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Callitriche palustris — vernal water-starwort

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Facts

Vernal water-starwort prefers still or slow-moving waters, but it sometimes becomes exposed as water levels decline. Ducks and other waterfowl eat the leaves and fruit. It also provides protective habitat for fish. Water starworts (Callitriche) are remarkable for having flowers able to be pollinated by wind when emergent (anemophily), by water when floating at the surface (epihydrophily), as well as when submerged (hypohydrophily).

Habitat

Lacustrine (in lakes or ponds), shores of rivers or lakes, swamps

New England distribution

Adapted from BONAP data

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North America distribution

Adapted from BONAP data

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Characteristics

Habitat
aquatic
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont
Flower petal color
NA
Leaf type
the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
Leaf arrangement
  • opposite: there are two leaves per node along the stem
  • whorled: there are three or more leaves per node along the stem
Leaf blade edges
the edge of the leaf blade is entire (has no teeth or lobes)
Flower symmetry
NA
Number of sepals, petals or tepals
there are no petals, sepals, or tepals in the flower, or they are not clearly present
Fusion of sepals and petals
NA
Stamen number
  • 1 or 2
  • 3
Fruit type (general)
the fruit is dry but does not split open when ripe
Fruit length
1–1.4 mm
Show all characteristics

  • Clonal plantlets

    Bulbils
    the plant does not appear to have bulbils
    Bulblets replace flowers
    there are no bulblets where the flowers are located

  • Flowers

    Anther spurs
    the anthers do not have spurs on them
    Calyx symmetry
    NA
    Carpels fused
    the carpels are fused to one another
    Cleistogamous flowers
    there are no cleistogamous flowers on the plan
    Corolla palate
    NA
    Corona lobe length
    0 mm
    Epicalyx
    the flower does not have an epicalyx
    Epicalyx number of parts
    0
    Filament surface
    the filament is smooth, with no hairs or scales
    Flower description
    the flower has an inferior ovary, with or without a hypanthium
    Flower petal color
    NA
    Flower reproductive parts
    the flower has either only pollen- or only seed-producing parts
    Flower symmetry
    NA
    Flowers sunken into stem
    no
    Form of style
    • the flower has two or more completely separate styles
    • the style is branched above the base
    Fused stamen clusters
    NA
    Fusion of sepals and petals
    NA
    Horns in hoods (Asclepias)
    NA
    Hypanthium
    the flower does not have a hypanthium
    Inflorescence one-sided
    the flowers are arrayed in a spiral around the inflorescence axis or branches, or occur singly, or in several ranks
    Inner tepals (Rumex)
    NA
    Marks on petals
    NA
    Nectar spur
    • NA
    • the flower has no nectar spurs
    Number of pistils
    1
    Number of sepals, petals or tepals
    there are no petals, sepals, or tepals in the flower, or they are not clearly present
    Number of styles
    1–2
    Ovary position
    the ovary is above the point of petal and/or sepal attachment
    Petal and sepal arrangement
    the flower includes neither petals nor sepals
    Petal and sepal colors
    NA
    Petal appearance
    NA
    Petal folds or pleats
    NA
    Petal hairs (Viola)
    NA
    Petal number
    0
    Petal tips (Cuscuta)
    NA
    Reproductive system
    each flower has only carpels or only stamens, but both types of flower are present on each plant (monoecious)
    Scales inside corolla
    no
    Sepal and petal color
    NA
    Sepal appendages
    the sepals do not have appendages on them
    Sepal appendages (Oenothera)
    NA
    Sepal color
    NA
    Sepal number
    0
    Stamen attachment
    the stamens are not attached to the petals or tepals
    Stamen number
    • 1 or 2
    • 3
    Stamen position relative to petals
    NA
    Staminodes
    there are no staminodes on the flower
    Umbel flower reproductive parts
    NA

  • Fruits or seeds

    Achene relative orientation
    NA
    Achene shape
    NA
    Achene surface (Polygonum)
    NA
    Achene type
    NA
    Berry color
    NA
    Capsule color (Viola)
    NA
    Capsule splitting
    NA
    Fruit (pyxis) dehiscence
    NA
    Fruit features (Brassicaceae)
    NA
    Fruit length
    1–1.4 mm
    Fruit locules
    two
    Fruit type (general)
    the fruit is dry but does not split open when ripe
    Fruit type (specific)
    the fruit is a nut (dry and indehiscent, with a hard wall, usually containing only one seed and usually subtended by an involucre)
    Legumes (Fabaceae)
    NA
    Mericarp length
    0 mm
    Mericarp segment shape (Desmodium)
    NA
    Other markings on berry
    NA
    Ovary stipe
    the ovary or fruit does not have a stipe
    Placenta arrangement
    the plant has axile placentation, in which the ovules are attached where the septa of a compound ovary are united, usually on the central axis, or to the septa themselves
    Rows of seeds in fruit (Brassicaceae)
    NA
    Schizocarpic fruit compression
    NA
    Schizocarpic fruit segments
    0
    Septum in fruit (Brassicaceae)
    NA
    Wings on fruit
    • the fruit does not have wings on it
    • the fruit has one or more wings on it
    prickles on fruits
    the fruits do not have thorn-like defensive structures

