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Androdecidua
endressii Magallón, Herendeen et Crane
Androdecidua endressii Magallón, Herendeen et Crane
represents an extinct taxon of the Hamamelidaceae from the late Santonian
(Late Cretaceous) Allon locality, central Georgia, USA. ). Specimens
of A. endressii comprise the androecium and corolla of a whorled,
pentamerous, and actinomorphic flower. The presence of a long apical
extension of the connective and the valvate anther dehiscence indicate
the affinity of A. endressii with the genera of subtribe Loropetalinae
(Hamamelideae; Hamamelidaceae) (Magallón et al., 2002).
Androdecidua endressii Magallón, Herendeen
et Crane. Top view of androecium, with an outer (O) and an inner (I)
whorl of stamens. Scale = 100 m. Modified from Magallón et al.,
2002.
Pollen grains of Androdecidua endressii Magallón,
Herendeen et Crane showing apertures and exine reticulum. Scale = 5
m. Modified from Magallón et al., 2002.

Reconstruction of androecium and corolla of Androdecidua
endressii Magallón, Herendeen et Crane showing lateral
view of androecium and petals. The petals are opposite stamens of
the inner androecial whorl. Modified from Magallón et al.,
2002.

Reconstruction of androecium and corolla of Androdecidua
endressii Magallón, Herendeen et Crane showing staminal
whorls and petals. Stamens are represented only by anthers; the connective
extensions are not shown. Anthers of the outer whorl are bithecal
but have only two pollen sacs, situated abaxially with respect to
the site of attachment of the anther to the filament (dot). The distal
stomial extensions are short. Anthers of the inner whorl are bithecal
and tetrasporangiate. The distal, abaxially directed stomial extensions
are short, but the distal, adaxially directed extensions are longer
and reach the adaxial surface of the anther. Petals are opposite the
inner stamens (Magallón et al., 2002).
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