Eupatorus siamensis (Laporte de Castelnau, 1867)

Prandi, Massimo & Grossi, Paschoal C., 2021, A new species of Eupatorus Burmeister, 1847 related to Eupatorus birmanicus Arrow, 1908 from southwestern China (Coleoptera: Scarabaeidae: Dynastinae), Zootaxa 4966 (1), pp. 29-40 : 39

Identification key for major males of the Eupatorus siamensis species group

Identification of minor males requires the examination of the aedeagus and collection localities

1 Dorsum glabrous, pronotal disc bearing two (thoracic) horns.............................. 2 ( siamensis species group)

- Different combination of characters....................................................other Eupatorus species

2 Thoracic horns divergent and not spatulate................................................................. 3

- Thoracic horns parallel and spatulate...................................................................... 4

3 Habitus dark-chestnut ( Fig. 4A–C )......................................... Eupatorus siamensis ( Laporte, 1867)

- Habitus glossy black ( Fig. 4B–D )................................................. Eupatorus endoi Nagai, 1999

4 Cephalic horn C-shaped ( Fig. 1B–D )......................................... Eupatorus birmanicus Arrow, 1908

- Cephalic horn “sinusoidal”, S-shaped ( Fig. 1A–C )..................... Eupatorus pyros Prandi & Grossi , new species

Figures

FIGURES 1A–D. Habitus of males in dorsal view and detail of thorax in lateral view. A, C, holotype of Eupatorus pyros Prandi & Grossi, new species; B, D, Eupatorus birmanicus Arrow, 1908.

FIGURES 4A–D. Habitus of males in dorsal view and detail of thorax in lateral view.A, C, Eupatorus siamensis Laporte, 1867; B, D, Eupatorus endoi Nagai, 1999.