The Japanese rhinoceros beetle is a big East Asian beetle whose males carry a long, forked head horn that they use like a lever to flip rivals off tree trunks. It's native to Japan, Korea, China, Taiwan, and Southeast Asia and doesn't live in the wild in the US. In Japan it's called kabutomushi and is one of the most popular pet insects.
Appearance
- Appearance
- Glossy reddish brown to dark brown. Males are about 1.2–2.2 in (30–55 mm) long without the horn and up to about 3.5 in (90 mm) with it, and have a second short horn on the thorax. Females are about 1.3–2.1 in (33–53 mm), have no long horn, and are duller.
Where it lives
- Typical habitats
- broadleaf forests
- oak woodlands
- Range
- East Asia: Japan, Korea, China, Taiwan, India, and mainland Southeast Asia south to Thailand, Laos, Vietnam, and Myanmar. Not found in the wild in the US.
- Preferred conditions
- Adults gather on oaks and other broadleaf trees that ooze sap. Larvae grow in soil rich in rotting leaves and wood.
Behavior
- Diet
- Adults drink sap from wounded trees, especially oaks. Larvae eat decaying wood and leaf mold.
- Activity
- Mostly active at night. By day adults hide in leaf litter or soil.
- Social life
- Big-horned males fight over sap sites and try to pry rivals off the tree. Smaller males often sneak in to mate instead of fighting.
Life cycle
- Breeding season
- Adults appear June–August in East Asia.
- Larva
- Females lay eggs in humus-rich soil from July to September. The C-shaped grubs feed underground, spend the winter there, and pupate the next June or July. One generation per year.
- Lifespan
- Adults usually live one to three months.
Name and classification
- About the name
- Long known as Allomyrina dichotoma. Several subspecies are recognized across its range, such as the Taiwan form (T. d. tsunobosonis) with a slimmer horn.
Conservation
- IUCN Red List
- NENot EvaluatedNot yet assessed
Culture and stories
- Culture and stories
- Scientists study it to learn how beetles grow such oversized horns.
- Its larvae are eaten in parts of East Asia, and it's used in traditional Chinese medicine.
More species to explore
Record what you meet and build your own collection
Your photos are kept with their date and place, and you can fill regional albums one species at a time.