XYLOTRUPINA Hope, 1845

Rowland, J. Mark & Miller, Kelly B., 2012, Phylogeny and systematics of the giant rhinoceros beetles (Scarabaeidae: Dynastini), Insecta Mundi 2012 (263), pp. 1-15 : 10

Subtribe XYLOTRUPINA Hope

Included genera. Allomyrina Arrow , Xylotrupes Hope , Trypoxylus Minck , Xyloscaptes Prell.

Description. Clypeus mesal margin: Slightly emarginate in Allomyrina , deeply emarginate in Xylotrupes , widely emarginate in Trypoxylus , entire in Xyloscaptes . Male cephalic horn apex: Bifurcate in all genera. Male cephalic horn armature: Adenticulate in Allomyrina and some Xylotrupes , denticulate in Trypoxylus , Xyloscaptes and other Xylotrupes ; denticles dorsal in some Xylotrupes , lateral in Trypoxylus and Xyloscaptes . Male cephalic horn length of longest-horned species: Medium in Allomyrina and Xyloscaptes , long in Xylotrupes and Trypoxylus . Male cephalic horn length of shortest-horned species: Medium in Allomyrina , Trypoxylus and Xyloscaptes , short in Xylotrupes . Female frons: Tuberculate with small tubercles in all genera; position mesal in Allomyrina , lateral in Xylotrupes , with both mesal and lateral tubercles in Trypoxylus and Xyloscaptes . Mandible incisor: Adenticulate in Allomyrina , Trypoxylus , Xyloscaptes and Xylotrupes florensis , denticulate in other Xylotrupes ; mostly asymmetrical and laterally dominant. Maxilla lacinia: Denticulate in all genera; denticles directed mesally, numbering four or more in Allomyrina and Xylotrupes , and three or less in Trypoxylus and Xyloscaptes . Dorsal pronotum of major males: With single mesal horn in all genera except Xylotrupes inarmatus . Mesal pronotal horns apex: Apically bifurcate in all genera except Xylotrupes inarmatus . Mesal pronotum dense pilosity: Present only in Allomyrina . Mesal pronotal accessory horns: Present only in Xylotrupes florensis . Male anterior ventrolateral pronotal apices: Developed as horns only in Allomyrina . Male pronotal horn length of longest-horned species: Short in Allomyrina and Trypoxylus , medium in Xyloscaptes , long in Xylotrupes . Male pronotal horn length of shortesthorned species: Short in Allomyrina and Trypoxylus , medium in Xyloscaptes , absent in Xylotrupes inarmatus . Pronotal architecture of female: Complex in Allomyrina , Trypoxylus and Xyloscaptes , simply convex in Xylotrupes ; architecture vague in Allomyrina , pronounced in Trypoxylus and Xyloscaptes . Pronotal integument of male: No anastomosing sculpture in any genus. Pronotal integument of female: Considerable anastomosing sculpture in Allomyrina , little anastomosing sculpture in Xylotrupes , Trypoxylus and Xyloscaptes . Prolegs: Sexually dimorphic in all genera. Elytra of female: Dorsal integument significantly different from male in Trypoxylus , essentially the same as in male in Allomyrina , Xylotrupes and Xyloscaptes . Dorsal integument color: Uniformly dark red/brown/black in all genera. Dorsal pilosity: Not conspicuous in Trypoxylus and Xyloscaptes , conspicuous in Allomyrina and Xylotrupes pubescens . Paramere dorsal conjunction: With interdigitating teeth in all genera; teeth strong, dominant tooth evaginates from left side into right side in Allomyrina , Xylotrupes and Trypoxylus ; teeth weak, dominant tooth evaginates from right side into left side in Xyloscaptes . Paramere apex: Lateral contours parallel or diverging outward. Paramere apex setation: Long and conspicuous. Raspulae: With enlarged, sclerotized spines in all genera.