- Plants are terrestrial or aquatic herbaceous (not woody) plants with mechanisms for entraping insects.
- Flowers perfect (bisexual), irregular in symmetry.
- Corolla (united-petals) deeply 2-lipped, and spurred at base.
- Calyx (united sepals) 2-5 lobed.
- Pistils (female parts) single, ovary superior (above recepticle), 1-cavitied, 2-lobed.
- Fruit a capsule 2-valved or opening irregularily.
- Seeds wrinkled, numerous.
- Lentibulariaceae (Butterwort Family) is one of 2 insectivorus (insect eating) plant families in Yukon.
The other being Droseraceae (Sundew Family).
Illustrated Key To Family
Note: Move cursor over image for note on what to look for. Click on image to enlarge.
Dicotomous Key To Family
- A: Plants terrestrial (on land); leaves in a basal rosette, entire, flowers purplish: Pinguicula (Butterworts)
- A: Plants aquatic (in water); leaves alternate, finely divided; flowers yellow:
- C: Bladders and leaves born on separate branches: Utricularia intermedia (Flat-leaved Bladderwort)
- C: Bladders and leaves born on same branches:
- D: Delicate plants with stems less than 0.5mm thick; leaf segments flat; bladders up to 2mm long: Utricularia minor (Lesser Bladderwort)
- D: Coarse plants with stems more than 0.5mm thick;leaf segments round; bladders 3-5mm long: Utricularia vulgaris (Common Bladderwort)
- Dwarf, terrestrial, perennial, herbaceous (not woody) plants.
- Flowers purple, solitary at end of scapes (stalk), scapes one to several.
- Leaves form a basal rosette, margins entire and rolled upward, elliptic-spatulate in shape, yellowish green, succulent, and glandular-viscid on upper surface.
- Leaves trap and then digest insects in the mucilaginous secretions on the upper surface of the leaf.
They have stalked glands with a sticky secretion to trap and hold the prey.
Then there are glands on the suface of the leaf which are dry until the presence of prey when they then release digestive secretions and then absorb the resulting nutrient rich fluid.
- The leaves are also capable of digesting seeds, pollen and other small organisms.
They can digest an insect in about 2 days.
There can often be numerous insects in various stagest of digestion stuck on a single leaf.
Almost 500 flies have been found on one large specimen near Churchill MB.
Central Yukon= 2
- Nonrooting, aquatic, perennial, herbaceous (not woody) plants.
- Leaves alternate, submerged, finely divided, pale green.
- Flowers, yellow, single to several flowered racemes raised above water on naked scapes.
- Plants often reproduce by means of turions (fleshy buds) or winter buds.
- Turions or winter buds, which form at the tip of branches, drop off in autumn when the branch dies and fall to the bottom where they will sprout new plants the following spring.
- Bladders act as both floats and insect traps.
- Bladders are born on the branches will act as floats by filling with gas when the plant is ready to flower.
Once bouyant the plant foats up from the bottom to the surface where its flowering stalk can rise out of the water.
- Bladders can retain enough water to keep the plant alive for a long period if the pond dries up.
- Bladders have appendages on the sides at their enterance. These appendages are triggered by prey swimming past. They cause the enterance to open sucking in water and the prey with it. Once prey are inside the entereance closes and digestive enzymes are released into the bladder.
- Different species of Utricularia (Bladderworts) have different sizes of bladders. Some are so small they catch tiny microscopic organisms. Others large enough to catch misquito larvae and even small fish fry. Large prey like these get stuck in the enterance and are digested in stages.
Central Yukon= 3