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• Pontederiaceae
• Heteranthera
• Heteranthera dubia

Heteranthera dubia — grass-leaved mud-plantain

Facts

Grass-leaved mud-plantain is found in neutral or basic, slow-moving water of lakes and rivers. The shape of the leaf blades is variable, being somewhat shorter and wider if the plant is subjected to a current, longer and narrower in plants growing in ponds or lakes.

Habitat

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

Characteristics

• Clonal plantlets

  Turion length

  0 mm

• Flowers

  Anther color

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

  Anther length

  4 mm

  Carpels fused

  the carpels are fused to one another

  Flower lower lip length

  0 mm

  Flower number

  1

  Flower position

  the flowers are above the surface of the water

  Flower symmetry

  there are two or more ways to evenly divide the flower (the flower is radially symmetrical)

  Inflorescence type

  the inflorescence has only one flower on it

  Length of flower stalk

  0 mm

  Length of peduncle

  0 mm

  Nectar spur

  the flower has no nectar spurs

  Number of carpels

  3

  Ovary position

  the sepals and/or petals are attached below the ovary

  Palate on corolla

  no

  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
  • the perianth parts are separate

  Petal hairs on inner/upper surface

  there are no hairs on the inner/upper petal surface

  Petal length

  4–11 mm

  Petal number

  3

  Petal or sepal number

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

  Pistil number

  1

  Sepal appearance

  the sepals resemble petals in color and texture

  Sepal length

  4–11 mm

  Sepal number

  3

  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

  0 mm

  Stamen length

  2–10 mm

  Stamen number

  3

  Stamen position relative to petals

  NA

  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 number

  1

• Fruits or seeds

  Fruit length

  10 mm

  Fruit type (general)

  the fruit is dry but does not split 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

  Root septa

  the roots do not have transverse septa

  Roots floating in water

  there are no clusters of roots floating in the water

  Turions

  there are no turions on the plant

  Underground organs

  • the plant has a rhizome (a horizontal underground stem with roots growing from it)
  • there are only slender roots on the plant

• Leaves

  Bract position (Sparganium)

  NA

  Floating leaf basal lobes

  NA

  Floating leaf blade width

  1–3 mm

  Floating leaf length

  20–40 mm

  Floating leaf shape

  the leaf blade is linear (very narrow with more or less parallel sides)

  Floating leaf tip

  the tip of the floating leaf blade is obtuse (bluntly pointed)

  Leaf arrangement

  alternate: there is one leaf per node along the stem

  Leaf blade length

  20–100 mm

  Leaf blade veins

  the lateral veins are parallel or slightly arched in the direction of the tip

  Leaf blade width

  1–5 mm

  Leaf position

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

  Leaf special features

  none of the mentioned special features are present

  Leaf-like branch segments

  0

  Leaf-like branch shape

  NA

  Specific leaf type

  the leaf is not divided, rather the blade is made up of one segment

  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

  0 mm

  Underwater leaf blade edges

  the underwater leaf has smooth edges, without teeth

  Underwater leaf blade shape

  the underwater leaf blade is linear (very narrow with more or less parallel sides)

  Underwater leaf blade width

  1–5 mm

  Underwater leaf length

  30–100 mm

  Underwater leaf stalk

  no

  Underwater leaf stalk length

  0 mm

  Underwater leaf tip shape

  the tip of the underwater leaf is obtuse (bluntly pointed)

  Veins in floating leaf

  0

• Place

  Habitat

  aquatic

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • 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