[Syrphidae] some help about Parhelophilus

[Pierre-Nicolas LIBERT]

Hi everybody,
In the last published keys of the genus Parhelophilus (Reemer, 2000), the 
first couplet of the key separes the species "consimilis" on the colour of 
the fore leg tibia: black on apical third (at least anteriorly) for 
"consimilis", entierely yellow for all other species.
The question is: in Verlinden's keys, he mentions the same couplet but say 
that a small black mark can appear for the other species than 
"consimilis"... so entierely yellow of with a small black mark????
Thanks for your help....
Pierre-Nicolas LIBERT
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