どちらもP.primigeniusに非常によく似ていて、
主に交尾器で分けられたようです。
記載文はロシア語で書かれていて　まったくわかりません(笑)
タイプ標本はモスクワの博物館にすべて納められているそうです。

Platycerus perplexus Gusakov,2004:26-27,fig.1
[Type Locality] ロシア語でどこかわかりません！

Platycerus vicinus Gusakov,2004:26-28,fig.3
[Type Locality]

記載文の絵　Gusakov,2004より


Four new species of the palaearctic lamellicorn beetles (Coleoptera: Scarabaeoidea) are described. Platycerus perplexus Gusakov, sp. nov. (Lucanidac), which are described from Azerbaijan (Talysh), north-eastern Georgia (Lagodekhi) and Russia (north-western Daghestan), is very similar to P. primigenius E. Weise, but differs by penis structure. Platycerus vicinus Gusakov, sp. nov. from Georgia and northern areas of Armenia is very similar to P. primigenius and P. perplexus, but differs from the latter by penis structure.
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