Baltisphaeridium trifurcatum ssp. trifurcatum
Autonym.

Now Peteinosphaeridium trifurcatum ssp. trifurcatum (an acritarch subspecies). Originally Hystrichosphaeridium trifurcatum ssp. trifurcatum, subsequently Baltisphaeridium trifurcatum ssp. trifurcatum, thirdly (and now) Peteinosphaeridium trifurcatum ssp. trifurcatum (an acritarch subspecies).
Tax. sr. synonym of the acritarch subspecies Baltisphaeridium trifurcatum ssp. breuiradiatum (al. Peteinosphaeridium breviradiatum) Eisenack, 1959 ex Eisenack, 1965, according to Eisenack, 1969 and Turner, 1984, who believed Baltisphaeridium trifurcatum ssp. breviradiatum (al. Peteinosphaeridium breviradiatum) to be the sr. synonym.