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

Utricularia radiata — floating bladderwort

Facts

The upper leaves of floating bladderwort are inflated and help keep the inflorescence above the water surface. The bladders of bladderwort are not used for floatation but to catch insects for nutrients.

Habitat

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

Characteristics

• 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

  8–10 mm

  Flower number

  1–7

  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 type

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

  Length of flower stalk

  10–20 mm

  Length of peduncle

  30–100 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 two cycles of petal- or sepal-like structures

  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 mm

  Petal number

  2–5

  Petal or sepal number

  • there are five petals, sepals, or tepals in the flower
  • 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

  2.5–3.5 mm

  Sepal number

  2

  Sepals fused only to sepals

  the sepals are separate from one another

  Stamen number

  1 or 2

  Stamen position relative to petals

  the stamens are lined up with the sepals

  Stamens fused

  the stamens are not fused to one another

  Stamens fused to petals

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

  Style length

  At least 0 mm

  Style number

  0–1

• Fruits or seeds

  Fruit type (general)

  the fruit is dry and splits open when ripe

  Fruit type (specific)

  the fruit is a capsule (splits along two or more seams, apical teeth or pores when dry, to release two or more seeds)

• 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
  • the plant lives only a single year or less

  Root septa

  the roots do not have transverse septa

  Roots floating in water

  there are no clusters of roots floating in the water

  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

  no

  Floating leaf length

  20–55 mm

  Floating leaf shape

  the leaf blade is oblanceolate (lance-shaped, but with the widest point above the middle of the leaf blade)

  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

  2–3 mm

  Leaf arrangement

  • alternate: there is one leaf per node along the stem
  • whorled: there are three or more leaves per node along the stem

  Leaf blade length

  10–55 mm

  Leaf blade veins

  the lateral veins radiate from the base and continue to spread away from the centerline of the leaf, or branch off the central vein at intervals

  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
  • the leaves have inflated petioles or blades that help them float

  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, with five or more levels of division

  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

  Underwater leaf air passage number

  At least 1439

  Underwater leaf air passage relative width

  At least 4336

  Underwater leaf air passage row number

  0

  Underwater leaf blade edges

  the underwater leaf has smooth edges, without teeth

  Underwater leaf blade shape

  • NA
  • the underwater leaf blade is ovate (widest below the middle and broadly tapering at both ends)
  • the underwater leaf blade is reniform (kidney-shaped; wider than long)
  • the underwater leaf blade is triangular, with the stalk or attachment point on one of the sides

  Underwater leaf blade veins

  1–3

  Underwater leaf length

  10–40 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

• 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 is upright

Wetland status

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

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae