When looking into beetles and discussions about beetles. You may have noticed the words “Major” and “Minor” being used to describe beetles. In Taiwan where beetles are very popular, they call it “長牙” and “短牙” which translates to “Long teeth” and “Short Teeth”. It's used to describe the different appearance males of the same species may take. It can be subject to a certain amount of subjectivity.
Major
“Major” beetles are typically larger in size, and can feature larger and longer mandibles or horns. Some beetles have very distinct differences between their major and minor counterparts.
For the beetles that do not have very distinctly different mandibles. We look at the mandible to body size ratio to determine if it is considered a Major or not.
Minor
Minor beetles are generally smaller in size than their major counterparts. Smaller mandibles/horns, and may even have completely different looking mandibles.
Here are some examples
Giraffa stag Major vs Giraffa stag Minor -
Rainbow stag Minor Rainbow stag Major
Major Xylotrupes philippinensis peregrinus Minor Xylotrupes philippinensis peregrinus
Minor Prosopocoilus hasterti moinieri Major Prosopocoilus hasterti moinieri
The case with these PHM are a little more uncommon. The minor PHM on the left is actually larger than the PHM on the right. However it does not have the shape of a Major.
here is also a “中牙” or “Middle Teeth” variant. But this is not yet currently recognized as much outside of Japan and Taiwan
All three of these beetles are of the same species. Prosopocoilus laterlis lorquini.
Beetle #1 is a Minor, he has short mandibles with little teeth like a saw, and has a slight windy curve to it.
Beetle #2 is a Middle Teeth, even though it has the long curved mandibles of a Major, it still has two teeth in the middle like that of a minor beetle.
Beetle #3 is a Major, as you can see his mandibles are very different compared to the minor beetle. It has a long smooth mandible with two teeth near the tip.
I hope these examples help give you a better idea about the differences between Major and Minor beetles, and helps you identify their differences yourself.
James