Hippuritoida

found: Treatise invert paleon.:p. N121 (Rudista proposed as 1 of 4 orders of class Acephalophora) p. N741 (Hippuritoida: rudists and pachydonts) p. N749 (Members of order Hippuritoida and superfamily Hippuritacea collectively are designated commonly as rudists) p. 766 (The hypothesis is here accepted that the rudists were derived from the Megalodontidae, and they are considered to form a major taxon of the Bivalvia to which Steinman assigned the name Pachyodonta, and for which the name Hippuritoida is adopted in this treatise.)

found: Web. 3(Rudista: in some classifications, a division of Eulamellibranchia comprising extinct chiefly Cretaceous bivalve mollusks with one valve elongate, conical, and thick-shelled and the other small and fitting like a lid on the first; n. rudistid; syn. Rudistae)