........Megasoma Kirby, 1825
........syn. Megalosoma Burmeister, 1847
........syn. Megasominus Casey, 1915
........syn. Lycophontes Bruch, 1910

Photo by Matthew R. Moore

Distribution of Megasoma species.

Distribution: Nearctic and Neotropical realms. Nearctic species found in the southwestern United States. Neotropical species range from northern Mexico south to Argentina.

Diagnosis: Moderate to large size, broadly truncate to emarginate clypeal apex with acute or toothed anterior angles, mandibles with two or three acute teeth, short prosternal process, and tridentate anterior tibia. Males all have a variably developed, bifurcate head horn, and the pronotum is armed or not (Ratcliffe and Cave 2006).

Revision or Synopsis:
Endrödi, S. 1976. Monographie der Dynastinae (Coleoptera) 6. Tribus: Dynastini. Acta Zoologica Academiae Scientiarum Hungaricae 22: 217-269.

Endrödi, S. 1985. The Dynastinae of the World. Series Entomologica, Volume 28, W. Junk, Dordrecht. 800 pp., 46 plates.

Hardy, A.R. 1972. A brief revision of the North and Central American species of Megasoma (Coleoptera: Scarabaeidae). Canadian Entomologist 104: 765-777.

Lachaume, G. 1985. Dynastini 1: Dynastes - Megasoma - Golofa. Les Coleopteres du Monde 5. Sciences Nat, Venette, France. 85 pp, 29 plates.

Ratcliffe, B.C. 2003. The dynastine scarab beetles of Costa Rica and Panama (Coleoptera: Scarabaeidae: Dynastinae). Bulletin of the University of Nebraska State Museum 16: 1-506.

Ratcliffe, B.C. and R.D. Cave. 2006. The dynastine scarab beetles of Honduras, Nicaragua, and El Salvador. Bulletin of the University of Nebraska State Museum 21: 1-424.

Composition: The genus Megasoma contains 15 species:

M. actaeon (Linnaeus, 1758); M. anubis Chevrolat, 1836; M. cedrosa Hardy, 1972; M. elephas (Fabricius, 1775); M. gyas (Herbst, 1775); M. joergenseni Bruch, 1910; M. lecontei Hardy, 1972; M. mars (Reiche, 1852); M. nogueirai Morón, 2005; M. occidentalis Bolívar y Pieltain, Jiménez-Asúa, and Martínez, 1963; M. pachecoi Cartwright, 1963; M. punctulatum Cartwright, 1952; M. sleeperi Hardy, 1972; M. thersites LeConte, 1861; M. vogti Cartwright, 1963.

Larvae: The larvae of Megasoma anubis, M. gyas, M. joergenseni, M. lecontei, M. mars, M. nogueirai are not described. Descriptions of the other third instar larvae are given by:

Morón, M.A. 1977. Description of the third-stage larva of Megasoma elephas occidentalis Bolívar et al. (Coleoptera: Scarabaeidae). Coleopterists Bulletin 31: 339-345.

Ratcliffe, B.C. and M.A. Morón. 2005. Larval descriptions of eight species of Megasoma Kirby (Coleoptera: Scarabaeidae: Dynastinae) with a key for identification and notes on biology. Coleopterists Bulletin 59: 91-126.

Van Dam, M., A. Van Dam, and M.D. Wilcox. 2006. Description of the third-instar larva and adult male of Megasoma sleeperi Hardy (Scarabaeidae: Dynastinae). Coleopterists Bulletin 60: 59-67.

Key to species

Species profiles: (click on species names)

Megasoma actaeon (Linnaeus, 1758) Megasoma anubis Chevrolat, 1836 Megasoma cedros Hardy, 1972 Megasoma elephas (Fabricius, 1775) Megasoma gyas (Herbst, 1775) Megasoma joergenseni Bruch, 1910 Megasoma lecontei Hardy, 1972 Megasoma mars (Reiche, 1852) Megasoma nogueirai Morón, 2005 Megasoma occidentale Bolívar y Pieltain, Jiménez-Asúa, and Martínez, 1963 Megasoma pachecoi Cartwright, 1963 Megasoma punctulatum Cartwright, 1963 Megasoma sleeperi Hardy, 1972 Megasoma thersites LeConte, 1861 Megasoma vogti Cartwright, 1963