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Parsimony analyses were conducted for 223 species representing all major groups of angiosperms using entire 18S ribosomal DNA (rDNA) sequences. Although no search swapped to completion, the topologies recovered are highly concordant with those retrieved via broad analyses based on the chloroplast gene rbcL. The general congruence of 18S rDNA and rbcL topologies further clarifies the broad picture of angiosperm phylogeny. In all analyses, the first-branching angiosperms are Amborellaceae, Austrobaileyaceae, Illiciaceae, and Schisandraceae, all woody magnoliids. These taxa are always followed by the paleoherb family Nymphaeaceae. This same general order of early-branching taxa is preserved with several suites of outgroups. In most searches, the remaining early-branching taxa represent Piperales and other orders of subclass Magnoliidae (sensu Cronquist). With the exception of Acorus, the …