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• Eriocaulaceae
• Eriocaulon
• Eriocaulon aquaticum

Eriocaulon aquaticum — seven-angled pipewort

Facts

Seven-angled pipewort is found in wet soil or shallow water of lakes and slow-moving rivers in all New England states. While many other aquatic plants are wind- or water-pollinated, seven-angled pipewort has a nectar gland near the tip of each petal, to attract insect pollinators.

Habitat

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

Characteristics

• Clonal plantlets

  Turion length

  0 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

  0 mm

  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 length

  4–6 mm

  Inflorescence type

  • the inflorescence is a pseudanthium (a cluster of small flowers that appear to be one flower (e.g., flower head of composites)
  • the inflorescence is a spike (a long unbranched stem with flowers along it that lack stalks)

  Inflorescence width

  4–10 mm

  Length of flower stalk

  0 mm

  Length of peduncle

  30–200 mm

  Nectar spur

  the flower has no nectar spurs

  Number of carpels

  0–2

  Ovary position

  the sepals and/or petals are attached below the ovary

  Palate on corolla

  no

  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

  • other
  • white

  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 hairs on the inner/upper petal surface

  Petal length

  0.5–1.5 mm

  Petal number

  2

  Petal or sepal number

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

  Pistil number

  • 0
  • 1

  Sepal appearance

  the sepals resemble leaves in color and texture

  Sepal length

  1.5 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

  0 mm

  Stamen number

  • 0
  • 4

  Stamen position relative to petals

  NA

  Stamens fused to petals

  the stamens are not fused to the petals or tepals

  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

  Root septa

  the roots 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

  there are only slender roots on the plant

• 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

  NA

  Floating leaf blade width

  0 mm

  Floating leaf length

  0 mm

  Floating leaf shape

  NA

  Floating leaf tip

  NA

  Floral bract form

  the bracts are roughly as lobed as the foliage leaves

  Floral bract length

  1–1.5 mm

  Leaf arrangement

  basal: the leaves are growing only at the base of the plant

  Leaf blade length

  10–400 mm

  Leaf blade veins

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

  Leaf blade width

  2–5 mm

  Leaf position

  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 air passage number

  At least 1440

  Underwater leaf air passage relative width

  At least 1442

  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)
  • the underwater leaf blade is subulate (awl-shaped; narrowly tapering from the base to the tip)

  Underwater leaf blade veins

  3–9

  Underwater leaf blade width

  2–5 mm

  Underwater leaf length

  10–400 mm

  Underwater leaf stalk

  no

  Underwater leaf stalk length

  0 mm

  Underwater leaf tip shape

  the tip of the underwater leaf is acuminate (tapers to a long, thin point)

  Veins in floating leaf

  0

• Place

  Habitat

  • aquatic
  • wetlands

  New England state

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

  Specific habitat

  • in lakes or ponds
  • in rivers or streams
  • shores of rivers or lakes

• 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