endressii) are known as spikes of bisexual flowers with the
androecium attached to the back of a carpel, but the New Jersey species (C.
B--Lateral view with one petal removed, showing the gynoecium and the
androecium. C--Bottom-up view of the flowers, showing the stigmas in the center of each flower surrounded by anthers with large purple connectives.
11 cm diam., assimetric; sepals green to green-vinaceous, deltoid to ovate or ovate to elliptic, abaxial surface glabrous, 18-36 X 7-18 mm; petals golden yellow, two external, ovate, 14-36 X 7-21 mm, two internal, orbicular, 12-31 X 8-22 mm, cuculus obovate to elliptic, bent around the
androecium, 12-27 X 07-13 mm; stamens light yellow, 6-24 mm long; staminoids 3-5 mm long; ovary light green, pubescent, 16-33 mm long; style light green, 2-5 mm long.
Staminate flowers 2.5-2.6 mm diam., in small, short-stalked, axillary panicles 10-18 mm long; pedicel slender, 2.5-3 mm long, glabrous; sepals very reduced; hypanthium patelliform, 1.5 mm diam., with an inner ring of nectarigenous trichomes between the
androecium and the petals; petals greenish white, triangular, 0.75 mm x 0.75 mm;
androecium with one horizontal, circular rimose (syn)anther, 0.75-0.8 mm diam., on a very reduced stalk (almost sessile), and fringed by simple trichomes around the lower side.
In addition, the
androecium is often differentiated into middle length stamens with nutritive anthers (medium), that provide food for pollinators, and long length stamens with pollinating anthers (long), that provide pollen that is deposited on the stigma (Van der Pijl 1954, Faegri and van der Pijl 1966, Proctor and Yeo 1973).
They are the male reproductive parts of the flower and are collectively called the
androecium. The word "
androecium" (an-DREE-seeum) comes from the Latin word andros (man) and the Greek word oikos (house), which literally translates to "house of man."
If so, and if this allocation had a genetic basis, then a negative genetic correlation might exist between allocation to the
androecium and the gynoecium of flowers.
Reduction of the
androecium in Spergularia marina (Caryophyllaceae).
Some common characteristics were also observed among species pollinated by bat like nocturnal white flowers and
androecium with anthers positioned in a single direction of the flower, which allows the access of bats to flowers, increasing the pollination efficiency.
Among the most important characters for distinguishing the genus is the presence of a zygomorphic
androecium with three abaxial stamens; presence of convex, claviform to pyramidal extrafloral nectaries and cylindrical or plane-compressed fruit with inert dehiscence.