說明/ 雄蟲不含犄角體長約 4–6 公分，雌蟲無角，體長約 3–5 公分。外觀黑褐色有光澤，雄性成蟲的頭部長有一支兩邊對稱、雙分叉的巨型犄角。成蟲體型因幼蟲時期攝取食物的質與量不同而有差異，成蟲一般出現於 5 到 8 月。幼蟲稱為蠐螬或雞母蟲，生活於有機質含量高的土壤、朽木或腐植土中，吃腐質土維生，並於土中化蛹。分布於熱帶及亞熱帶中、低海拔山區， 在臺灣平地或山區皆可發現，活動於闊葉樹樹汁流出處附近。成蟲有趨光性，喜愛吸食樹液，尤其是光蠟樹（又稱白雞油）的樹液。（陸維元攝）

The male is about 4-6 cm in length, not including the horn, while the female is hornless, about 3-5 cm in length. It has a blackish-brown gloss. The adult male’s head is adorned with a giant horn that forks at the end. The adults’ sizes vary according to the quality and quantity of food they consume as larvae. Normally, adults appear between May and August. The larvae are called grubs, living in soils that are rich in organic matter or decaying wood and feeding on humus. The grubs then transform into pupas in the soil. It is distributed across low and medium altitude mountains in tropical and subtropical regions and can be found in the plains or mountains of Taiwan, living around broad-leaved trees that produce sap. The adults show phototaxis and like to feed on saps, in particular the sap of Formosan Ashes. (Photo courtesy of Lu)