[Taxacom] type material and manuscript name

[Fabio Crocetta]

Dear all,
a question: if I have the author AA that described a species based on a manuscript by BB (in a few words the author AA described the species XY giving the authority as BB ms.). Now, the species has to be assigned to the author AA, right? And also the type material should be searched in the collection of the author AA, right? 

I'm asking that because the author BB in his collection under this name has a species, whilst the author AA in his collection under this name has a different species...

Thanks in advance
F.