Buying Guide for Stag Beetles and Rhinoceros Beetles | How to Identify Healthy Individuals

The first step in starting to keep rhinoceros beetles and stag beetles is "purchasing individuals." However, it's often difficult to judge health condition based on appearance alone, and cases of specimens dying shortly after purchase are not uncommon. In this article, we will carefully explain the key points to keep in mind when purchasing, from how to identify healthy individuals to how to choose a trustworthy breeder.

Health Check Points

Key points that should always be checked before purchase are as follows.

Appearance Check

• Tarsi defects: Check that the claws on the legs are not chipped. Tarsi loss is a sign of aging or stress
• Body surface injuries or dents: Check that there are no dents or cracks in the elytra (wing covers). There may be incomplete metamorphosis
• Mandible damage (stag beetles): Check that the tips are not broken. Fighting individuals require caution
• Bent horns (rhinoceros beetles): If the pupal chamber was small, horns can become bent
• Mite infestation: Check that there are no large amounts of small mites on the body surface

Behavior Check

• Does it move actively: Does it have the strength to firmly grasp with its legs when touched?
• Is it eating: It's reassuring to have an individual that has confirmed post-feeding (started eating jelly)
• Can it right itself if flipped over: Individuals that cannot right themselves may be weakened

Verifying Size and Age

• Emergence date: Confirm when it emerged. Ideally a young individual within 3 months of emergence
• Actual size measurements: Check actual measurements (calipers) in addition to listing photos
• Post-feeding status: Individuals that have not yet post-fed are immature and cannot breed immediately