Key to Japanese species of the genus Cryptus (Female only)

(Female of Cr. lugubris atrifemur is unknown)

1. Metasomal tergites largely red or orange (Figs 6D, E)....................................................................................2

-. Metasomal tergites without large red or orange area.................................................................................3

2. Metasomal tergites red except for base of T I and T IV (excluding base) to apex of metasoma. Flagellum with a white band. Body usually longer than 10 mm. .............................. Cr. dianae (Gravenhorst, 1829)

-. Metasomal tergites entirely orange except for base of T I (Figs 6D, E). Flagellum without a white band (Fig. 6D). Body shorter than 8.5 mm. ....................................... Cr. daidaigaster sp. nov.

3. Legs nearly entirely black. Antenna without a white band. Apex of metasomal tergite without a white spot. ....................................... Cr. konoi Uchida, 1936

-. Femora reddish brown to red. Antenna with a white band. Apex of metasomal tergite with or without a white spot.............................................................................4

4. Apex of T VII without a white spot. Fore and mid coxae each entirely black. ...................................... Cr. spiralis (Fourcroy, 1785)

-. Apex of T VII with an oval white spot. Fore and mid coxae each black with yellow area. ...................................... Cr. nipponensis Uchida, 1930 (not seen by the author)