© Bugman95 / Public domainTsushima Flat Stag Beetle
The Tsushima Flat Stag Beetle is a subspecies of flat stag beetle native to Tsushima Island in Nagasaki Prefecture, as well as the Korean Peninsula and northern China. Its defining feature is a long, straight pair of mandibles — wild-caught individuals can exceed 80mm, making it one of the longest stag beetles found in Japan. Males typically grow to 50–87.4mm and females to 25–40mm, giving the species an impressively bold presence that draws keepers in. Many individuals have a relatively calm temperament, though larger specimens are strong and should be handled carefully. Adults live around two to three years, longer than many other stag beetles, making this a species you can enjoy keeping over time. Basic care follows standard flat stag beetle husbandry, but raising an individual with well-developed mandibles takes some skill with temperature management, making it best suited to keepers with some prior experience.
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About Tsushima Flat Stag Beetle
A flat stag beetle subspecies from Tsushima Island with long, straight mandibles reaching over 80mm in the wild — among Japan's longest. Males 50–87.4mm, females 25–40mm; adults live 2–3 years. Best suited to keepers with some experience.
7 things to know before welcoming a Tsushima Flat Stag Beetle
1Exceptionally Long Mandibles
The Tsushima Flat Stag Beetle's defining trait is its long, straight mandibles — wild individuals can exceed 80mm, making it one of the longest stag beetles found in Japan. In captivity, you can fully appreciate this impressively bold jaw structure.
2Watch the Temperature
Like other flat stag beetles, this species is sensitive to heat, so avoid direct sunlight and poorly ventilated rooms where temperatures can spike in summer. Keep the enclosure somewhere well-ventilated with stable temperatures.
3A Powerful Bite Grip
Males with well-developed mandibles have a surprisingly strong grip and can cause injury if handled carelessly. When handling, avoid the base of the mandibles and move calmly and steadily.
4Adults Live 2–3 Years
Adult Tsushima Flat Stag Beetles typically live for two to three years, making them relatively long-lived among stag beetles. Keeping them at moderate temperatures and avoiding excess dryness helps them thrive over the long term.
5House Them Individually
Two males — or even a male and female outside of pairing — can injure each other if kept in the same enclosure. Keep each beetle in its own container except during intentional pairing.
6Provide Substrate and Footing
Line the enclosure with insect substrate designed for stag beetles and add climbing wood so the beetle has secure footing. Mist the substrate periodically to keep it from drying out.
7Prepare Supplies in Advance
Have an enclosure with substrate, insect jelly, and climbing wood ready before your beetle arrives so you can start care right away. As a species suited to keepers with some experience, it helps to know the basics of stag beetle care beforehand.
Frequently asked questions about Tsushima Flat Stag Beetle
- Q.How large does the Tsushima Flat Stag Beetle grow?
- A.Males grow to about 50–87.4mm and females to 25–40mm. Wild-caught individuals have been found exceeding 80mm, making this one of the longest stag beetles in Japan.
- Q.How difficult is this species to keep?
- A.It's considered a mid-level species, suited to keepers with some prior experience. Basic care follows standard flat stag beetle husbandry, but raising larger individuals calls for more attention to temperature and enclosure conditions.
- Q.How long do adults live?
- A.Adults typically live around two to three years. That's relatively long for a stag beetle, so you can enjoy keeping one over an extended period.
- Q.Can males and females be kept together?
- A.Outside of intentional pairing, it's safer to avoid housing them in the same enclosure. They can injure each other with their mandibles, so individuals are generally kept separately.
- Q.Where is this species found besides Tsushima?
- A.Beyond Tsushima Island, it's also found on the Korean Peninsula and in northern China. Individuals from different regions can show slight variation in characteristics.
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