Onthophagus Latreille, 1802

Cheung, Kahong, Bai, Ming, Leung, Manhin, Lee, Yingming, Chan, Kinfung & Yang, Xingke, 2018, Scarabaeinae (Coleoptera: Scarabaeidae) from Hong Kong, Zoological Systematics 43 (3), pp. 233-267 : 247-248

Genus Onthophagus Latreille, 1802

Onthophagus Latreille, 1802 , Hist. Nat. Crust. Ins., 3: 141 (Type species: Scarabaeus taurus Schreber, 1759 ).

Monapus Erichson, 1847 , Naturg. Ins. Deutschl. Col., 3: 763 nota (Type species: Onthophagus mniszechi Harold, 1869 ).

Psilax Erichson, 1847 , Naturg. Ins. Deutschl. Col., 3: 763 nota (Type species: Onthophagus pronus Erichson, 1842 ).

Chalcoderus Erichson, 1847 , Naturg. Ins. Deutschl., 3: 763 nota.

Gonocyphus Lansberge, 1885 , Ann. Mus. Civ. Genova, 22: 382.

Tauronthophagus Shipp, 1895 , Entom., 28: 179.

Onthoellus Balthasar, 1959 , Sbornik Ent. Odd. Nár. Mus. Praze, 33: 466.

Key to subgenera of Onthophagus from Hong Kong.

1 Antennal scape markedly serrated on the outer margin; protibia not stongly extended and curved in male .......................................... ..................................................................................................................................... Onthophagus (Serrophorus) Balthasar, 1963 Antennal scape smooth or weakly serrated on the outer margin; if serrated, protibia strongly extended and curved in male..............2

2 The base of male pronotum with lobe-like backward projection and convex, the convex with parallel lateral ridges, or with horns at the front, or with triangular or polygonal disc............................................... Onthophagus (Paraphanaeomorphus) Balthasar, 1959 The base of male pronotum without lobe-like backward projection and not convex, without ridge, without horn at the front, without triangular or polygonal disc ................................................................................................................................................................. 3

3 Black or dark brown, sometimes metallic; elytra with knobs at the base; pygidium marginated at the base; male pronotum complex with base marginated, front margin of protibia straight, spurs of protibia strongly broaden and oblique; female head with two ridges, front ridge fine and long; body length of 7–14 mm ............................................ Onthophagus (Colobonthophagus) Balthasar, 1963 The above characteristics not present or not present at the same time ................................................................................................. 4

4 Male pronotum with two or more knobs in the central disc, with one longitudinal groove between the knobs; female pronotum simple; dark brown from dorsal view, or elytra in yellow sometimes with black spots; body length of 5–10 mm ............................................. ............................................................................................................................ Onthophagus (Gibbonthophagus) Balthasar, 1963 Male pronotum without two or more knobs in the central disc; female pronotum not simple, usually with horn(s) near the front ..... 5

5 The first segment of antennal club greatly developed and cup-like; male clypeus with tooth or T-shape projection on the front margin; head without horn; pygidial base marginated; black from dorsal view, or just head and pronotum with metallic sheen ....................... ................................................................................................................................. Onthophagus (Parascatonomus) Paulian, 1932 The first segment of antennal club not greatly developed and not cup-like; the rest of the above characteristics not present or not present at the same time .......................................................................................................................................................................6

6 Pronotum with projection near the front disc ........................................................... Onthophagus (Furconthophagus) Zunino, 1979 Pronotum without projection or with more than one projection near the front disc .............................................................................7

7 Prontum with one concave near front disc ................................................................................. Onthophagus (s. str.) Latreille, 1802 Prontum without concave near front disc....................................................................... Onthophagus (Matashia) Matsumura, 1938