Fig. 1

Summary of leading hypotheses of molluscan phylogeny. a Adenopoda hypothesis placing the aplacophoran clade Chaetodermomorpha as first offshoot and sister group to the remaining molluscan taxa (Neomeniomorpha + Testaria = Adenopoda) (after [39]). b Hepagastralia hypothesis placing the aplacophoran clade Neomeniomorpha as first offshoot and sister group to the remaining molluscan taxa (Chaetodermomorpha + Testaria = Hepagastralia) (after [36]). c Testaria hypothesis placing the shell-less Aplacophora (= Neomeniomorpha + Chaetodermomorpha) as sister group to all primarily shell-bearing molluscan taxa (Testaria) (after [47]). d Recently supported Aculifera hypothesis showing basal bifurcation by placing Aculifera (= Aplacophora + Polyplacophora) as sister group to all primarily single-shelled mollusks (Conchifera) (after [5])