  • Glands or sap

    Glands on leaf blade
    the leaf blades do not have glandular dots or scales
    Sap
    the sap is clear and watery
    Sap color
    the sap is clear

  • Growth form

    Growth form
    the plant is an herb (it has self-supporting stems)
    Lifespan
    the plant lives only a single year or less
    Parasitism
    the plant is not parasitic
    Plant color
    the leaves or young stems of the plant are green
    Plants darken when dry
    no
    Spines on plant
    the plant has no spines

  • Leaves

    Bracteole number (Apiaceae)
    0
    Bracts in plantain (Plantago)
    NA
    Final leaf segment length (compound lvs only)
    0 mm
    Final leaf segment length to width ratio (compound lvs only)
    0
    Final leaf segment width (compound lvs only)
    0 mm
    Hairs on underside of leaf
    the underside of the leaf is not hairy, or it has very few hairs
    Hairs on upper side of leaf
    the upper side of the leaf is not hairy, or it has very few hairs
    Leaf arrangement
    • opposite: there are two leaves per node along the stem
    • whorled: there are three or more leaves per node along the stem
    Leaf blade base
    • the leaf has a distinct leaf stalk (petiole)
    • the leaf has no stalk
    Leaf blade base shape
    the base of the leaf blade is cuneate (wedge-shaped, tapers to the base with relatively straight, converging edges), or narrow
    Leaf blade edges
    the edge of the leaf blade is entire (has no teeth or lobes)
    Leaf blade length
    5–15 mm
    Leaf blade shape
    • the leaf blade is linear (very narrow with more or less parallel sides)
    • the leaf blade is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
    • the leaf blade is spatulate (spoon-shaped; narrow near the base, then suddenly widening to a rounded tip)
    Leaf blade surface colors
    the upper side of the leaf blade is relatively uniform in color
    Leaf duration
    the leaves drop off in winter (or they whither but persist on the plant)
    Leaf form
    the leaves are green, with an expanded blade and a leaf-like texture
    Leaf spines
    there are no spines on the leaf edges
    Leaf stalk
    • the leaves have leaf stalks
    • the leaves have no leaf stalks, but attach directly to the stem
    Leaf stalk attachment to leaf
    the petiole attaches at the basal margin of the leaf blade
    Leaf stalk base
    the petiole base is narrow where it attaches to the stem
    Leaf teeth and lobes
    the edge of the leaf blade is entire (has no teeth or lobes)
    Leaf type
    the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
    Leaflet number
    0
    Leaves per node
    there are two leaves per node along the stem
    Pinnately compound leaf type
    NA
    Specific leaf type
    the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
    Stipels
    NA
    Stipule features
    NA
    Stipules
    there are no stipules on the plant

  • Place

    Habitat
    aquatic
    New England state
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Rhode Island
    • Vermont
    Specific habitat
    • in lakes or ponds
    • shores of rivers or lakes
    • swamps

  • Stem, shoot, branch

    Branched tendrils
    NA
    Hair between stem nodes
    the stem has no hairs between the nodes
    Hairs between stem nodes
    the stem has no hairs between the nodes
    Leaves on stem
    there is at least one full leaf above the base of the flowering stem
    Plant height
    10–20 cm
    Stem roughness between nodes
    the stem does not feel rough
    Tendril origin
    NA
    Tendrils
    the plant does not have tendrils

Wetland status

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

In New England

Distribution

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

Conservation status

Exact status definitions can vary from state to state. For details, please check with your state.

Maine
unranked (S-rank: SNR)
Massachusetts
fairly widespread (S-rank: S4)

From Flora Novae Angliae dichotomous key

3.  Callitriche palustris L. N

vernal water-starwort. Callitriche palustris L. var. verna (L.) Fenley ex Jepson; C. verna L. 
• CT, MA, ME, NH, RI, VT. Shallow, still or slow-moving water of rivers, lakes, and pools, 
sometimes becoming amphibious as water level declines and then found on shorelines 
and in wet depressions.

Native to North America?

Yes

Sometimes confused with

Callitriche heterophylla:
fruit about as wide as long, lacking a thin wing, without or with a shallow groove between the two halves (vs. C. palustris, fruit 0.2 mm or more longer than side, the apical portion of each half with a thin wing and an evident groove between the two haves).
Callitriche terrestris:
fruit 0.5-0.7 mm long, without subtending bracteoles, and leaves monomorphic, 2-5 mm long (vs. C. palustris, with fruit 1-1.4 mm long, subtended by 2 whitish bracteoles, and leaves dimorphic, the submersed ones 5-15 mm long).

Synonyms

  • Callitriche palustris L. var. verna (L.) Fenley ex Jepson
  • Callitriche verna L.

Family

Plantaginaceae

Genus

Callitriche