Biology Reference
In-Depth Information
few hummingbird-pollinated species in which the site of nectar production is
unknown (Vogel, 1998c). The remaining families exhibit a variety of nectar-
ies: receptacular, hypanthial, or staminodial. In
Anisophylleaceae
, recep-
tacular nectaries form hemispherical bulges that protrude between the
stamen filaments (i.e., an interstaminal position) and are also connected be-
hind these filaments (Matthews et al., 2001). In
Corynocarpaceae
nectaries
are found on staminodes (Narayana et al., 1986; Matthews & Endress, 2004).
In
Cucurbitaceae
there two nectary types: (i) hypanthial mesenchymatous
nectaries exuding nectar through stomata, typical of most members of sub-
family Cucurbitoideae (Brown, 1938; Vogel, 1990, 1997; Nepi et al., 1996;
Ashworth & Galetto, 1999; Fahn & Shimony, 2001), and (ii) epidermal nectar-
ies in the form of trichomes, located mostly in the corolla, especially in
genera with male flowers with synandria (Vogel, 1981b, 1990, 1997), which
characterize subfamily Zanonioideae and tribes Cyclanthereae and Scycieae
of subfamily Cucurbitoideae (Vogel, 1997). (See “Cucurbitaceae” on page 48
for a detailed discussion.) There is no certainty on the presence of nectaries in
Tetramelaceae
: Davidson (1973) mentioned the presence of nectar, whereas
Matthews and Endress (2004) described no nectaries, indicating that areas on
the ovary roof may function as nectaries; experimental studies are needed to
clarify this matter.
Fagales.
All the families in this order—
Betulaceae
,
Casuarinaceae
,
Faga-
ceae
,
Juglandaceae
,
Myricaceae
,
Nothofagaceae
, and
Ticodendraceae—
lack nectar-secreting structures, being mostly wind-pollinated or secondarily
insect-pollinated (Cronquist, 1981; Judd et al., 2002).
3.8.11
Eurosids II
In the Eurosid II clade, receptacular nectaries are frequent, mainly intrasta-
minal but also extrastaminal; sepal and petal nectaries are uncommon. In
Tapisciaceae
, the genus
Huertea
possesses an intrastaminal receptacular
nectary, whereas
Tapiscia
has no nectaries (Dickinson, 1986a).
Brassicales.
Within the order,
Bataceae
and
Gyrostemonaceae
are nectar-
less and wind-pollinated (George, 2003; Decraene, 2005), and
Setchellantha-
ceae
also lacks nectaries (Tobe et al., 1999). In the remaining families,
nectaries are mainly receptacular but also hypanthial and staminal; sepal
nectaries are rare. In
Akaniaceae
(including Bretschneideraceae),
Bretschneidera
has a hypanthial nectary that extends from the base of the
filaments to the gynoecium (Decraene et al., 2002), but there are no data on
nectaries in
Akania
. The receptacular nectaries in
Brassicaceae
can be annu-
lar and continuous, or fragmented into two, four, or eight nectaries (e.g.,
