KEY TO THE ALPINE SPECIES OF PHILOCTETES
1- Body entirely blue, green to dark green in both sexes (Figs. 1-6) .................................................................. 2
- Body distinctly bicoloured: head and mesosoma green, green-blue or blue contrasting with red or golden-red T1, T2, and often T3 as well. Male sometimes dorsally darkened, but bicoloured in lateral view ........ 4
2- Metascutellum with large, elongated parallel sided projection (Figs. 4B, 5B, 6B, 7B,D,F) ...................... .......................….… Ph. putoni (du Buysson, 1892)
- Metascutellum without projection, sharply angled or slightly protruding (Figs.1B, 2B, 7A,C, 7 E) ........…3
3- Body covered with short (up to 1.5 MOD)standing white setae. In lateral view, metascutellum sharply convex; apical median notch on T3 with thick border; posterolateral margins of T3 sinuous ….......................…… ………....………...... Ph. truncatus (Dahlbom, 1831)
- Body covered with long (up to 2 MOD) standing black setae (Figs. 1D, 2D); in lateral view metascutellum slightly protruding (Figs. 1B, 2B,C, 7C), and in dorsal view triangularly shaped (Fig. 7A); apical median notch on T3 with thin border, posterolateral margins of T3 uniformly arched (Figs. 1D, 2D) .............…..…. Ph. helveticus (Linsenmaier, 1959)
4- T1 and T2 red or golden red, distinctly contrasting with green or light blue T3. T3 margin with a shallow median notch, and uniformly arched laterally. T3 without transverse swelling or thickened rim ….............................. ...................... Ph. bogdanovii (Radoszkowski, 1877)
-T1,T2,andT3uniformlyredorgoldenred.T3marginwitha deepmediannotch,andsinuouslaterally,orapicalmargin of T3 with transverse swelling and shallow notch ..... 5
5- Margin of T3 with a shallow median notch, transverse swelling, and uniformly arched sides …......... .............................. Ph. punctulatus (Dahlbom, 1854)
- Margin of T3 with deep median notch, no transverse swelling, and sinuous sides (in male sometimes less evidently so) .......... Ph. bidentulus (Lepeletier, 1806)