Our understanding of diversification of dicotyledonous angiosperms during the Upper Cretaceous has increased dramatically in light of new evidence from fossilized flowers. These fossil flowers include taxa with affinities to several modern clades. The monocot clade (or Class Liliopsida) includes approximately 50,000 extant species and is widely considered to be an early offshoot from relatively primitive dicotyledons. Based on their putative early divergence, one might expect to find evidence of monocot diversification concurrent with early dicot diversification. In contrast to their modern diversity, the fossil record of monocots is meager and the earliest examples (leaves and pollen) are equivocal. Previously reported Triurid flowers from the Raritan Formation (Upper Cretaceous, ~90 MYBP), New Jersey are the oldest known monocot flowers, and are the least equivocal early monocot organs. Specific variation based on additional collections and more intensive analyses is reported here. The triurid fossil flowers can be separated into four distinctive species. One species has unequal and elongate tepals without recurved tips and stamens with short filaments free one from another. A second species has equal and triangular tepals with recurved and acuminate tips, sessile anthers without connective extensions and a central pistillode. The remaining two species have equal and triangular tepals, but with incurved margins, anthers with connective extensions and no pistillode. Of the latter two species, one has sessile anthers and the other has stamens with short filaments connate at the base. Phylogenetic analyses confirm the affinities of the fossils with modern Triuridaceae. The fossil taxa are nested within a completely achlorophyllous saprophytic clade, within the Triuridaceae, supporting the interpretation that the extinct plants were also saprophytic. If so, this represents the earliest known fossil occurrence of the saprophytic habit in angiosperms.

Key words: angiosperms, cladistics, Cretaceous, fossils, monocots, Triuridaceae