Grant's Hercules Beetle
Dynastes grantii
This record describes Dynastes grantii (species). Recorded family: Scarabaeidae. Recorded order: Coleoptera.
Identification and Appearance
Distinctive in its Southwestern range. 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) ( 3 ) at high risk of endangerment due to the EAB ( 4 )
Identification notes
Distinctive in its Southwestern range.
Classification
- Kingdom
- Animalia
- Phylum
- Arthropoda
- Class
- Insecta
- Order
- Coleoptera (Beetles)
- Suborder
- Polyphaga
- Superfamily
- Scarabaeoidea
- Family
- Scarabaeidae (Scarab Beetles)
- Subfamily
- Dynastinae
- Tribe
- Dynastini
- Genus
- Dynastes (Hercules Beetles)
Imported taxonomy record. Source availability varies; see the source references and editorial policy below.
Habitat and Range
Geographic Range
sw.UT-AZ-s.NM / nw. Mex. - Map
Seasonal Activity
mostly Aug-Sept
Diet and Behavior
Diet: Larvae are found in rotten wood. Records have been made on sycamore Platanus occidentalis and Platanus racemosa . Adults usually found in association with Arizona Ash ( Fraxinus velutina , Oleaceae)
Life History
Adults are most often collected at lights (Menke and Parker 1988)
Additional species information
Species notes from the sources
Etymology: Dynastes grantii Horn 1870
About Primitive Winged Insects: the wider group
Order-level background for Coleoptera, the group containing Dynastes grantii. Species-specific details appear above.
Group overview
Coleoptera is the largest order of insects with over 400,000 described species, representing ~25% of all known animal species and ~40% of all insects. In the U.S. alone, nearly 30,000 beetle species have been identified.
Ecological role of the group
Beetles are prominent decomposers, especially in forests, breaking down dead wood and recycling nutrients. As predators, they reduce populations of pest insects. Many species are also important pollinators of flowering plants.
Economic and practical significance of the group
Beetles have major economic significance: leaf beetles (Chrysomelidae) and weevils (Curculionoidea) are among the most destructive agricultural pests globally, costing billions annually, while predatory species like ladybugs provide natural pest control.
Recorded sources for this group: Britannica, Smithsonian, NCSU Entomology. Imported estimates may describe particular regions or reporting periods.
Photos of Grant's Hercules Beetle (5)
Photo credits: Contributed by Cotinis; Additional contributions by Beatriz Moisset , Phillip Harpootlian , Bbarnd , Chuck Entz , Mike Quinn , David Ferguson , Arturo Santos
Frequently Asked Questions About Grant's Hercules Beetle
What is Grant's Hercules Beetle?
Grant's Hercules Beetle (Dynastes grantii) is a species in the family Scarabaeidae, within the order Coleoptera.
How big is Grant's Hercules Beetle?
males, including horn, 50-85 mm length
How do you identify Grant's Hercules Beetle?
Distinctive in its Southwestern range.
Where is Grant's Hercules Beetle found?
Range: sw.UT-AZ-s.NM / nw. Mex. - Map
What does Grant's Hercules Beetle eat?
The diet of the Grant's Hercules Beetle includes Larvae are found in rotten wood. Records have been made on sycamore Platanus occidentalis and Platanus racemosa . Adults usually found in association with Arizona Ash ( Fraxinus velutina , Oleaceae).
When is Grant's Hercules Beetle active?
Grant's Hercules Beetle: seasonal activity - mostly Aug-Sept.
What is the life cycle of a Grant's Hercules Beetle?
Adults are most often collected at lights (Menke and Parker 1988)