Characteristics
Labrum hidden beneath clypeus. Clypeus with apex bidentate, rounded, acuminate, or truncate. Mandibles variable: Cyclocephalini and some Phileurini lack teeth on lateral edge of mandibles, other tribes and other Phileurini with teeth or lobes. Antennae 9-10 segmented, club usually small and with 3 segments. Scutellum normal, never enlarged. Procoxae transverse. Mesotibial apex with 2 spurs; spurs mesad, adjacent (not separated by basal metatarsal segment). Tarsal claws all subequal in size except for males of most Cyclocephalini and some Pentodontini where protarsal claws enlarged. Male genitalia diagnostic in nearly all species.

The sexes are usually dimorphic (except Phileurini and some Cyclocephalini and some Pentodontini) with males having either horns or enlarged tubercles or enlarged foretarsi.

Classification Status
The subfamily is divided into eight tribes, and six occur in the New World. Members of the Hexodontini are restricted to Madagascar and the Oryctoderini are found in the Oriental and Australian regions.

Distribution
In the New World there are approximately 87 genera (Ratcliffe 1981; Endrodi 1985). Keys to adults: Endrodi 1985. Keys to larvae: Ritcher 1966. World catalog: Endrodi 1985.

New World Tribes of Dynastinae
Cyclocephalini
Pentodontini
Oryctini
Phileurini
Agaocephalini
Dynastini

TRIBE CYCLOCEPHALINI
Characteristics. Head and pronotum lacking tubercles, horns, carinae, or foveae in both sexes. Club of antennae longer in some males of Cyclocephala. Mandibles without teeth or lobes on lateral edge. Legs with all tarsi cylindrical, never subtriangular. Anterior tarsi enlarged in males of most species. Prosternal process usually prominent. Onychium at apex with two setae.

This tribe of 13 genera is restricted to the New World except for one monobasic genus, Ruteloryctes, in Africa. Keys to species: Saylor 1945; Endrodi 1985; Ratcliffe 1991.

TRIBE PENTODONTINI
Characteristics. Head and pronotum with carina, tubercles, or fovea. Club of antenna usually small. Mandibles usually with 1-3 lateral lobes or teeth. Apex of posterior tibiae generally truncate or finely crenulate, not toothed. Prosternal process long, columnar. Onychium at apex usually with two setae.

The Pentodontini is the largest tribe of Dynastinae, and its species occur everywhere except for the polar regions. There are 25 genera in the New World. Keys to genera: Ratcliffe 1981; Endrodi 1985. Keys to species: Endrodi 1985. KEY to genera.

TRIBE ORYCTINI
Characteristics.Head and pronotum with tubercles or horns (especially males) and pronotum usually with fovea (especially females). Club of antenna small. Mandibles with lateral lobes or teeth. Apex of posterior tibia strongly crenulate or with teeth (including apical tooth). Prosternal process prominent, columnar. Onychium with 3 or more setae at apex.

The Oryctini is world wide in distribution. There are 13 genera in the New World. Key to genera and species: Endrodi 1985.

TRIBE PHILEURINI
Characteristics. Head with tubercles or short horns, pronotum with median sulcus and usually with apical tubercle. Club of antenna small. Mandibles exposed, narrowly subtriangular, with or without teeth. Mentum large, covering base of labial palps. Clypeus with apex acute, rounded, or with short horn. Apex of posterior tibia truncate or with teeth. Apex of basal tarsomere on posterior leg with long spine.

Phileurines are found in all regions of the world although most species are found in the tropics. There are 21 genera in the New World. Key to genera: Endrödi 1985.

TRIBE AGAOCEPHALINI
Characteristics. Head and pronotum with horns or tubercles. Club of antenna usually small. Mandibles broad, with or without teeth. Elytra irregularly punctate, not with distinct double rows of punctures. Propygidium without stridulatory area.

Members of the Agaocephalini are found only in the New World tropics where there are 11 genera with about 40 species (Endrödi 1985). Key to genera and species: Endrödi 1985.

TRIBE DYNASTINI
Characteristics. Head and pronotum usually with horn (males) or head with tubercle (females). Prosternal process flattened, subtriangular, generally adpressed to prosternum, usually short. Onychium at apex multi-setose.

The tribe Dynastini is comprised of three genera in the New World. Members of the Dynastini are among the largest insects on Earth, and the males of some species possess very large horns. Key to genera and species: Endrodi 1985. KEY to genera.

References Cited
ENDRODI, S. 1985. The Dynastinae of the World. Dr. W. Junk Publisher, Dordrecht. 800 pp., 46 plates.

RATCLIFFE, B. C. 1981. Barutus hartmanni, a new genus and species from Panama with a key to the genera of New World Pentodontini (Coleoptera: Scarabaeidae: Dynastinae). Coleopterists Bulletin 35: 463-472.

RITCHER, P. O. 1966. White Grubs and Their Allies: A Study of North American Scarabaeioid Larvae. Oregon State University Press, Corvallis. 219 pp.

SAYLOR, L. W. 1945. Synoptic revision of the United States scarab beetles of the subfamily Dynastinae, No. 1: tribe Cyclocephalini. Journal of the Washington Academy of Sciences 35: 378-386.