by Euchroeus » 06 Jun 2021 16:37
Hi Jochem,
thanks for your pictures.
The distinction between Ps. auratus and Ps. triangulifer is not always easy and immediate, and needs experience.
The easiest way to separate the two species is looking at the lenght of the antennal segments.
If the median flagellomeres are longer than broad, then it is Ps. triangulifer.
However, this character is less evident in males.
Moreover, the shape of the median notch on the last visible tergum is more variable in specimens of Central and Southern Europe and the median notch may be deeper than broad, as in your specimen.
Taking in consideration this two morphological observations, and based on your images, I would ID your female as Ps. triangulifer, however I can be wrong without direct examination.
I hope this may help.
Cheers
Paolo