters, which differ by an average of 6.8%, the chrysidiformis clade, with specimens from western Europe, including north-western Italy , Corsica and Sardinia , and the sicula clade with specimens from Sicily , Apulia , Adriatic Italy and Istria. These two clades are well supported and could be considered different species. However, although there are some external differences between specimens of the two clades, these were not consistent across the whole range and we did not find significant differences in the genitalia. We therefore follow the current practise ( Špatenka et al. 1999 , Pühringer & Kallies 2004 ) and consider these two clades subspecies. Note. Sesia lecerfi Oberthür, 1909 is not a synonym of P. chrysidiformis , with which it was compared in the original description and as proposed by subsequent authors ( Laštůvka 1990c , Špatenka et al. 1999 ). The holotype from the Eastern Pyrenees is an almost completely black male of a Bembecia species. Due to the shapes of the transparent areas of the forewing, the relatively large size with an alar expanse of 23 mm and the dark red colour of the forewing discal spot and anal margin (yellow or orange-red in most congeners), we consider it most likely to be conspecific with Bembecia ichneumoniformis ([Denis & Schiffermüller], 1775) and synonymize it with this species ( syn. nov. ). However, this issue needs to be re-addressed by examination of the genitalia or DNA-analysis of the holotype .