Biology Reference
In-Depth Information
Solanales.
Gynoecial nectaries at the ovary base are the most widespread in
this group; only
Byblidaceae
, with pollen flowers and buzz pollination
(Conran & Carolin, 2004), and
Sphenocleaceae
have no nectaries (Erbar,
1995). In
Convolvulaceae
, the nectary is a receptacular intrastaminal annu-
lar structure surrounding the ovary base, either continuous or lobed (Fahn,
1979; Cronquist, 1981; Stucky & Beckmann, 1982; Pinheiro & Schlindwein,
1998; Galetto & Bernardello, 2004). Sometimes, flowers show a nectar
chamber between the nectary and the insertion of the filaments at the corolla,
which prevents free access to the nectar; thus, visitors can only reach nectar
through five small openings between the filament bases (Pinheiro &
Schlindwein, 1998). In
Hydroleaceae
, a gynoecial nectary is developed at
the base of the ovary, which is annular and five-humped (Di Fulvio, 1997;
Erbar et al., 2005). In
Montiniaceae
, the inferior ovaries of female flowers
show a massive nectary at the summit around the style (Decraene et al.,
2000b). Nectar-secreting
Solanaceae
(considered basal) presents an annular
gynoecial nectary at the base of the ovary, which may be either conspicuous
or inconspicuous externally (see “Solanaceae” on page 51 for a detailed dis-
cussion; Bernardello, 1987; Vogel, 1991, 1998b; Cocucci & Galetto, 1992;
Rabinowitch et al., 1993; Mione & Serazo, 1999).
3.8.14
Euasterids II
In the Euasterid II clade, gynoecial nectaries are the most frequent, followed
by petal nectaries. In
Bruniaceae
, gynoecial nectaries occur on the upper
parts of the inferior to semi-inferior ovaries in the form of a flat or elevated
ring and are quite homogeneous within the family (Quint & Classen-
Bockhoff, 2006). According to Cronquist (1981),
Columelliaceae
has no
nectaries; on the other hand,
Desfontainia
has nectar (Chalcoff et al., 2006),
but the place of secretion has not been determined, although the superior
ovary position suggests an annular nectary at its base. In
Escalloniaceae
, a
family with inferior ovaries, nectaries are located at the top of the ovary,
around the style (Bensel & Palser, 1975c; Bernardello et al., 2000). The
same nectary type seems to be valid for
Eremosynaceae
and
Tribelaceae
,
which are closely related to Escalloniaceae. Anatomical investigations did
not show nectaries in
Paracryphiaceae
(Dickinson & Baas, 1977).
Aquifoliales.
In
Aquifoliaceae
, nectar is supposed to be produced by papil-
lose swellings in the petals, either the base or the middle part (Loesener,
1942), but no anatomical or experimental studies were done to confirm this.
In
Cardiopteridaceae
, the so-called disc is mostly absent (Cronquist, 1981),
but sometimes it may be present, either flat or cushion-like (Kårehed, 2001),
and if nectariferous it may represent a receptacular nectary. In
Stemonuraceae
,
