Information: Cheirotonus formosanus, is a rarer endemic species living in mountain forests in Taiwan. The species was described by Ohaus in 1913. C. formosanus has a distinctive attractive appearance and the males have extremely long front legs, for which it received the folk name: Long Armed Scarab.
The largest scarab beetle in Taiwan. Body length 50 - 65mm. Fore-legs length 90 - 100 mm in male, much longer than in female. Body color metallic dark-brown. Central of clypeus concave, outer edge slightly protruded with small processes on it. Pronotum with a wide central furrow and outer edge toothed. Elytra surface with scattered brown spots; Ventral of abdomen covered with short yellow hairs.
Body length: 50 - 65 mm
Peak activity: May - October
Remarks: The species is active on the light trap.
Distribution: Taiwan
Zoogeographic region: Palearctic
Taxonomic classification:
The Scarabaeidae of Taiwan | Ching-Jin Yu 2000
Material examined (& observation):
Taiwan 
Hsinchu Prov.
Neiwan env. 內灣
(GPS) 
Altitude 1600 m a.s.l. | 15.6.2013
Our observation period: May ~ June
Sampling Methods: Attracted to light trap 
Taiwan (Province of China)The Dynastidae of the World
Cheirotonus formosanus
Immature stages of Euchirinae Genera Cheirotonus and Propomacrus, Šípek et al 2011.pdf
