[Taxacom] Correct spelling of a family name (again...) plus associated higher taxa

[Tony Rees]

Hi all, I am going through various higher taxon names of protists etc. in
my database and have come to the entries I have currently as
class Placididea, order Placidida, family Placididae (ICZN treatments) for
the new genus Placidia, as given in the original descriptions in:

Mayumi Moriya; Takeshi Nakayama; Isao Inouye (2002). A New Class of the
Stramenopiles, Placididea Classis nova: Description of Placidia
cafeteriopsis gen. et sp. nov. Protist 153(2), 143-156.
doi:10.1078/1434-4610-00093

My question is, whether these higher taxon names should correctly be
spelled with -ii- rahter than -i- , i.e.  class Placidiidea, order
Placidiida, family Placidiidae, as per the type genus which ends in -ia, or
whether something else is at play that renders the originally published
spellings correct.

Expert input would be appreciated,

Regards to all - Tony

Tony Rees, New South Wales, Australia
https://about.me/TonyRees
www.irmng.org