#2
As far as I can tell:
The Dutch list once had
Erax punctatus. Later reserach showed that the correct name should have been
Erax punctipennis. Other research showed that
Erax punctatus was a junior synonym of
Erax barbatus. So I think the correct name for the Dutch species is
E. punctipennis and that records for the Netherlands of
E. barbatus are based on the (incorrect) older records of
E. punctatus. I do not know about other countries but I assume that some countries will have both species,
barbatus and
punctipennis.
#4
Sorry, very late answer:
There is - so far as we know - only one Erax species in Germany. (compare: http://www.asilidae.de/modules/general_comments/speckonz.htm). It should be the same as the dutch species. Using Weinberg & Bächli (1995) German specimens run to
Erax punctipennis, according to the genitalia, but we are so far not convinced that the characters used in this key are defined well enough.
The drawings of the male genitalia in lateral view are of bad quality and in the case of "barbatus" it does not fit very well with the corresponding drawing in dorsal view.
The length of the ovipositor in relation to the three last segments is no good character, too, because the length of these segments depends on various factors, both in living and in collection specimens.
Further investigations are necessary. We use the name "barbatus" just because of traditional reasons as long as the problem is not solved in a satisfying way.
Greetings, Danny