M. constructus Young, 1954: (Type species) The holotype specimen, represented by a partial skeleton that was 13 m (43 ft) long, from the Hantong Formation M. hochuanensis Young & Zhao, 1972: Four partial skeletons.
M. constructus Young, 1954: (Typeart) holotype-eksemplareret, der er repræsenteret af et delvist skelet der var 13 m langt fra Hantongformationen M. hochuanensis Young & Zhao, 1972: Fire delvise skeletter.