
TRAP TYPE: Flypaper Trap
There are currently Ca. 80 listed species of Pinguicula (click
here).
1. Here we see a butterwort, Pinguicula lutea, in its native
habitat near Jacksonville, Florida. Pinguicula lutea occurs
in sunny, open, wet areas throughout the southeastern U.S. Although
butterworts have leaves and therefore trapping mechanisms that look
nothing like those of the bladderworts (Utricularia), the two
belong to the same family (Lentibulariaceae). Pinguicula bears
one or two flowers at the end of a long stalk.
2. The leaves of Pinguicular lutea, seen up close, bear short
hairs, (seen at the base of the lower leaf) which secrete sticky mucilage.
Invisible in the shiny surface of the picture are tiny round glad hairs
that digest insects that are caught in the mucilage.
3. The leaves of Pinguicula are yellowish in color, which
is probably the source of the common name butterwort. The trapping mechanism
of Pinguicula is a simple one. Insects become stuck in the
sticky mucilage (which they may mistake for water or nectar). When an
insect becomes stuck on the mucilage, the edge of the leaf slowly rolls
over. The leaves never completely close. When the insect is digested,
the leaf edges unroll and the leaf becomes more nearly flat.
4. The flowers of Pinguicula lutea are bright yellow. This color is
attractive to bees. A bee could fit easily into the wider part of the
flower of Pinguicula lutea. There is a small pointed tip on
the flower, the spur (at left), which contains a droplet of nectar.
A bee, properly oriented within the flower, could feed on the nectar
if it has a long tongue.
5. Here are the leaves of Pinguicula caerulea, seen from the
above. The bases of three flower stalks can be seen. Pinguicula
caerulea occurs in the southeastern United States.
6. The flowers of Pinguicula caerulea are bluish-purple (the
word caerulea means "sky-blue" in Latin). Here one flower is
seen from the front, one from the side. Notice the small spur on the
flower seen in side view. As with Pinguicula lutea, the flowers of Pinguicula
caerulea are wide enough to admit a bee, and a long-tongued bee
can, when it fully enters the flower, suck nectar from the spur.
The flower of Pinguicula caerulea, seen from the front, features
deep blue-purple veins on a white background. Patterns like this tend
to be associated with be pollination. Where they are, such patterns
are called guidelines, because bees are programmed to follow the direction
of the veins, which lead them into a flower.