Orobanche elatior

Dear Holger,

could you please explain in more details, why do you think that this plant belongs to O. kochii?
I've checked the paper of Jiri Zazvorka on both species, and in my opinion, the plant has all the distinguishing features of O. elatior, i.e. the size (appr. 50 cm), the dense, narrow inflorescence, brownish colour without a tinge of red, regularly curved corolla and narrow long leaves. Concerning the flower time, this specimen was one of the last remaining flowering plants in this population (as it grew in half-shade), while the vast majority of them were becoming withered by the time of my visit.
The population with several dozens of plants was found in the nature reserve Froschberg by Blankenheim in Nordrhein-Westfalen, it is well known to local botanists and some additional information can be even found on internet.

Dear Holger,

do you mean the paper of Dr. Jiri Zazvorka 'Orobanche kochii and O. elatior (Orobanchaceae) in central Europe' published n Acta Musei Moraviae, Scientiae biologicae (Brno) 95(2): 77–119, 2010? I've checked the paper already, and in my previous post I've listed the features, which in my opinion, allows to determine this plant as O. elatior and distinguish it from O. kochii. I'd greatly appreciate to hear your opinion on them.
By the way, in his paper Dr. J. Zazvorka cites several pictures illustrating O. elatior s. str., and among them the photographs published by Carel Kreutz in his book 'Orobanche: The European Broomrape species. Central and Nothern Europe'. Notably, two of the pictures were made in Nonnenbach, Eifel on 8-7-1988. To me, there is no significant differences between the discussed plant and those shown in the book. Moreover, they likely belong to the same population, as the nature reserve Froschberg is situated between Blankenheim and Nonnenbach.