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Primulaceae

Phylogenetic investigation based on DNA sequences and morphology has shown the Primulaceae, as traditionally defined, to be polyphyletic (Källersjö et al. 2000). In order that the taxonomic names refect the evolutionary history of this group, some genera (specifically the terrestrial, non-basal-rosette species) have been moved to other families ( Anagallis, Centunculus, Lysimachia, and Trientalis to the Myrsinaceae and Samolus to the Theophrastaceae).

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Hottonia
1a. Plants aquatic; leaf blades narrowly dissected [Fig. 806]; peduncles and axes of the terminal racemes conspicuously inflated, the flowers whorled at the constricted nodes [Fig. 806]
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1b. Plants terrestrial; leaf blades simple; peduncles and axes of inflorescence not or scarcely inflated, the flowers in a solitary, terminal umbel or in racemes with whorls of flowers
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  Androsace
  2a. Corolla white, the basal, connate portion of the corolla ± equal in lenth to the calyx, constricted at the opening; style very short; plants annual
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  Primula
  2b. Corolla pink to purple, red, yellow, or rarely white, the basal, connate portion of the corolla longer than the calyx (+/- equal to the calyx in the yellow-flowered P. veris), not or scarcely constricted at opening; style elongate; plants perennial

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Show photos of: Each photo represents one genus in this family.