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• Aquatic plants
• Water plants with leaves and stems
• Utricularia vulgaris

Utricularia vulgaris — common bladderwort, greater bladderwort

Facts

Like other bladderworts, greater bladderwort is carnivorous, trapping small organisms in its tiny bladders. The trap door operates at speeds that rank among the fastest plant movements known. Triggered by protruding hairs on the door, trap bladders open in about 0.5 milliseconds, sucking the animal in, and closing in about 2.5 milliseconds. This comes to about three thousand feet per second, almost three times the speed of sound. Not bad for a herbaceous plant.

Habitat

Lacustrine (in lakes or ponds), riverine (in rivers or streams)

Characteristics

• Clonal plantlets

  Turion length

  10–20 mm

• Flowers

  Anther color

  there is a noticeable pink, reddish or purplish tint to the anthers

  Carpels fused

  the carpels are fused to one another

  Flower lower lip length

  10–20 mm

  Flower number

  3–14

  Flower position

  the flowers are above the surface of the water

  Flower symmetry

  there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)

  Inflorescence length

  100–300 mm

  Inflorescence type

  the inflorescence is a raceme (a long unbranched stem with stalked flowers growing along it)

  Length of flower stalk

  8–16 mm

  Length of peduncle

  60–200 mm

  Nectar spur

  the flower has nectar spurs

  Number of carpels

  2

  Ovary position

  the sepals and/or petals are attached below the ovary

  Palate on corolla

  yes

  Petal and sepal arrangement

  the flower includes only one cycle of petals or sepals

  Petal appearance

  the petals are thin and delicate, and pigmented (colored other than green or brown)

  Petal color

  yellow

  Petal fringed edges

  the petals are not fringed

  Petal fusion

  the perianth parts are fused to form a tube, cup, or bell shape

  Petal hairs on inner/upper surface

  there are no hairs on the inner/upper petal surface

  Petal length

  15–25 mm

  Petal number

  2

  Petal or sepal number

  there are two petals, sepals, or tepals in the flower

  Pistil number

  1

  Sepal appearance

  the sepals resemble leaves in color and texture

  Sepal length

  2.5–5 mm

  Sepal number

  2

  Sepals fused only to sepals

  • the sepals are fused to each other (not other flower parts), at least near their bases
  • the sepals are separate from one another

  Spur length

  At least 3 mm

  Stamen number

  1 or 2

  Stamen position relative to petals

  NA

  Stamens fused to petals

  the stamens are fused near the bases of the petals or tepals

  Style number

  1

• Fruits or seeds

  Fruit length

  3–5 mm

  Fruit type (general)

  the fruit is dry and splits open when ripe

  Fruit type (specific)

  the fruit is a pyxis (when dry it splits around the middle, and the top falls off, exposing the seeds)

  Fruit width

  5 mm

• Glands or sap

  Oil glands on nodes

  none of the nodes have oil glands

  Sap

  the sap is clear and watery

• Growth form

  Lifespan

  the plant lives more than two years

  Root septa

  NA

  Roots floating in water

  NA

  Turions

  the plant has turions

  Underground organs

  NA

• Leaves

  Bract position (Sparganium)

  NA

  Bract relative length

  At least 1379 mm

  Bracts

  the flowers or their pedicels have bracts at their bases

  Floating leaf basal lobes

  yes

  Floating leaf blade width

  Up to 0.75 mm

  Floating leaf length

  0 mm

  Floating leaf shape

  • the leaf blade is elliptic (widest near the middle and tapering at both ends)
  • the leaf blade is ovate (widest below the middle and broadly tapering at both ends)

  Floating leaf tip

  • the tip of the floating leaf blade is obtuse (bluntly pointed)
  • the tip of the floating leaf blade is rounded, with no point

  Floral bract form

  the bracts are much more lobed, or much less lobed, than the foliage leaves

  Floral bract length

  3–6 mm

  Leaf arrangement

  alternate: there is one leaf per node along the stem

  Leaf blade length

  15–60 mm

  Leaf blade width

  Up to 0.75 mm

  Leaf position

  • some of the leaves are floating at the surface of the water
  • the leaves are all submerged underwater

  Leaf special features

  the leaves have bladder-like traps

  Leaf-like branch segments

  0

  Leaf-like branch shape

  the leaf-like branches are round

  Specific leaf type

  • the leaf is divided into two equal parts which in turn are divided into two further parts; each of these parts are divided and each of these may be further divided
  • the leaf is divided into two equal parts; these parts may also be divided into two further parts
  • the leaf is pinnately compound (i.e., it has three or leaflets distributed along a central axis

  Staminate bract edge (Myriophyllum)

  NA

  Stipule appearance

  NA

  Stipule fused to leaf

  NA

  Stipules

  there are no stipules on the plant

  Stipules fused around stem

  NA

  Trap-bladder length

  1.5–5 mm

  Underwater leaf blade edges

  • the underwater leaf blades are lobed
  • the underwater leaf has tiny, one-celled spines or points along the edge

  Underwater leaf blade shape

  • NA
  • the underwater leaf blade is elliptic (widest near the middle and tapering at both ends)
  • the underwater leaf blade is ovate (widest below the middle and broadly tapering at both ends)

  Underwater leaf blade width

  Up to 0.75 mm

  Underwater leaf length

  15–60 mm

  Underwater leaf stalk

  yes

  Underwater leaf tip shape

  • the tip of the underwater leaf is obtuse (bluntly pointed)
  • the tip of the underwater leaf is rounded, with no point

  Veins in floating leaf

  0

• Place

  Habitat

  aquatic

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont

  Specific habitat

  • in lakes or ponds
  • in rivers or streams

• Stem, shoot, branch

  Flowering stem growth form

  the flowering stem trails along the substrate, or floats in the water

Wetland status

Occurs only in wetlands. (Wetland indicator code: OBL)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae