Pycanum, Amyot & Serville, 1843

Ghate, Hemant V., More, Sadashiv & Magnien, Philippe, 2020, Description of a new species of the genus Pycanum (Hemiptera: Heteroptera: Tessaratomidae: Tessaratomini) from India with comments and key to extant species of the genus, Zootaxa 4809 (1), pp. 132-140 : 138-139

Key to the species of Pycanum

The group of species consisting of Pycanum alternatum (Lepeletier & Serville, 1828) and Pycanum pretiosum Stål, 1854 shows an amazing variability in all the external characters, and is utterly in need of a thorough study.

1 A black-rimmed whitish spot at the postero-internal angle of corium.............. Pycanum oculatum Jensen-Haarup, 1931

- no such spot at the postero-internal angle of corium.......................................................... 2

2 Pronotum almost quadrangular, anterior margin strongly angular, produced forward................................. 3

- Anterior margin of pronotum regularly rounded or weakly angular, if strongly angular then ground colour of habitus not ochraceous.......................................................................................... ……..4

3 Lateral margin of pronotum black-rimmed, the width of the rim about the same as the eye width (Fig. 3), underside purplish blue with green iridescence...................................................... Pycanum occidentale sp. nov.

- Black rim of pronotum very thin (Fig. 4), less than a quarter of the eye width, underside ochraceous............................................................................................... Pycanum ponderosum Stål, 1854

4 Dorsal side ochraceous, ventral side metallic blue on the thorax, metallic greenish on the abdomen; in males, vesica of phallus almost straight............................................................ Pycanum ochraceum Distant, 1893

- Dorsal side of various colours, often with metallic tinge, not ochraceous, if ochraceous then ventral side also ochraceous; in males vesica bisinuate, S-shaped..........................................................................5

5 Anterior margin of pronotum regularly rounded, third and fourth antennomeres subequal in length.................................................................................. Pycanum alternatum (Lepeletier & Serville, 1828)

- Anterior margin of pronotum margin somewhat angular, fourth antennomere longer than the third by about one third............................................................................ Pycanum pretiosum Stål, 1854