Baltisphaeridium hirsutum, (Ehrenberg, 1838), Downie and Sarjeant, 1965

Name not validly published since Ehrenberg, 1838 did not intend to introduce a new species.
Originally Xanthidium hirsutum (a desmid species, Appendix A; name not validly published), subsequently Ovum hispidum ssp. hirsutum (name not validly published), thirdly Hystrichosphaera hirsuta (name not validly published), fourthly Hystrichosphaeridium hirsutum (name not validly published), fifthly Baltisphaeridium hirsutum (name not validly published), sixthly Operculodinium hirsutum (naIne not validly published), seventhly Operculodinium? hirsutum (name not validly published). According to Fensome et al., 1990: "It is apparent from the discussion given by Sarjeant, 1984 that Ehrenberg, 1838 did not intend to introduce a new taxon but was comparing fossil specimens with Xanthidium (now Staurastrum) hirsutum Ehrenberg, 1838, a species of extend desmids. Thus the microfossil species name Xanthidium hirsutum and derivatives (Hystrichosphaeridium hirsutum, Hystrichosphaera hirsuta and Operculodinium hirsutum) are not validly published according to I.C.B.N. Article 34.1a. The specimen illustrated and provisionally identified as Xanthidium hirsutum by Ehrenberg, 1838 is a specimen of Coronifera striolata, ... according to Sarjeant, 1984. This name was not validly published in Klement, 1960 additionally since that author did not fully reference the basionym.

Holotype: Downie, 1958, pl.16, fig.1
Age: Cretaceous