Nonflowers near the base of extant angiosperms? Spatiotemporal arrangement of organs in reproductive units of Hydatellaceae and its bearing on the origin of the flower.

  title={Nonflowers near the base of extant angiosperms? Spatiotemporal arrangement of organs in reproductive units of Hydatellaceae and its bearing on the origin of the flower.},
  author={Paula J. Rudall and Margarita V Remizowa and Gerhard Prenner and Christina J. Prychid and Renee E. Tuckett and Dmitry D. Sokoloff},
  journal={American journal of botany},
  volume={96 1},
Reproductive units (RUs) of Trithuria, the sole genus of the early-divergent angiosperm family Hydatellaceae, are compared with flowers of their close relatives in Cabombaceae (Nymphaeales). Trithuria RUs combine features of flowers and inflorescences. They differ from typical flowers in possessing an "inside-out" morphology, with carpels surrounding stamens; furthermore, carpels develop centrifugally, in contrast to centripetal or simultaneous development in typical flowers. Trithuria RUs… 

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