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Species Dynastes grantii - Grant's Hercules Beetle

AZ Dynastes granti - Dynastes grantii - male Western Hurcules Beetle - Dynastes grantii - male Malformed Dynastes - Dynastes grantii - male Hercules Beetle - Dynastes grantii - male Grant's Hercules Beetle - Dynastes grantii - male - - Dynastes grantii - female Western Hercules Beetle (?) - Dynastes grantii Scarabid - Dynastes grantii
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Polyphaga (Water, Rove, Scarab, Long-horned, Leaf and Snout Beetles)
Superfamily Scarabaeoidea (Scarab, Stag and Bess Beetles)
Family Scarabaeidae (Scarab Beetles)
Subfamily Dynastinae (Rhinoceros Beetles)
Tribe Dynastini
Genus Dynastes (Hercules Beetles)
Species grantii (Grant's Hercules Beetle)
Other Common Names
Grant's Rhinoceros Beetle, Western Hercules Beetle
Explanation of Names
Dynastes grantii Horn 1870
Type Locality: Fort Grant, Arizona
males, including horn, 50-85 mm length
Distinctive in its Southwestern range.
AZ-NM-UT / n. Mexico (Chihuahua).
Aug-Nov (BG data)
Larvae are found in rotten wood. (1)
Adults usually found in association with Arizona Ash (Fraxinus velutina, Oleaceae)
Life Cycle
Adults are most often collected at lights (Menke and Parker 1988)
Dynastes grantii is the largest scarab in the w. US, and is relatively common in Arizona.
but is considered by New Mexico to be a "Species of Greatest Conservation Need" (SGCN) (2)
at high risk of endangerment due to the EAB (3)
See Also
Dynastes tityus - Eastern Hercules Beetle
Print References
Horn, G.H. 1870. Contributions to the coleopterology of the United States. Transactions of the American Entomological Society, 3: 69-97. (Full PDF)
Menke, A.S. & F.D. Parker. 1988. Adult feeding and distribution of Dynastes granti Horn (Coleoptera: Scarabaeidae). Coleopterists Bulletin, 42(2): 161-164.
Internet References
Texas Entomology - Mike Quinn, 2007
University of Nebraska State Museum - Matthew R. Moore, 2006
Works Cited
1.White Grubs and Their Allies, a Study of North American Scarabaeoid Larvae
Paul O. Ritcher. 1966. Oregon State University Press, Corvallis. 219 pp.
2.New Mexico "Species of Greatest Conservation Need" (SGCN)
3.Ecological impacts of the emerald ash borer. Pp. 15-62. In: R.G. Van Driesche (ed.), Biology and Control of Emerald Ash Borer.
Wagner, D.L. and K. Todd. 2015. USDA Technical Bulletin FHTET-2014-09. Morgantown, WV.