auct.

[Craeymeersch, Johan]

In Hoisaeter (1986) (Sarsia, vol. 71) I find following synonyms:

Jujubinus Monterosato, 1884
   = Cantharidus auct., not Montfort, 1810

I thought this ment that one Cantharidus Monterosato, 1884 is synonymous
with Jujubinus Monterosato, 1884 but not with Cantharidus Montfort, 1810.
But, I also find:

Littorina arcana Hanaford Ellis, 1978
   = Littorina saxatilis auct., not (Olivi) in part
Littorina neglecta Bean, 1844
   = Littorina saxatilis auct., not (Olivi) in part

Does this mean that the name Littorina saxatilis has been used by three
autors: Ellis, Bean and Olivi? Or, has the name be used by two autors (Olivi
and ?) and has L. saxatilis not Olivi been split up in two species: L.
arcana and L. neglecta.

I hope one can help me.