A morphological comparison of Boucotinskia Brunton & Cocks, 1967 and Kozlowskiellina Boucot, 1957 makes a phylogenctic relationship between the two genera obvious. Boucotinskia is placed in the subfamily Cyrtinopsidinae. The subfamily Cyrtinopsidinae is probably very closely related to the Eospiriferinae and the Cyrtiinae.