Zygomorphic Flower

Zygomorphic Flower

 

a flower through which one can pass only one plane of symmetry that will divide it into two parts. (The symmetry is established according to the perianth, without consideration of the location of its internal parts.) Three types of zygomorphic flowers are distinguished: typically zygomorphic (the plane of symmetry passes through the pedicel and axis of the inflorescence—that is, it coincides with the median plane, as in Leguminosae and Labiatae), transversely zygomorphic (the plane of symmetry is perpendicular to the median plane, as in Corydalis and Fumaria), and obliquely zygomorphic (the plane of symmetry lies at an acute angle to the median plane, as in horse chestnut). Zygomorphic flowers appeared as a result of a plant’s adaptation to being pollinated by certain insects which penetrate the flower from only one position and always touch the stamens and the stigma of the pistil in the process.

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The species can easily be recognized in the area by leaves with 4 pairs of lanceolate to elliptical leaflets; petiolar extrafloral nectaries; zygomorphic flowers and dry, plane-compressed, little curved fruits.
Although zygomorphic flowers showed overwhelming dominance inall regions (Fig.
Sesame has zygomorphic flowers with pendulous tubular corolla of 3-4 mm in length and coloring of various shades of purple white.
2008), suggest bat-pollination, although the plants in the complex do not show the typical chiropterophilous floral syndrome with bell-shaped, large zygomorphic flowers, characteristic of the bat-pollinated Werauhia species (Kromer et al.
Flies, for instance, won't often visit zygomorphic flowers.
Three of the samples--Paulownia (Bignoniaceae or Paulowniaceae), Hebe (Scrophulariaceae or Plantaginaceae), and Eremophila (Myoporaceae or Scrophulariaceae)--are from the Lamiales, and their floral formulae (Table 1) show some diagnostic features of this order, such as two-lipped zygomorphic flowers with two or four stamens (Judd et al.
Floral anatomy and systematics of Alliaceae with particular reference to Gilliesia, a presumed insect mimic with strongly zygomorphic flowers.
The cloning of the CYCLOIDEA (CYC) gene in Antirrhinum majus (Asteridae) has focused the discussion on the evolution of zygomorphic flowers (Luo et al.
Such additional specializations can occur in flowers with free perianth parts, as in the evolution of a hummingbird-pollinated species of Delphinium (Ranunculaceae) from bumblebee-pollinated ancestors with zygomorphic flowers (Guerrant, 1982).