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• Aquatic plants
• Water plants with leaves and stems
• Sagittaria filiformis

Sagittaria filiformis — narrow-leaved arrowhead

Facts

Narrow-leaved arrowhead is found in slow to moderately-moving water of rivers, and its morphology can be quite plastic depending on water depth. Only tall plants growing in deep water produce flowers and fruits.

Habitat

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

  Carpels fused

  the carpel is solitary or (if 2 or more) the carpels are not fused to one another

  Flower lower lip length

  0 mm

  Flower position

  • the flowers are above the surface of the water
  • the flowers are below the surface of the water
  • the flowers are floating on 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

  150–250 mm

  Inflorescence type

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

  Inflorescence width

  50–150 mm

  Length of flower stalk

  15–45 mm

  Length of peduncle

  100–2000 mm

  Nectar spur

  the flower has no nectar spurs

  Number of carpels

  At least 3

  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

  white

  Petal fringed edges

  the petals are not fringed

  Petal fusion

  the perianth parts are separate

  Petal hairs on inner/upper surface

  there are no hairs on the inner/upper petal surface

  Petal number

  3

  Petal or sepal number

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

  Pistil number

  6 or more

  Sepal appearance

  the sepals resemble leaves in color and texture

  Sepal number

  3

  Spur length

  0 mm

  Stamen number

  • 10
  • 11
  • 12
  • 13 or more
  • 7
  • 8
  • 9

  Stamen position relative to petals

  NA

  Stamens fused to petals

  the stamens are not fused to the petals or tepals

• Fruits or seeds

  Fruit beak length

  1 mm

  Fruit length

  5 mm

  Fruit type (general)

  the fruit is dry but does not split open when ripe

  Fruit type (specific)

  the fruit is an achene (dry, usually 1-seeded, does not separate or split open at maturity)

  Fruit width

  2.5 mm

• Glands or sap

  Sap

  the sap is milky and opaque, and may be white or colored

• 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

  the plant has one or more swollen storage organs underground, such as bulbs, tubers or corms

• 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 blade width

  Up to 5 mm

  Floating leaf length

  Up to 400 mm

  Floating leaf shape

  • the leaf blade is linear (very narrow with more or less parallel sides)
  • the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
  • the leaf blade is sagittate (arrow-shaped with backward-facing pointed lobes)

  Floating leaf tip

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

  Floral bract form

  the bracts are roughly as lobed as the foliage leaves

  Floral bract length

  Up to 110 mm

  Leaf arrangement

  the leaves are growing only at the base of the plant (basal)

  Leaf blade length

  300–2500 mm

  Leaf blade veins

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

  Leaf blade width

  1–15 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

  the leaf-like branches are flat

  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

  1–15 mm

  Underwater leaf length

  300–2500 mm

  Underwater leaf stalk

  no

  Underwater leaf stalk length

  0 mm

  Underwater leaf tip shape

  • the tip of the underwater leaf is acute (sharply pointed)
  • the tip of the underwater leaf is rounded, with no point

  Veins in floating leaf

  anything

• Place

  Habitat

  • aquatic
  • wetlands

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • Rhode Island

  Specific habitat

  in rivers or streams

• Stem, shoot, branch

  Flowering stem growth form

  • the flowering stem is upright
  • 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